update code.

VocieProcess/CMakeLists.txt

@@ -26,11 +26,22 @@ add_library(VocieProcess
     api/units/timestamp.h api/units/timestamp.cc
 
     common_audio/channel_buffer.h common_audio/channel_buffer.cc
+    common_audio/ring_buffer.h common_audio/ring_buffer.c
 
     common_audio/resampler/push_sinc_resampler.h common_audio/resampler/push_sinc_resampler.cc
     common_audio/resampler/sinc_resampler.h common_audio/resampler/sinc_resampler.cc
 
+    common_audio/signal_processing/complex_bit_reverse.c
+    common_audio/signal_processing/complex_fft.c
+    common_audio/signal_processing/cross_correlation.c
+    common_audio/signal_processing/division_operations.c
     common_audio/signal_processing/dot_product_with_scale.h common_audio/signal_processing/dot_product_with_scale.cc
+    common_audio/signal_processing/downsample_fast.c
+    common_audio/signal_processing/min_max_operations.c
+    common_audio/signal_processing/randomization_functions.c
+    common_audio/signal_processing/real_fft.c
+    common_audio/signal_processing/spl_init.c
+    common_audio/signal_processing/vector_scaling_operations.c
 
     common_audio/third_party/ooura/fft_size_128/ooura_fft.h common_audio/third_party/ooura/fft_size_128/ooura_fft.cc
     common_audio/third_party/spl_sqrt_floor/spl_sqrt_floor.h common_audio/third_party/spl_sqrt_floor/spl_sqrt_floor.c
@@ -117,9 +128,14 @@ add_library(VocieProcess
     modules/audio_processing/aec3/suppression_gain.h modules/audio_processing/aec3/suppression_gain.cc
     modules/audio_processing/aec3/transparent_mode.h modules/audio_processing/aec3/transparent_mode.cc
 
+    modules/audio_processing/aecm/aecm_core.h modules/audio_processing/aecm/aecm_core.cc modules/audio_processing/aecm/aecm_core_c.cc
+    modules/audio_processing/aecm/echo_control_mobile.h  modules/audio_processing/aecm/echo_control_mobile.cc
+
     modules/audio_processing/logging/apm_data_dumper.h modules/audio_processing/logging/apm_data_dumper.cc
 
     modules/audio_processing/utility/cascaded_biquad_filter.h modules/audio_processing/utility/cascaded_biquad_filter.cc
+    modules/audio_processing/utility/delay_estimator_wrapper.h  modules/audio_processing/utility/delay_estimator_wrapper.cc
+    modules/audio_processing/utility/delay_estimator.h modules/audio_processing/utility/delay_estimator.cc
 )
 
 target_compile_definitions(VocieProcess
@@ -133,6 +149,7 @@ target_compile_definitions(VocieProcess
 
 target_include_directories(VocieProcess
     PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}
+    INTERFACE ${CMAKE_CURRENT_SOURCE_DIR}
 )
 
 target_link_libraries(VocieProcess

VocieProcess/common_audio/ring_buffer.c

@@ -0,0 +1,232 @@
+/*
+ *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+// A ring buffer to hold arbitrary data. Provides no thread safety. Unless
+// otherwise specified, functions return 0 on success and -1 on error.
+
+#include "common_audio/ring_buffer.h"
+
+#include <stddef.h>  // size_t
+#include <stdlib.h>
+#include <string.h>
+
+// Get address of region(s) from which we can read data.
+// If the region is contiguous, `data_ptr_bytes_2` will be zero.
+// If non-contiguous, `data_ptr_bytes_2` will be the size in bytes of the second
+// region. Returns room available to be read or `element_count`, whichever is
+// smaller.
+static size_t GetBufferReadRegions(RingBuffer* buf,
+                                   size_t element_count,
+                                   void** data_ptr_1,
+                                   size_t* data_ptr_bytes_1,
+                                   void** data_ptr_2,
+                                   size_t* data_ptr_bytes_2) {
+
+  const size_t readable_elements = WebRtc_available_read(buf);
+  const size_t read_elements = (readable_elements < element_count ?
+      readable_elements : element_count);
+  const size_t margin = buf->element_count - buf->read_pos;
+
+  // Check to see if read is not contiguous.
+  if (read_elements > margin) {
+    // Write data in two blocks that wrap the buffer.
+    *data_ptr_1 = buf->data + buf->read_pos * buf->element_size;
+    *data_ptr_bytes_1 = margin * buf->element_size;
+    *data_ptr_2 = buf->data;
+    *data_ptr_bytes_2 = (read_elements - margin) * buf->element_size;
+  } else {
+    *data_ptr_1 = buf->data + buf->read_pos * buf->element_size;
+    *data_ptr_bytes_1 = read_elements * buf->element_size;
+    *data_ptr_2 = NULL;
+    *data_ptr_bytes_2 = 0;
+  }
+
+  return read_elements;
+}
+
+RingBuffer* WebRtc_CreateBuffer(size_t element_count, size_t element_size) {
+  RingBuffer* self = NULL;
+  if (element_count == 0 || element_size == 0) {
+    return NULL;
+  }
+
+  self = malloc(sizeof(RingBuffer));
+  if (!self) {
+    return NULL;
+  }
+
+  self->data = malloc(element_count * element_size);
+  if (!self->data) {
+    free(self);
+    self = NULL;
+    return NULL;
+  }
+
+  self->element_count = element_count;
+  self->element_size = element_size;
+  WebRtc_InitBuffer(self);
+
+  return self;
+}
+
+void WebRtc_InitBuffer(RingBuffer* self) {
+  self->read_pos = 0;
+  self->write_pos = 0;
+  self->rw_wrap = SAME_WRAP;
+
+  // Initialize buffer to zeros
+  memset(self->data, 0, self->element_count * self->element_size);
+}
+
+void WebRtc_FreeBuffer(void* handle) {
+  RingBuffer* self = (RingBuffer*)handle;
+  if (!self) {
+    return;
+  }
+
+  free(self->data);
+  free(self);
+}
+
+size_t WebRtc_ReadBuffer(RingBuffer* self,
+                         void** data_ptr,
+                         void* data,
+                         size_t element_count) {
+
+  if (self == NULL) {
+    return 0;
+  }
+  if (data == NULL) {
+    return 0;
+  }
+
+  {
+    void* buf_ptr_1 = NULL;
+    void* buf_ptr_2 = NULL;
+    size_t buf_ptr_bytes_1 = 0;
+    size_t buf_ptr_bytes_2 = 0;
+    const size_t read_count = GetBufferReadRegions(self,
+                                                   element_count,
+                                                   &buf_ptr_1,
+                                                   &buf_ptr_bytes_1,
+                                                   &buf_ptr_2,
+                                                   &buf_ptr_bytes_2);
+    if (buf_ptr_bytes_2 > 0) {
+      // We have a wrap around when reading the buffer. Copy the buffer data to
+      // `data` and point to it.
+      memcpy(data, buf_ptr_1, buf_ptr_bytes_1);
+      memcpy(((char*) data) + buf_ptr_bytes_1, buf_ptr_2, buf_ptr_bytes_2);
+      buf_ptr_1 = data;
+    } else if (!data_ptr) {
+      // No wrap, but a memcpy was requested.
+      memcpy(data, buf_ptr_1, buf_ptr_bytes_1);
+    }
+    if (data_ptr) {
+      // `buf_ptr_1` == `data` in the case of a wrap.
+      *data_ptr = read_count == 0 ? NULL : buf_ptr_1;
+    }
+
+    // Update read position
+    WebRtc_MoveReadPtr(self, (int) read_count);
+
+    return read_count;
+  }
+}
+
+size_t WebRtc_WriteBuffer(RingBuffer* self,
+                          const void* data,
+                          size_t element_count) {
+  if (!self) {
+    return 0;
+  }
+  if (!data) {
+    return 0;
+  }
+
+  {
+    const size_t free_elements = WebRtc_available_write(self);
+    const size_t write_elements = (free_elements < element_count ? free_elements
+        : element_count);
+    size_t n = write_elements;
+    const size_t margin = self->element_count - self->write_pos;
+
+    if (write_elements > margin) {
+      // Buffer wrap around when writing.
+      memcpy(self->data + self->write_pos * self->element_size,
+             data, margin * self->element_size);
+      self->write_pos = 0;
+      n -= margin;
+      self->rw_wrap = DIFF_WRAP;
+    }
+    memcpy(self->data + self->write_pos * self->element_size,
+           ((const char*) data) + ((write_elements - n) * self->element_size),
+           n * self->element_size);
+    self->write_pos += n;
+
+    return write_elements;
+  }
+}
+
+int WebRtc_MoveReadPtr(RingBuffer* self, int element_count) {
+  if (!self) {
+    return 0;
+  }
+
+  {
+    // We need to be able to take care of negative changes, hence use "int"
+    // instead of "size_t".
+    const int free_elements = (int) WebRtc_available_write(self);
+    const int readable_elements = (int) WebRtc_available_read(self);
+    int read_pos = (int) self->read_pos;
+
+    if (element_count > readable_elements) {
+      element_count = readable_elements;
+    }
+    if (element_count < -free_elements) {
+      element_count = -free_elements;
+    }
+
+    read_pos += element_count;
+    if (read_pos > (int) self->element_count) {
+      // Buffer wrap around. Restart read position and wrap indicator.
+      read_pos -= (int) self->element_count;
+      self->rw_wrap = SAME_WRAP;
+    }
+    if (read_pos < 0) {
+      // Buffer wrap around. Restart read position and wrap indicator.
+      read_pos += (int) self->element_count;
+      self->rw_wrap = DIFF_WRAP;
+    }
+
+    self->read_pos = (size_t) read_pos;
+
+    return element_count;
+  }
+}
+
+size_t WebRtc_available_read(const RingBuffer* self) {
+  if (!self) {
+    return 0;
+  }
+
+  if (self->rw_wrap == SAME_WRAP) {
+    return self->write_pos - self->read_pos;
+  } else {
+    return self->element_count - self->read_pos + self->write_pos;
+  }
+}
+
+size_t WebRtc_available_write(const RingBuffer* self) {
+  if (!self) {
+    return 0;
+  }
+
+  return self->element_count - WebRtc_available_read(self);
+}

VocieProcess/common_audio/ring_buffer.h

@@ -0,0 +1,79 @@
+/*
+ *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+// A ring buffer to hold arbitrary data. Provides no thread safety. Unless
+// otherwise specified, functions return 0 on success and -1 on error.
+
+#ifndef COMMON_AUDIO_RING_BUFFER_H_
+#define COMMON_AUDIO_RING_BUFFER_H_
+
+// TODO(alessiob): Used by AEC, AECm and AudioRingBuffer. Remove when possible.
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stddef.h>  // size_t
+
+enum Wrap { SAME_WRAP, DIFF_WRAP };
+
+typedef struct RingBuffer {
+  size_t read_pos;
+  size_t write_pos;
+  size_t element_count;
+  size_t element_size;
+  enum Wrap rw_wrap;
+  char* data;
+} RingBuffer;
+
+// Creates and initializes the buffer. Returns null on failure.
+RingBuffer* WebRtc_CreateBuffer(size_t element_count, size_t element_size);
+void WebRtc_InitBuffer(RingBuffer* handle);
+void WebRtc_FreeBuffer(void* handle);
+
+// Reads data from the buffer. Returns the number of elements that were read.
+// The `data_ptr` will point to the address where the read data is located.
+// If no data can be read, `data_ptr` is set to `NULL`. If all data can be read
+// without buffer wrap around then `data_ptr` will point to the location in the
+// buffer. Otherwise, the data will be copied to `data` (memory allocation done
+// by the user) and `data_ptr` points to the address of `data`. `data_ptr` is
+// only guaranteed to be valid until the next call to WebRtc_WriteBuffer().
+//
+// To force a copying to `data`, pass a null `data_ptr`.
+//
+// Returns number of elements read.
+size_t WebRtc_ReadBuffer(RingBuffer* handle,
+                         void** data_ptr,
+                         void* data,
+                         size_t element_count);
+
+// Writes `data` to buffer and returns the number of elements written.
+size_t WebRtc_WriteBuffer(RingBuffer* handle,
+                          const void* data,
+                          size_t element_count);
+
+// Moves the buffer read position and returns the number of elements moved.
+// Positive `element_count` moves the read position towards the write position,
+// that is, flushing the buffer. Negative `element_count` moves the read
+// position away from the the write position, that is, stuffing the buffer.
+// Returns number of elements moved.
+int WebRtc_MoveReadPtr(RingBuffer* handle, int element_count);
+
+// Returns number of available elements to read.
+size_t WebRtc_available_read(const RingBuffer* handle);
+
+// Returns number of available elements for write.
+size_t WebRtc_available_write(const RingBuffer* handle);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif  // COMMON_AUDIO_RING_BUFFER_H_

VocieProcess/common_audio/signal_processing/complex_bit_reverse.c

@@ -0,0 +1,108 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "common_audio/signal_processing/include/signal_processing_library.h"
+
+/* Tables for data buffer indexes that are bit reversed and thus need to be
+ * swapped. Note that, index_7[{0, 2, 4, ...}] are for the left side of the swap
+ * operations, while index_7[{1, 3, 5, ...}] are for the right side of the
+ * operation. Same for index_8.
+ */
+
+/* Indexes for the case of stages == 7. */
+static const int16_t index_7[112] = {
+  1, 64, 2, 32, 3, 96, 4, 16, 5, 80, 6, 48, 7, 112, 9, 72, 10, 40, 11, 104,
+  12, 24, 13, 88, 14, 56, 15, 120, 17, 68, 18, 36, 19, 100, 21, 84, 22, 52,
+  23, 116, 25, 76, 26, 44, 27, 108, 29, 92, 30, 60, 31, 124, 33, 66, 35, 98,
+  37, 82, 38, 50, 39, 114, 41, 74, 43, 106, 45, 90, 46, 58, 47, 122, 49, 70,
+  51, 102, 53, 86, 55, 118, 57, 78, 59, 110, 61, 94, 63, 126, 67, 97, 69,
+  81, 71, 113, 75, 105, 77, 89, 79, 121, 83, 101, 87, 117, 91, 109, 95, 125,
+  103, 115, 111, 123
+};
+
+/* Indexes for the case of stages == 8. */
+static const int16_t index_8[240] = {
+  1, 128, 2, 64, 3, 192, 4, 32, 5, 160, 6, 96, 7, 224, 8, 16, 9, 144, 10, 80,
+  11, 208, 12, 48, 13, 176, 14, 112, 15, 240, 17, 136, 18, 72, 19, 200, 20,
+  40, 21, 168, 22, 104, 23, 232, 25, 152, 26, 88, 27, 216, 28, 56, 29, 184,
+  30, 120, 31, 248, 33, 132, 34, 68, 35, 196, 37, 164, 38, 100, 39, 228, 41,
+  148, 42, 84, 43, 212, 44, 52, 45, 180, 46, 116, 47, 244, 49, 140, 50, 76,
+  51, 204, 53, 172, 54, 108, 55, 236, 57, 156, 58, 92, 59, 220, 61, 188, 62,
+  124, 63, 252, 65, 130, 67, 194, 69, 162, 70, 98, 71, 226, 73, 146, 74, 82,
+  75, 210, 77, 178, 78, 114, 79, 242, 81, 138, 83, 202, 85, 170, 86, 106, 87,
+  234, 89, 154, 91, 218, 93, 186, 94, 122, 95, 250, 97, 134, 99, 198, 101,
+  166, 103, 230, 105, 150, 107, 214, 109, 182, 110, 118, 111, 246, 113, 142,
+  115, 206, 117, 174, 119, 238, 121, 158, 123, 222, 125, 190, 127, 254, 131,
+  193, 133, 161, 135, 225, 137, 145, 139, 209, 141, 177, 143, 241, 147, 201,
+  149, 169, 151, 233, 155, 217, 157, 185, 159, 249, 163, 197, 167, 229, 171,
+  213, 173, 181, 175, 245, 179, 205, 183, 237, 187, 221, 191, 253, 199, 227,
+  203, 211, 207, 243, 215, 235, 223, 251, 239, 247
+};
+
+void WebRtcSpl_ComplexBitReverse(int16_t* __restrict complex_data, int stages) {
+  /* For any specific value of stages, we know exactly the indexes that are
+   * bit reversed. Currently (Feb. 2012) in WebRTC the only possible values of
+   * stages are 7 and 8, so we use tables to save unnecessary iterations and
+   * calculations for these two cases.
+   */
+  if (stages == 7 || stages == 8) {
+    int m = 0;
+    int length = 112;
+    const int16_t* index = index_7;
+
+    if (stages == 8) {
+      length = 240;
+      index = index_8;
+    }
+
+    /* Decimation in time. Swap the elements with bit-reversed indexes. */
+    for (m = 0; m < length; m += 2) {
+      /* We declare a int32_t* type pointer, to load both the 16-bit real
+       * and imaginary elements from complex_data in one instruction, reducing
+       * complexity.
+       */
+      int32_t* complex_data_ptr = (int32_t*)complex_data;
+      int32_t temp = 0;
+
+      temp = complex_data_ptr[index[m]];  /* Real and imaginary */
+      complex_data_ptr[index[m]] = complex_data_ptr[index[m + 1]];
+      complex_data_ptr[index[m + 1]] = temp;
+    }
+  }
+  else {
+    int m = 0, mr = 0, l = 0;
+    int n = 1 << stages;
+    int nn = n - 1;
+
+    /* Decimation in time - re-order data */
+    for (m = 1; m <= nn; ++m) {
+      int32_t* complex_data_ptr = (int32_t*)complex_data;
+      int32_t temp = 0;
+
+      /* Find out indexes that are bit-reversed. */
+      l = n;
+      do {
+        l >>= 1;
+      } while (l > nn - mr);
+      mr = (mr & (l - 1)) + l;
+
+      if (mr <= m) {
+        continue;
+      }
+
+      /* Swap the elements with bit-reversed indexes.
+       * This is similar to the loop in the stages == 7 or 8 cases.
+       */
+      temp = complex_data_ptr[m];  /* Real and imaginary */
+      complex_data_ptr[m] = complex_data_ptr[mr];
+      complex_data_ptr[mr] = temp;
+    }
+  }
+}

VocieProcess/common_audio/signal_processing/complex_fft.c

@@ -0,0 +1,299 @@
+/*
+ *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+
+/*
+ * This file contains the function WebRtcSpl_ComplexFFT().
+ * The description header can be found in signal_processing_library.h
+ *
+ */
+
+#include "common_audio/signal_processing/complex_fft_tables.h"
+#include "common_audio/signal_processing/include/signal_processing_library.h"
+#include "rtc_base/system/arch.h"
+
+#define CFFTSFT 14
+#define CFFTRND 1
+#define CFFTRND2 16384
+
+#define CIFFTSFT 14
+#define CIFFTRND 1
+
+
+int WebRtcSpl_ComplexFFT(int16_t frfi[], int stages, int mode)
+{
+    int i, j, l, k, istep, n, m;
+    int16_t wr, wi;
+    int32_t tr32, ti32, qr32, qi32;
+
+    /* The 1024-value is a constant given from the size of kSinTable1024[],
+     * and should not be changed depending on the input parameter 'stages'
+     */
+    n = 1 << stages;
+    if (n > 1024)
+        return -1;
+
+    l = 1;
+    k = 10 - 1; /* Constant for given kSinTable1024[]. Do not change
+         depending on the input parameter 'stages' */
+
+    if (mode == 0)
+    {
+        // mode==0: Low-complexity and Low-accuracy mode
+        while (l < n)
+        {
+            istep = l << 1;
+
+            for (m = 0; m < l; ++m)
+            {
+                j = m << k;
+
+                /* The 256-value is a constant given as 1/4 of the size of
+                 * kSinTable1024[], and should not be changed depending on the input
+                 * parameter 'stages'. It will result in 0 <= j < N_SINE_WAVE/2
+                 */
+                wr = kSinTable1024[j + 256];
+                wi = -kSinTable1024[j];
+
+                for (i = m; i < n; i += istep)
+                {
+                    j = i + l;
+
+                    tr32 = (wr * frfi[2 * j] - wi * frfi[2 * j + 1]) >> 15;
+
+                    ti32 = (wr * frfi[2 * j + 1] + wi * frfi[2 * j]) >> 15;
+
+                    qr32 = (int32_t)frfi[2 * i];
+                    qi32 = (int32_t)frfi[2 * i + 1];
+                    frfi[2 * j] = (int16_t)((qr32 - tr32) >> 1);
+                    frfi[2 * j + 1] = (int16_t)((qi32 - ti32) >> 1);
+                    frfi[2 * i] = (int16_t)((qr32 + tr32) >> 1);
+                    frfi[2 * i + 1] = (int16_t)((qi32 + ti32) >> 1);
+                }
+            }
+
+            --k;
+            l = istep;
+
+        }
+
+    } else
+    {
+        // mode==1: High-complexity and High-accuracy mode
+        while (l < n)
+        {
+            istep = l << 1;
+
+            for (m = 0; m < l; ++m)
+            {
+                j = m << k;
+
+                /* The 256-value is a constant given as 1/4 of the size of
+                 * kSinTable1024[], and should not be changed depending on the input
+                 * parameter 'stages'. It will result in 0 <= j < N_SINE_WAVE/2
+                 */
+                wr = kSinTable1024[j + 256];
+                wi = -kSinTable1024[j];
+
+#ifdef WEBRTC_ARCH_ARM_V7
+                int32_t wri = 0;
+                __asm __volatile("pkhbt %0, %1, %2, lsl #16" : "=r"(wri) :
+                    "r"((int32_t)wr), "r"((int32_t)wi));
+#endif
+
+                for (i = m; i < n; i += istep)
+                {
+                    j = i + l;
+
+#ifdef WEBRTC_ARCH_ARM_V7
+                    register int32_t frfi_r;
+                    __asm __volatile(
+                        "pkhbt %[frfi_r], %[frfi_even], %[frfi_odd],"
+                        " lsl #16\n\t"
+                        "smlsd %[tr32], %[wri], %[frfi_r], %[cfftrnd]\n\t"
+                        "smladx %[ti32], %[wri], %[frfi_r], %[cfftrnd]\n\t"
+                        :[frfi_r]"=&r"(frfi_r),
+                         [tr32]"=&r"(tr32),
+                         [ti32]"=r"(ti32)
+                        :[frfi_even]"r"((int32_t)frfi[2*j]),
+                         [frfi_odd]"r"((int32_t)frfi[2*j +1]),
+                         [wri]"r"(wri),
+                         [cfftrnd]"r"(CFFTRND));
+#else
+                    tr32 = wr * frfi[2 * j] - wi * frfi[2 * j + 1] + CFFTRND;
+
+                    ti32 = wr * frfi[2 * j + 1] + wi * frfi[2 * j] + CFFTRND;
+#endif
+
+                    tr32 >>= 15 - CFFTSFT;
+                    ti32 >>= 15 - CFFTSFT;
+
+                    qr32 = ((int32_t)frfi[2 * i]) * (1 << CFFTSFT);
+                    qi32 = ((int32_t)frfi[2 * i + 1]) * (1 << CFFTSFT);
+
+                    frfi[2 * j] = (int16_t)(
+                        (qr32 - tr32 + CFFTRND2) >> (1 + CFFTSFT));
+                    frfi[2 * j + 1] = (int16_t)(
+                        (qi32 - ti32 + CFFTRND2) >> (1 + CFFTSFT));
+                    frfi[2 * i] = (int16_t)(
+                        (qr32 + tr32 + CFFTRND2) >> (1 + CFFTSFT));
+                    frfi[2 * i + 1] = (int16_t)(
+                        (qi32 + ti32 + CFFTRND2) >> (1 + CFFTSFT));
+                }
+            }
+
+            --k;
+            l = istep;
+        }
+    }
+    return 0;
+}
+
+int WebRtcSpl_ComplexIFFT(int16_t frfi[], int stages, int mode)
+{
+    size_t i, j, l, istep, n, m;
+    int k, scale, shift;
+    int16_t wr, wi;
+    int32_t tr32, ti32, qr32, qi32;
+    int32_t tmp32, round2;
+
+    /* The 1024-value is a constant given from the size of kSinTable1024[],
+     * and should not be changed depending on the input parameter 'stages'
+     */
+    n = ((size_t)1) << stages;
+    if (n > 1024)
+        return -1;
+
+    scale = 0;
+
+    l = 1;
+    k = 10 - 1; /* Constant for given kSinTable1024[]. Do not change
+         depending on the input parameter 'stages' */
+
+    while (l < n)
+    {
+        // variable scaling, depending upon data
+        shift = 0;
+        round2 = 8192;
+
+        tmp32 = WebRtcSpl_MaxAbsValueW16(frfi, 2 * n);
+        if (tmp32 > 13573)
+        {
+            shift++;
+            scale++;
+            round2 <<= 1;
+        }
+        if (tmp32 > 27146)
+        {
+            shift++;
+            scale++;
+            round2 <<= 1;
+        }
+
+        istep = l << 1;
+
+        if (mode == 0)
+        {
+            // mode==0: Low-complexity and Low-accuracy mode
+            for (m = 0; m < l; ++m)
+            {
+                j = m << k;
+
+                /* The 256-value is a constant given as 1/4 of the size of
+                 * kSinTable1024[], and should not be changed depending on the input
+                 * parameter 'stages'. It will result in 0 <= j < N_SINE_WAVE/2
+                 */
+                wr = kSinTable1024[j + 256];
+                wi = kSinTable1024[j];
+
+                for (i = m; i < n; i += istep)
+                {
+                    j = i + l;
+
+                    tr32 = (wr * frfi[2 * j] - wi * frfi[2 * j + 1]) >> 15;
+
+                    ti32 = (wr * frfi[2 * j + 1] + wi * frfi[2 * j]) >> 15;
+
+                    qr32 = (int32_t)frfi[2 * i];
+                    qi32 = (int32_t)frfi[2 * i + 1];
+                    frfi[2 * j] = (int16_t)((qr32 - tr32) >> shift);
+                    frfi[2 * j + 1] = (int16_t)((qi32 - ti32) >> shift);
+                    frfi[2 * i] = (int16_t)((qr32 + tr32) >> shift);
+                    frfi[2 * i + 1] = (int16_t)((qi32 + ti32) >> shift);
+                }
+            }
+        } else
+        {
+            // mode==1: High-complexity and High-accuracy mode
+
+            for (m = 0; m < l; ++m)
+            {
+                j = m << k;
+
+                /* The 256-value is a constant given as 1/4 of the size of
+                 * kSinTable1024[], and should not be changed depending on the input
+                 * parameter 'stages'. It will result in 0 <= j < N_SINE_WAVE/2
+                 */
+                wr = kSinTable1024[j + 256];
+                wi = kSinTable1024[j];
+
+#ifdef WEBRTC_ARCH_ARM_V7
+                int32_t wri = 0;
+                __asm __volatile("pkhbt %0, %1, %2, lsl #16" : "=r"(wri) :
+                    "r"((int32_t)wr), "r"((int32_t)wi));
+#endif
+
+                for (i = m; i < n; i += istep)
+                {
+                    j = i + l;
+
+#ifdef WEBRTC_ARCH_ARM_V7
+                    register int32_t frfi_r;
+                    __asm __volatile(
+                      "pkhbt %[frfi_r], %[frfi_even], %[frfi_odd], lsl #16\n\t"
+                      "smlsd %[tr32], %[wri], %[frfi_r], %[cifftrnd]\n\t"
+                      "smladx %[ti32], %[wri], %[frfi_r], %[cifftrnd]\n\t"
+                      :[frfi_r]"=&r"(frfi_r),
+                       [tr32]"=&r"(tr32),
+                       [ti32]"=r"(ti32)
+                      :[frfi_even]"r"((int32_t)frfi[2*j]),
+                       [frfi_odd]"r"((int32_t)frfi[2*j +1]),
+                       [wri]"r"(wri),
+                       [cifftrnd]"r"(CIFFTRND)
+                    );
+#else
+
+                    tr32 = wr * frfi[2 * j] - wi * frfi[2 * j + 1] + CIFFTRND;
+
+                    ti32 = wr * frfi[2 * j + 1] + wi * frfi[2 * j] + CIFFTRND;
+#endif
+                    tr32 >>= 15 - CIFFTSFT;
+                    ti32 >>= 15 - CIFFTSFT;
+
+                    qr32 = ((int32_t)frfi[2 * i]) * (1 << CIFFTSFT);
+                    qi32 = ((int32_t)frfi[2 * i + 1]) * (1 << CIFFTSFT);
+
+                    frfi[2 * j] = (int16_t)(
+                        (qr32 - tr32 + round2) >> (shift + CIFFTSFT));
+                    frfi[2 * j + 1] = (int16_t)(
+                        (qi32 - ti32 + round2) >> (shift + CIFFTSFT));
+                    frfi[2 * i] = (int16_t)(
+                        (qr32 + tr32 + round2) >> (shift + CIFFTSFT));
+                    frfi[2 * i + 1] = (int16_t)(
+                        (qi32 + ti32 + round2) >> (shift + CIFFTSFT));
+                }
+            }
+
+        }
+        --k;
+        l = istep;
+    }
+    return scale;
+}

VocieProcess/common_audio/signal_processing/complex_fft_tables.h

@@ -0,0 +1,132 @@
+/*
+ *  Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef COMMON_AUDIO_SIGNAL_PROCESSING_COMPLEX_FFT_TABLES_H_
+#define COMMON_AUDIO_SIGNAL_PROCESSING_COMPLEX_FFT_TABLES_H_
+
+#include <stdint.h>
+
+static const int16_t kSinTable1024[] = {
+    0,      201,    402,    603,    804,    1005,   1206,   1406,   1607,
+    1808,   2009,   2209,   2410,   2610,   2811,   3011,   3211,   3411,
+    3611,   3811,   4011,   4210,   4409,   4608,   4807,   5006,   5205,
+    5403,   5601,   5799,   5997,   6195,   6392,   6589,   6786,   6982,
+    7179,   7375,   7571,   7766,   7961,   8156,   8351,   8545,   8739,
+    8932,   9126,   9319,   9511,   9703,   9895,   10087,  10278,  10469,
+    10659,  10849,  11038,  11227,  11416,  11604,  11792,  11980,  12166,
+    12353,  12539,  12724,  12909,  13094,  13278,  13462,  13645,  13827,
+    14009,  14191,  14372,  14552,  14732,  14911,  15090,  15268,  15446,
+    15623,  15799,  15975,  16150,  16325,  16499,  16672,  16845,  17017,
+    17189,  17360,  17530,  17699,  17868,  18036,  18204,  18371,  18537,
+    18702,  18867,  19031,  19194,  19357,  19519,  19680,  19840,  20000,
+    20159,  20317,  20474,  20631,  20787,  20942,  21096,  21249,  21402,
+    21554,  21705,  21855,  22004,  22153,  22301,  22448,  22594,  22739,
+    22883,  23027,  23169,  23311,  23452,  23592,  23731,  23869,  24006,
+    24143,  24278,  24413,  24546,  24679,  24811,  24942,  25072,  25201,
+    25329,  25456,  25582,  25707,  25831,  25954,  26077,  26198,  26318,
+    26437,  26556,  26673,  26789,  26905,  27019,  27132,  27244,  27355,
+    27466,  27575,  27683,  27790,  27896,  28001,  28105,  28208,  28309,
+    28410,  28510,  28608,  28706,  28802,  28897,  28992,  29085,  29177,
+    29268,  29358,  29446,  29534,  29621,  29706,  29790,  29873,  29955,
+    30036,  30116,  30195,  30272,  30349,  30424,  30498,  30571,  30643,
+    30713,  30783,  30851,  30918,  30984,  31049,  31113,  31175,  31236,
+    31297,  31356,  31413,  31470,  31525,  31580,  31633,  31684,  31735,
+    31785,  31833,  31880,  31926,  31970,  32014,  32056,  32097,  32137,
+    32176,  32213,  32249,  32284,  32318,  32350,  32382,  32412,  32441,
+    32468,  32495,  32520,  32544,  32567,  32588,  32609,  32628,  32646,
+    32662,  32678,  32692,  32705,  32717,  32727,  32736,  32744,  32751,
+    32757,  32761,  32764,  32766,  32767,  32766,  32764,  32761,  32757,
+    32751,  32744,  32736,  32727,  32717,  32705,  32692,  32678,  32662,
+    32646,  32628,  32609,  32588,  32567,  32544,  32520,  32495,  32468,
+    32441,  32412,  32382,  32350,  32318,  32284,  32249,  32213,  32176,
+    32137,  32097,  32056,  32014,  31970,  31926,  31880,  31833,  31785,
+    31735,  31684,  31633,  31580,  31525,  31470,  31413,  31356,  31297,
+    31236,  31175,  31113,  31049,  30984,  30918,  30851,  30783,  30713,
+    30643,  30571,  30498,  30424,  30349,  30272,  30195,  30116,  30036,
+    29955,  29873,  29790,  29706,  29621,  29534,  29446,  29358,  29268,
+    29177,  29085,  28992,  28897,  28802,  28706,  28608,  28510,  28410,
+    28309,  28208,  28105,  28001,  27896,  27790,  27683,  27575,  27466,
+    27355,  27244,  27132,  27019,  26905,  26789,  26673,  26556,  26437,
+    26318,  26198,  26077,  25954,  25831,  25707,  25582,  25456,  25329,
+    25201,  25072,  24942,  24811,  24679,  24546,  24413,  24278,  24143,
+    24006,  23869,  23731,  23592,  23452,  23311,  23169,  23027,  22883,
+    22739,  22594,  22448,  22301,  22153,  22004,  21855,  21705,  21554,
+    21402,  21249,  21096,  20942,  20787,  20631,  20474,  20317,  20159,
+    20000,  19840,  19680,  19519,  19357,  19194,  19031,  18867,  18702,
+    18537,  18371,  18204,  18036,  17868,  17699,  17530,  17360,  17189,
+    17017,  16845,  16672,  16499,  16325,  16150,  15975,  15799,  15623,
+    15446,  15268,  15090,  14911,  14732,  14552,  14372,  14191,  14009,
+    13827,  13645,  13462,  13278,  13094,  12909,  12724,  12539,  12353,
+    12166,  11980,  11792,  11604,  11416,  11227,  11038,  10849,  10659,
+    10469,  10278,  10087,  9895,   9703,   9511,   9319,   9126,   8932,
+    8739,   8545,   8351,   8156,   7961,   7766,   7571,   7375,   7179,
+    6982,   6786,   6589,   6392,   6195,   5997,   5799,   5601,   5403,
+    5205,   5006,   4807,   4608,   4409,   4210,   4011,   3811,   3611,
+    3411,   3211,   3011,   2811,   2610,   2410,   2209,   2009,   1808,
+    1607,   1406,   1206,   1005,   804,    603,    402,    201,    0,
+    -201,   -402,   -603,   -804,   -1005,  -1206,  -1406,  -1607,  -1808,
+    -2009,  -2209,  -2410,  -2610,  -2811,  -3011,  -3211,  -3411,  -3611,
+    -3811,  -4011,  -4210,  -4409,  -4608,  -4807,  -5006,  -5205,  -5403,
+    -5601,  -5799,  -5997,  -6195,  -6392,  -6589,  -6786,  -6982,  -7179,
+    -7375,  -7571,  -7766,  -7961,  -8156,  -8351,  -8545,  -8739,  -8932,
+    -9126,  -9319,  -9511,  -9703,  -9895,  -10087, -10278, -10469, -10659,
+    -10849, -11038, -11227, -11416, -11604, -11792, -11980, -12166, -12353,
+    -12539, -12724, -12909, -13094, -13278, -13462, -13645, -13827, -14009,
+    -14191, -14372, -14552, -14732, -14911, -15090, -15268, -15446, -15623,
+    -15799, -15975, -16150, -16325, -16499, -16672, -16845, -17017, -17189,
+    -17360, -17530, -17699, -17868, -18036, -18204, -18371, -18537, -18702,
+    -18867, -19031, -19194, -19357, -19519, -19680, -19840, -20000, -20159,
+    -20317, -20474, -20631, -20787, -20942, -21096, -21249, -21402, -21554,
+    -21705, -21855, -22004, -22153, -22301, -22448, -22594, -22739, -22883,
+    -23027, -23169, -23311, -23452, -23592, -23731, -23869, -24006, -24143,
+    -24278, -24413, -24546, -24679, -24811, -24942, -25072, -25201, -25329,
+    -25456, -25582, -25707, -25831, -25954, -26077, -26198, -26318, -26437,
+    -26556, -26673, -26789, -26905, -27019, -27132, -27244, -27355, -27466,
+    -27575, -27683, -27790, -27896, -28001, -28105, -28208, -28309, -28410,
+    -28510, -28608, -28706, -28802, -28897, -28992, -29085, -29177, -29268,
+    -29358, -29446, -29534, -29621, -29706, -29790, -29873, -29955, -30036,
+    -30116, -30195, -30272, -30349, -30424, -30498, -30571, -30643, -30713,
+    -30783, -30851, -30918, -30984, -31049, -31113, -31175, -31236, -31297,
+    -31356, -31413, -31470, -31525, -31580, -31633, -31684, -31735, -31785,
+    -31833, -31880, -31926, -31970, -32014, -32056, -32097, -32137, -32176,
+    -32213, -32249, -32284, -32318, -32350, -32382, -32412, -32441, -32468,
+    -32495, -32520, -32544, -32567, -32588, -32609, -32628, -32646, -32662,
+    -32678, -32692, -32705, -32717, -32727, -32736, -32744, -32751, -32757,
+    -32761, -32764, -32766, -32767, -32766, -32764, -32761, -32757, -32751,
+    -32744, -32736, -32727, -32717, -32705, -32692, -32678, -32662, -32646,
+    -32628, -32609, -32588, -32567, -32544, -32520, -32495, -32468, -32441,
+    -32412, -32382, -32350, -32318, -32284, -32249, -32213, -32176, -32137,
+    -32097, -32056, -32014, -31970, -31926, -31880, -31833, -31785, -31735,
+    -31684, -31633, -31580, -31525, -31470, -31413, -31356, -31297, -31236,
+    -31175, -31113, -31049, -30984, -30918, -30851, -30783, -30713, -30643,
+    -30571, -30498, -30424, -30349, -30272, -30195, -30116, -30036, -29955,
+    -29873, -29790, -29706, -29621, -29534, -29446, -29358, -29268, -29177,
+    -29085, -28992, -28897, -28802, -28706, -28608, -28510, -28410, -28309,
+    -28208, -28105, -28001, -27896, -27790, -27683, -27575, -27466, -27355,
+    -27244, -27132, -27019, -26905, -26789, -26673, -26556, -26437, -26318,
+    -26198, -26077, -25954, -25831, -25707, -25582, -25456, -25329, -25201,
+    -25072, -24942, -24811, -24679, -24546, -24413, -24278, -24143, -24006,
+    -23869, -23731, -23592, -23452, -23311, -23169, -23027, -22883, -22739,
+    -22594, -22448, -22301, -22153, -22004, -21855, -21705, -21554, -21402,
+    -21249, -21096, -20942, -20787, -20631, -20474, -20317, -20159, -20000,
+    -19840, -19680, -19519, -19357, -19194, -19031, -18867, -18702, -18537,
+    -18371, -18204, -18036, -17868, -17699, -17530, -17360, -17189, -17017,
+    -16845, -16672, -16499, -16325, -16150, -15975, -15799, -15623, -15446,
+    -15268, -15090, -14911, -14732, -14552, -14372, -14191, -14009, -13827,
+    -13645, -13462, -13278, -13094, -12909, -12724, -12539, -12353, -12166,
+    -11980, -11792, -11604, -11416, -11227, -11038, -10849, -10659, -10469,
+    -10278, -10087, -9895,  -9703,  -9511,  -9319,  -9126,  -8932,  -8739,
+    -8545,  -8351,  -8156,  -7961,  -7766,  -7571,  -7375,  -7179,  -6982,
+    -6786,  -6589,  -6392,  -6195,  -5997,  -5799,  -5601,  -5403,  -5205,
+    -5006,  -4807,  -4608,  -4409,  -4210,  -4011,  -3811,  -3611,  -3411,
+    -3211,  -3011,  -2811,  -2610,  -2410,  -2209,  -2009,  -1808,  -1607,
+    -1406,  -1206,  -1005,  -804,   -603,   -402,   -201};
+
+#endif  // COMMON_AUDIO_SIGNAL_PROCESSING_COMPLEX_FFT_TABLES_H_

VocieProcess/common_audio/signal_processing/cross_correlation.c

@@ -0,0 +1,30 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "common_audio/signal_processing/include/signal_processing_library.h"
+
+/* C version of WebRtcSpl_CrossCorrelation() for generic platforms. */
+void WebRtcSpl_CrossCorrelationC(int32_t* cross_correlation,
+                                 const int16_t* seq1,
+                                 const int16_t* seq2,
+                                 size_t dim_seq,
+                                 size_t dim_cross_correlation,
+                                 int right_shifts,
+                                 int step_seq2) {
+  size_t i = 0, j = 0;
+
+  for (i = 0; i < dim_cross_correlation; i++) {
+    int32_t corr = 0;
+    for (j = 0; j < dim_seq; j++)
+      corr += (seq1[j] * seq2[j]) >> right_shifts;
+    seq2 += step_seq2;
+    *cross_correlation++ = corr;
+  }
+}

VocieProcess/common_audio/signal_processing/division_operations.c

@@ -0,0 +1,140 @@
+/*
+ *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+
+/*
+ * This file contains implementations of the divisions
+ * WebRtcSpl_DivU32U16()
+ * WebRtcSpl_DivW32W16()
+ * WebRtcSpl_DivW32W16ResW16()
+ * WebRtcSpl_DivResultInQ31()
+ * WebRtcSpl_DivW32HiLow()
+ *
+ * The description header can be found in signal_processing_library.h
+ *
+ */
+
+#include "common_audio/signal_processing/include/signal_processing_library.h"
+#include "rtc_base/sanitizer.h"
+
+uint32_t WebRtcSpl_DivU32U16(uint32_t num, uint16_t den)
+{
+    // Guard against division with 0
+    if (den != 0)
+    {
+        return (uint32_t)(num / den);
+    } else
+    {
+        return (uint32_t)0xFFFFFFFF;
+    }
+}
+
+int32_t WebRtcSpl_DivW32W16(int32_t num, int16_t den)
+{
+    // Guard against division with 0
+    if (den != 0)
+    {
+        return (int32_t)(num / den);
+    } else
+    {
+        return (int32_t)0x7FFFFFFF;
+    }
+}
+
+int16_t WebRtcSpl_DivW32W16ResW16(int32_t num, int16_t den)
+{
+    // Guard against division with 0
+    if (den != 0)
+    {
+        return (int16_t)(num / den);
+    } else
+    {
+        return (int16_t)0x7FFF;
+    }
+}
+
+int32_t WebRtcSpl_DivResultInQ31(int32_t num, int32_t den)
+{
+    int32_t L_num = num;
+    int32_t L_den = den;
+    int32_t div = 0;
+    int k = 31;
+    int change_sign = 0;
+
+    if (num == 0)
+        return 0;
+
+    if (num < 0)
+    {
+        change_sign++;
+        L_num = -num;
+    }
+    if (den < 0)
+    {
+        change_sign++;
+        L_den = -den;
+    }
+    while (k--)
+    {
+        div <<= 1;
+        L_num <<= 1;
+        if (L_num >= L_den)
+        {
+            L_num -= L_den;
+            div++;
+        }
+    }
+    if (change_sign == 1)
+    {
+        div = -div;
+    }
+    return div;
+}
+
+int32_t WebRtcSpl_DivW32HiLow(int32_t num, int16_t den_hi, int16_t den_low)
+{
+    int16_t approx, tmp_hi, tmp_low, num_hi, num_low;
+    int32_t tmpW32;
+
+    approx = (int16_t)WebRtcSpl_DivW32W16((int32_t)0x1FFFFFFF, den_hi);
+    // result in Q14 (Note: 3FFFFFFF = 0.5 in Q30)
+
+    // tmpW32 = 1/den = approx * (2.0 - den * approx) (in Q30)
+    tmpW32 = (den_hi * approx << 1) + ((den_low * approx >> 15) << 1);
+    // tmpW32 = den * approx
+
+    // result in Q30 (tmpW32 = 2.0-(den*approx))
+    tmpW32 = (int32_t)((int64_t)0x7fffffffL - tmpW32);
+
+    // Store tmpW32 in hi and low format
+    tmp_hi = (int16_t)(tmpW32 >> 16);
+    tmp_low = (int16_t)((tmpW32 - ((int32_t)tmp_hi << 16)) >> 1);
+
+    // tmpW32 = 1/den in Q29
+    tmpW32 = (tmp_hi * approx + (tmp_low * approx >> 15)) << 1;
+
+    // 1/den in hi and low format
+    tmp_hi = (int16_t)(tmpW32 >> 16);
+    tmp_low = (int16_t)((tmpW32 - ((int32_t)tmp_hi << 16)) >> 1);
+
+    // Store num in hi and low format
+    num_hi = (int16_t)(num >> 16);
+    num_low = (int16_t)((num - ((int32_t)num_hi << 16)) >> 1);
+
+    // num * (1/den) by 32 bit multiplication (result in Q28)
+
+    tmpW32 = num_hi * tmp_hi + (num_hi * tmp_low >> 15) +
+        (num_low * tmp_hi >> 15);
+
+    // Put result in Q31 (convert from Q28)
+    tmpW32 = WEBRTC_SPL_LSHIFT_W32(tmpW32, 3);
+
+    return tmpW32;
+}

VocieProcess/common_audio/signal_processing/downsample_fast.c

@@ -0,0 +1,65 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "common_audio/signal_processing/include/signal_processing_library.h"
+
+#include "rtc_base/checks.h"
+#include "rtc_base/sanitizer.h"
+
+// TODO(Bjornv): Change the function parameter order to WebRTC code style.
+// C version of WebRtcSpl_DownsampleFast() for generic platforms.
+int WebRtcSpl_DownsampleFastC(const int16_t* data_in,
+                              size_t data_in_length,
+                              int16_t* data_out,
+                              size_t data_out_length,
+                              const int16_t* __restrict coefficients,
+                              size_t coefficients_length,
+                              int factor,
+                              size_t delay) {
+  int16_t* const original_data_out = data_out;
+  size_t i = 0;
+  size_t j = 0;
+  int32_t out_s32 = 0;
+  size_t endpos = delay + factor * (data_out_length - 1) + 1;
+
+  // Return error if any of the running conditions doesn't meet.
+  if (data_out_length == 0 || coefficients_length == 0
+                           || data_in_length < endpos) {
+    return -1;
+  }
+
+  rtc_MsanCheckInitialized(coefficients, sizeof(coefficients[0]),
+                           coefficients_length);
+
+  for (i = delay; i < endpos; i += factor) {
+    out_s32 = 2048;  // Round value, 0.5 in Q12.
+
+    for (j = 0; j < coefficients_length; j++) {
+      // Negative overflow is permitted here, because this is
+      // auto-regressive filters, and the state for each batch run is
+      // stored in the "negative" positions of the output vector.
+      rtc_MsanCheckInitialized(&data_in[(ptrdiff_t) i - (ptrdiff_t) j],
+          sizeof(data_in[0]), 1);
+      // out_s32 is in Q12 domain.
+      out_s32 += coefficients[j] * data_in[(ptrdiff_t) i - (ptrdiff_t) j];
+    }
+
+    out_s32 >>= 12;  // Q0.
+
+    // Saturate and store the output.
+    *data_out++ = WebRtcSpl_SatW32ToW16(out_s32);
+  }
+
+  RTC_DCHECK_EQ(original_data_out + data_out_length, data_out);
+  rtc_MsanCheckInitialized(original_data_out, sizeof(original_data_out[0]),
+                           data_out_length);
+
+  return 0;
+}

VocieProcess/common_audio/signal_processing/include/real_fft.h

@@ -0,0 +1,96 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef COMMON_AUDIO_SIGNAL_PROCESSING_INCLUDE_REAL_FFT_H_
+#define COMMON_AUDIO_SIGNAL_PROCESSING_INCLUDE_REAL_FFT_H_
+
+#include <stdint.h>
+
+// For ComplexFFT(), the maximum fft order is 10;
+// WebRTC APM uses orders of only 7 and 8.
+enum { kMaxFFTOrder = 10 };
+
+struct RealFFT;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct RealFFT* WebRtcSpl_CreateRealFFT(int order);
+void WebRtcSpl_FreeRealFFT(struct RealFFT* self);
+
+// Compute an FFT for a real-valued signal of length of 2^order,
+// where 1 < order <= MAX_FFT_ORDER. Transform length is determined by the
+// specification structure, which must be initialized prior to calling the FFT
+// function with WebRtcSpl_CreateRealFFT().
+// The relationship between the input and output sequences can
+// be expressed in terms of the DFT, i.e.:
+//     x[n] = (2^(-scalefactor)/N)  . SUM[k=0,...,N-1] X[k].e^(jnk.2.pi/N)
+//     n=0,1,2,...N-1
+//     N=2^order.
+// The conjugate-symmetric output sequence is represented using a CCS vector,
+// which is of length N+2, and is organized as follows:
+//     Index:      0  1  2  3  4  5   . . .   N-2       N-1       N       N+1
+//     Component:  R0 0  R1 I1 R2 I2  . . .   R[N/2-1]  I[N/2-1]  R[N/2]  0
+// where R[n] and I[n], respectively, denote the real and imaginary components
+// for FFT bin 'n'. Bins  are numbered from 0 to N/2, where N is the FFT length.
+// Bin index 0 corresponds to the DC component, and bin index N/2 corresponds to
+// the foldover frequency.
+//
+// Input Arguments:
+//   self - pointer to preallocated and initialized FFT specification structure.
+//   real_data_in - the input signal. For an ARM Neon platform, it must be
+//                  aligned on a 32-byte boundary.
+//
+// Output Arguments:
+//   complex_data_out - the output complex signal with (2^order + 2) 16-bit
+//                      elements. For an ARM Neon platform, it must be different
+//                      from real_data_in, and aligned on a 32-byte boundary.
+//
+// Return Value:
+//   0  - FFT calculation is successful.
+//   -1 - Error with bad arguments (null pointers).
+int WebRtcSpl_RealForwardFFT(struct RealFFT* self,
+                             const int16_t* real_data_in,
+                             int16_t* complex_data_out);
+
+// Compute the inverse FFT for a conjugate-symmetric input sequence of length of
+// 2^order, where 1 < order <= MAX_FFT_ORDER. Transform length is determined by
+// the specification structure, which must be initialized prior to calling the
+// FFT function with WebRtcSpl_CreateRealFFT().
+// For a transform of length M, the input sequence is represented using a packed
+// CCS vector of length M+2, which is explained in the comments for
+// WebRtcSpl_RealForwardFFTC above.
+//
+// Input Arguments:
+//   self - pointer to preallocated and initialized FFT specification structure.
+//   complex_data_in - the input complex signal with (2^order + 2) 16-bit
+//                     elements. For an ARM Neon platform, it must be aligned on
+//                     a 32-byte boundary.
+//
+// Output Arguments:
+//   real_data_out - the output real signal. For an ARM Neon platform, it must
+//                   be different to complex_data_in, and aligned on a 32-byte
+//                   boundary.
+//
+// Return Value:
+//   0 or a positive number - a value that the elements in the `real_data_out`
+//                            should be shifted left with in order to get
+//                            correct physical values.
+//   -1 - Error with bad arguments (null pointers).
+int WebRtcSpl_RealInverseFFT(struct RealFFT* self,
+                             const int16_t* complex_data_in,
+                             int16_t* real_data_out);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif  // COMMON_AUDIO_SIGNAL_PROCESSING_INCLUDE_REAL_FFT_H_

VocieProcess/common_audio/signal_processing/min_max_operations.c

@@ -0,0 +1,258 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+/*
+ * This file contains the implementation of functions
+ * WebRtcSpl_MaxAbsValueW16C()
+ * WebRtcSpl_MaxAbsValueW32C()
+ * WebRtcSpl_MaxValueW16C()
+ * WebRtcSpl_MaxValueW32C()
+ * WebRtcSpl_MinValueW16C()
+ * WebRtcSpl_MinValueW32C()
+ * WebRtcSpl_MaxAbsIndexW16()
+ * WebRtcSpl_MaxIndexW16()
+ * WebRtcSpl_MaxIndexW32()
+ * WebRtcSpl_MinIndexW16()
+ * WebRtcSpl_MinIndexW32()
+ *
+ */
+
+#include <stdlib.h>
+#include <limits.h>
+
+#include "rtc_base/checks.h"
+#include "common_audio/signal_processing/include/signal_processing_library.h"
+
+// TODO(bjorn/kma): Consolidate function pairs (e.g. combine
+//   WebRtcSpl_MaxAbsValueW16C and WebRtcSpl_MaxAbsIndexW16 into a single one.)
+// TODO(kma): Move the next six functions into min_max_operations_c.c.
+
+// Maximum absolute value of word16 vector. C version for generic platforms.
+int16_t WebRtcSpl_MaxAbsValueW16C(const int16_t* vector, size_t length) {
+  size_t i = 0;
+  int absolute = 0, maximum = 0;
+
+  RTC_DCHECK_GT(length, 0);
+
+  for (i = 0; i < length; i++) {
+    absolute = abs((int)vector[i]);
+
+    if (absolute > maximum) {
+      maximum = absolute;
+    }
+  }
+
+  // Guard the case for abs(-32768).
+  if (maximum > WEBRTC_SPL_WORD16_MAX) {
+    maximum = WEBRTC_SPL_WORD16_MAX;
+  }
+
+  return (int16_t)maximum;
+}
+
+// Maximum absolute value of word32 vector. C version for generic platforms.
+int32_t WebRtcSpl_MaxAbsValueW32C(const int32_t* vector, size_t length) {
+  // Use uint32_t for the local variables, to accommodate the return value
+  // of abs(0x80000000), which is 0x80000000.
+
+  uint32_t absolute = 0, maximum = 0;
+  size_t i = 0;
+
+  RTC_DCHECK_GT(length, 0);
+
+  for (i = 0; i < length; i++) {
+    absolute =
+        (vector[i] != INT_MIN) ? abs((int)vector[i]) : INT_MAX + (uint32_t)1;
+    if (absolute > maximum) {
+      maximum = absolute;
+    }
+  }
+
+  maximum = WEBRTC_SPL_MIN(maximum, WEBRTC_SPL_WORD32_MAX);
+
+  return (int32_t)maximum;
+}
+
+// Maximum value of word16 vector. C version for generic platforms.
+int16_t WebRtcSpl_MaxValueW16C(const int16_t* vector, size_t length) {
+  int16_t maximum = WEBRTC_SPL_WORD16_MIN;
+  size_t i = 0;
+
+  RTC_DCHECK_GT(length, 0);
+
+  for (i = 0; i < length; i++) {
+    if (vector[i] > maximum)
+      maximum = vector[i];
+  }
+  return maximum;
+}
+
+// Maximum value of word32 vector. C version for generic platforms.
+int32_t WebRtcSpl_MaxValueW32C(const int32_t* vector, size_t length) {
+  int32_t maximum = WEBRTC_SPL_WORD32_MIN;
+  size_t i = 0;
+
+  RTC_DCHECK_GT(length, 0);
+
+  for (i = 0; i < length; i++) {
+    if (vector[i] > maximum)
+      maximum = vector[i];
+  }
+  return maximum;
+}
+
+// Minimum value of word16 vector. C version for generic platforms.
+int16_t WebRtcSpl_MinValueW16C(const int16_t* vector, size_t length) {
+  int16_t minimum = WEBRTC_SPL_WORD16_MAX;
+  size_t i = 0;
+
+  RTC_DCHECK_GT(length, 0);
+
+  for (i = 0; i < length; i++) {
+    if (vector[i] < minimum)
+      minimum = vector[i];
+  }
+  return minimum;
+}
+
+// Minimum value of word32 vector. C version for generic platforms.
+int32_t WebRtcSpl_MinValueW32C(const int32_t* vector, size_t length) {
+  int32_t minimum = WEBRTC_SPL_WORD32_MAX;
+  size_t i = 0;
+
+  RTC_DCHECK_GT(length, 0);
+
+  for (i = 0; i < length; i++) {
+    if (vector[i] < minimum)
+      minimum = vector[i];
+  }
+  return minimum;
+}
+
+// Index of maximum absolute value in a word16 vector.
+size_t WebRtcSpl_MaxAbsIndexW16(const int16_t* vector, size_t length) {
+  // Use type int for local variables, to accomodate the value of abs(-32768).
+
+  size_t i = 0, index = 0;
+  int absolute = 0, maximum = 0;
+
+  RTC_DCHECK_GT(length, 0);
+
+  for (i = 0; i < length; i++) {
+    absolute = abs((int)vector[i]);
+
+    if (absolute > maximum) {
+      maximum = absolute;
+      index = i;
+    }
+  }
+
+  return index;
+}
+
+int16_t WebRtcSpl_MaxAbsElementW16(const int16_t* vector, size_t length) {
+  int16_t min_val, max_val;
+  WebRtcSpl_MinMaxW16(vector, length, &min_val, &max_val);
+  if (min_val == max_val || min_val < -max_val) {
+    return min_val;
+  }
+  return max_val;
+}
+
+// Index of maximum value in a word16 vector.
+size_t WebRtcSpl_MaxIndexW16(const int16_t* vector, size_t length) {
+  size_t i = 0, index = 0;
+  int16_t maximum = WEBRTC_SPL_WORD16_MIN;
+
+  RTC_DCHECK_GT(length, 0);
+
+  for (i = 0; i < length; i++) {
+    if (vector[i] > maximum) {
+      maximum = vector[i];
+      index = i;
+    }
+  }
+
+  return index;
+}
+
+// Index of maximum value in a word32 vector.
+size_t WebRtcSpl_MaxIndexW32(const int32_t* vector, size_t length) {
+  size_t i = 0, index = 0;
+  int32_t maximum = WEBRTC_SPL_WORD32_MIN;
+
+  RTC_DCHECK_GT(length, 0);
+
+  for (i = 0; i < length; i++) {
+    if (vector[i] > maximum) {
+      maximum = vector[i];
+      index = i;
+    }
+  }
+
+  return index;
+}
+
+// Index of minimum value in a word16 vector.
+size_t WebRtcSpl_MinIndexW16(const int16_t* vector, size_t length) {
+  size_t i = 0, index = 0;
+  int16_t minimum = WEBRTC_SPL_WORD16_MAX;
+
+  RTC_DCHECK_GT(length, 0);
+
+  for (i = 0; i < length; i++) {
+    if (vector[i] < minimum) {
+      minimum = vector[i];
+      index = i;
+    }
+  }
+
+  return index;
+}
+
+// Index of minimum value in a word32 vector.
+size_t WebRtcSpl_MinIndexW32(const int32_t* vector, size_t length) {
+  size_t i = 0, index = 0;
+  int32_t minimum = WEBRTC_SPL_WORD32_MAX;
+
+  RTC_DCHECK_GT(length, 0);
+
+  for (i = 0; i < length; i++) {
+    if (vector[i] < minimum) {
+      minimum = vector[i];
+      index = i;
+    }
+  }
+
+  return index;
+}
+
+// Finds both the minimum and maximum elements in an array of 16-bit integers.
+void WebRtcSpl_MinMaxW16(const int16_t* vector, size_t length,
+                         int16_t* min_val, int16_t* max_val) {
+#if defined(WEBRTC_HAS_NEON)
+  return WebRtcSpl_MinMaxW16Neon(vector, length, min_val, max_val);
+#else
+  int16_t minimum = WEBRTC_SPL_WORD16_MAX;
+  int16_t maximum = WEBRTC_SPL_WORD16_MIN;
+  size_t i = 0;
+
+  RTC_DCHECK_GT(length, 0);
+
+  for (i = 0; i < length; i++) {
+    if (vector[i] < minimum)
+      minimum = vector[i];
+    if (vector[i] > maximum)
+      maximum = vector[i];
+  }
+  *min_val = minimum;
+  *max_val = maximum;
+#endif
+}

VocieProcess/common_audio/signal_processing/randomization_functions.c

@@ -0,0 +1,115 @@
+/*
+ *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+
+/*
+ * This file contains implementations of the randomization functions
+ * WebRtcSpl_RandU()
+ * WebRtcSpl_RandN()
+ * WebRtcSpl_RandUArray()
+ *
+ * The description header can be found in signal_processing_library.h
+ *
+ */
+
+#include "common_audio/signal_processing/include/signal_processing_library.h"
+
+static const uint32_t kMaxSeedUsed = 0x80000000;
+
+static const int16_t kRandNTable[] = {
+    9178,    -7260,       40,    10189,     4894,    -3531,   -13779,    14764,
+   -4008,    -8884,    -8990,     1008,     7368,     5184,     3251,    -5817,
+   -9786,     5963,     1770,     8066,    -7135,    10772,    -2298,     1361,
+    6484,     2241,    -8633,      792,      199,    -3344,     6553,   -10079,
+  -15040,       95,    11608,   -12469,    14161,    -4176,     2476,     6403,
+   13685,   -16005,     6646,     2239,    10916,    -3004,     -602,    -3141,
+    2142,    14144,    -5829,     5305,     8209,     4713,     2697,    -5112,
+   16092,    -1210,    -2891,    -6631,    -5360,   -11878,    -6781,    -2739,
+   -6392,      536,    10923,    10872,     5059,    -4748,    -7770,     5477,
+      38,    -1025,    -2892,     1638,     6304,    14375,   -11028,     1553,
+   -1565,    10762,     -393,     4040,     5257,    12310,     6554,    -4799,
+    4899,    -6354,     1603,    -1048,    -2220,     8247,     -186,    -8944,
+  -12004,     2332,     4801,    -4933,     6371,      131,     8614,    -5927,
+   -8287,   -22760,     4033,   -15162,     3385,     3246,     3153,    -5250,
+    3766,      784,     6494,      -62,     3531,    -1582,    15572,      662,
+   -3952,     -330,    -3196,      669,     7236,    -2678,    -6569,    23319,
+   -8645,     -741,    14830,   -15976,     4903,      315,   -11342,    10311,
+    1858,    -7777,     2145,     5436,     5677,     -113,   -10033,      826,
+   -1353,    17210,     7768,      986,    -1471,     8291,    -4982,     8207,
+  -14911,    -6255,    -2449,   -11881,    -7059,   -11703,    -4338,     8025,
+    7538,    -2823,   -12490,     9470,    -1613,    -2529,   -10092,    -7807,
+    9480,     6970,   -12844,     5123,     3532,     4816,     4803,    -8455,
+   -5045,    14032,    -4378,    -1643,     5756,   -11041,    -2732,   -16618,
+   -6430,   -18375,    -3320,     6098,     5131,    -4269,    -8840,     2482,
+   -7048,     1547,   -21890,    -6505,    -7414,     -424,   -11722,     7955,
+    1653,   -17299,     1823,      473,    -9232,     3337,     1111,      873,
+    4018,    -8982,     9889,     3531,   -11763,    -3799,     7373,    -4539,
+    3231,     7054,    -8537,     7616,     6244,    16635,      447,    -2915,
+   13967,      705,    -2669,    -1520,    -1771,   -16188,     5956,     5117,
+    6371,    -9936,    -1448,     2480,     5128,     7550,    -8130,     5236,
+    8213,    -6443,     7707,    -1950,   -13811,     7218,     7031,    -3883,
+      67,     5731,    -2874,    13480,    -3743,     9298,    -3280,     3552,
+   -4425,      -18,    -3785,    -9988,    -5357,     5477,   -11794,     2117,
+    1416,    -9935,     3376,      802,    -5079,    -8243,    12652,       66,
+    3653,    -2368,     6781,   -21895,    -7227,     2487,     7839,     -385,
+    6646,    -7016,    -4658,     5531,    -1705,      834,      129,     3694,
+   -1343,     2238,   -22640,    -6417,   -11139,    11301,    -2945,    -3494,
+   -5626,      185,    -3615,    -2041,    -7972,    -3106,      -60,   -23497,
+   -1566,    17064,     3519,     2518,      304,    -6805,   -10269,     2105,
+    1936,     -426,     -736,    -8122,    -1467,     4238,    -6939,   -13309,
+     360,     7402,    -7970,    12576,     3287,    12194,    -6289,   -16006,
+    9171,     4042,    -9193,     9123,    -2512,     6388,    -4734,    -8739,
+    1028,    -5406,    -1696,     5889,     -666,    -4736,     4971,     3565,
+    9362,    -6292,     3876,    -3652,   -19666,     7523,    -4061,      391,
+  -11773,     7502,    -3763,     4929,    -9478,    13278,     2805,     4496,
+    7814,    16419,    12455,   -14773,     2127,    -2746,     3763,     4847,
+    3698,     6978,     4751,    -6957,    -3581,      -45,     6252,     1513,
+   -4797,    -7925,    11270,    16188,    -2359,    -5269,     9376,   -10777,
+    7262,    20031,    -6515,    -2208,    -5353,     8085,    -1341,    -1303,
+    7333,     5576,     3625,     5763,    -7931,     9833,    -3371,   -10305,
+    6534,   -13539,    -9971,      997,     8464,    -4064,    -1495,     1857,
+   13624,     5458,     9490,   -11086,    -4524,    12022,     -550,     -198,
+     408,    -8455,    -7068,    10289,     9712,    -3366,     9028,    -7621,
+   -5243,     2362,     6909,     4672,    -4933,    -1799,     4709,    -4563,
+     -62,     -566,     1624,    -7010,    14730,   -17791,    -3697,    -2344,
+   -1741,     7099,    -9509,    -6855,    -1989,     3495,    -2289,     2031,
+   12784,      891,    14189,    -3963,    -5683,      421,   -12575,     1724,
+  -12682,    -5970,    -8169,     3143,    -1824,    -5488,    -5130,     8536,
+   12799,      794,     5738,     3459,   -11689,     -258,    -3738,    -3775,
+   -8742,     2333,     8312,    -9383,    10331,    13119,     8398,    10644,
+  -19433,    -6446,   -16277,   -11793,    16284,     9345,    15222,    15834,
+    2009,    -7349,      130,   -14547,      338,    -5998,     3337,    21492,
+    2406,     7703,     -951,    11196,     -564,     3406,     2217,     4806,
+    2374,    -5797,    11839,     8940,   -11874,    18213,     2855,    10492
+};
+
+static uint32_t IncreaseSeed(uint32_t* seed) {
+  seed[0] = (seed[0] * ((int32_t)69069) + 1) & (kMaxSeedUsed - 1);
+  return seed[0];
+}
+
+int16_t WebRtcSpl_RandU(uint32_t* seed) {
+  return (int16_t)(IncreaseSeed(seed) >> 16);
+}
+
+int16_t WebRtcSpl_RandN(uint32_t* seed) {
+  return kRandNTable[IncreaseSeed(seed) >> 23];
+}
+
+// Creates an array of uniformly distributed variables.
+int16_t WebRtcSpl_RandUArray(int16_t* vector,
+                             int16_t vector_length,
+                             uint32_t* seed) {
+  int i;
+  for (i = 0; i < vector_length; i++) {
+    vector[i] = WebRtcSpl_RandU(seed);
+  }
+  return vector_length;
+}

VocieProcess/common_audio/signal_processing/real_fft.c

@@ -0,0 +1,102 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "common_audio/signal_processing/include/real_fft.h"
+
+#include <stdlib.h>
+
+#include "common_audio/signal_processing/include/signal_processing_library.h"
+
+struct RealFFT {
+  int order;
+};
+
+struct RealFFT* WebRtcSpl_CreateRealFFT(int order) {
+  struct RealFFT* self = NULL;
+
+  if (order > kMaxFFTOrder || order < 0) {
+    return NULL;
+  }
+
+  self = malloc(sizeof(struct RealFFT));
+  if (self == NULL) {
+    return NULL;
+  }
+  self->order = order;
+
+  return self;
+}
+
+void WebRtcSpl_FreeRealFFT(struct RealFFT* self) {
+  if (self != NULL) {
+    free(self);
+  }
+}
+
+// The C version FFT functions (i.e. WebRtcSpl_RealForwardFFT and
+// WebRtcSpl_RealInverseFFT) are real-valued FFT wrappers for complex-valued
+// FFT implementation in SPL.
+
+int WebRtcSpl_RealForwardFFT(struct RealFFT* self,
+                             const int16_t* real_data_in,
+                             int16_t* complex_data_out) {
+  int i = 0;
+  int j = 0;
+  int result = 0;
+  int n = 1 << self->order;
+  // The complex-value FFT implementation needs a buffer to hold 2^order
+  // 16-bit COMPLEX numbers, for both time and frequency data.
+  int16_t complex_buffer[2 << kMaxFFTOrder];
+
+  // Insert zeros to the imaginary parts for complex forward FFT input.
+  for (i = 0, j = 0; i < n; i += 1, j += 2) {
+    complex_buffer[j] = real_data_in[i];
+    complex_buffer[j + 1] = 0;
+  };
+
+  WebRtcSpl_ComplexBitReverse(complex_buffer, self->order);
+  result = WebRtcSpl_ComplexFFT(complex_buffer, self->order, 1);
+
+  // For real FFT output, use only the first N + 2 elements from
+  // complex forward FFT.
+  memcpy(complex_data_out, complex_buffer, sizeof(int16_t) * (n + 2));
+
+  return result;
+}
+
+int WebRtcSpl_RealInverseFFT(struct RealFFT* self,
+                             const int16_t* complex_data_in,
+                             int16_t* real_data_out) {
+  int i = 0;
+  int j = 0;
+  int result = 0;
+  int n = 1 << self->order;
+  // Create the buffer specific to complex-valued FFT implementation.
+  int16_t complex_buffer[2 << kMaxFFTOrder];
+
+  // For n-point FFT, first copy the first n + 2 elements into complex
+  // FFT, then construct the remaining n - 2 elements by real FFT's
+  // conjugate-symmetric properties.
+  memcpy(complex_buffer, complex_data_in, sizeof(int16_t) * (n + 2));
+  for (i = n + 2; i < 2 * n; i += 2) {
+    complex_buffer[i] = complex_data_in[2 * n - i];
+    complex_buffer[i + 1] = -complex_data_in[2 * n - i + 1];
+  }
+
+  WebRtcSpl_ComplexBitReverse(complex_buffer, self->order);
+  result = WebRtcSpl_ComplexIFFT(complex_buffer, self->order, 1);
+
+  // Strip out the imaginary parts of the complex inverse FFT output.
+  for (i = 0, j = 0; i < n; i += 1, j += 2) {
+    real_data_out[i] = complex_buffer[j];
+  }
+
+  return result;
+}

VocieProcess/common_audio/signal_processing/spl_init.c

@@ -0,0 +1,69 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+// Some code came from common/rtcd.c in the WebM project.
+
+#include "common_audio/signal_processing/include/signal_processing_library.h"
+
+// TODO(bugs.webrtc.org/9553): These function pointers are useless. Refactor
+// things so that we simply have a bunch of regular functions with different
+// implementations for different platforms.
+
+#if defined(WEBRTC_HAS_NEON)
+
+const MaxAbsValueW16 WebRtcSpl_MaxAbsValueW16 = WebRtcSpl_MaxAbsValueW16Neon;
+const MaxAbsValueW32 WebRtcSpl_MaxAbsValueW32 = WebRtcSpl_MaxAbsValueW32Neon;
+const MaxValueW16 WebRtcSpl_MaxValueW16 = WebRtcSpl_MaxValueW16Neon;
+const MaxValueW32 WebRtcSpl_MaxValueW32 = WebRtcSpl_MaxValueW32Neon;
+const MinValueW16 WebRtcSpl_MinValueW16 = WebRtcSpl_MinValueW16Neon;
+const MinValueW32 WebRtcSpl_MinValueW32 = WebRtcSpl_MinValueW32Neon;
+const CrossCorrelation WebRtcSpl_CrossCorrelation =
+    WebRtcSpl_CrossCorrelationNeon;
+const DownsampleFast WebRtcSpl_DownsampleFast = WebRtcSpl_DownsampleFastNeon;
+const ScaleAndAddVectorsWithRound WebRtcSpl_ScaleAndAddVectorsWithRound =
+    WebRtcSpl_ScaleAndAddVectorsWithRoundC;
+
+#elif defined(MIPS32_LE)
+
+const MaxAbsValueW16 WebRtcSpl_MaxAbsValueW16 = WebRtcSpl_MaxAbsValueW16_mips;
+const MaxAbsValueW32 WebRtcSpl_MaxAbsValueW32 =
+#ifdef MIPS_DSP_R1_LE
+    WebRtcSpl_MaxAbsValueW32_mips;
+#else
+    WebRtcSpl_MaxAbsValueW32C;
+#endif
+const MaxValueW16 WebRtcSpl_MaxValueW16 = WebRtcSpl_MaxValueW16_mips;
+const MaxValueW32 WebRtcSpl_MaxValueW32 = WebRtcSpl_MaxValueW32_mips;
+const MinValueW16 WebRtcSpl_MinValueW16 = WebRtcSpl_MinValueW16_mips;
+const MinValueW32 WebRtcSpl_MinValueW32 = WebRtcSpl_MinValueW32_mips;
+const CrossCorrelation WebRtcSpl_CrossCorrelation =
+    WebRtcSpl_CrossCorrelation_mips;
+const DownsampleFast WebRtcSpl_DownsampleFast = WebRtcSpl_DownsampleFast_mips;
+const ScaleAndAddVectorsWithRound WebRtcSpl_ScaleAndAddVectorsWithRound =
+#ifdef MIPS_DSP_R1_LE
+    WebRtcSpl_ScaleAndAddVectorsWithRound_mips;
+#else
+    WebRtcSpl_ScaleAndAddVectorsWithRoundC;
+#endif
+
+#else
+
+const MaxAbsValueW16 WebRtcSpl_MaxAbsValueW16 = WebRtcSpl_MaxAbsValueW16C;
+const MaxAbsValueW32 WebRtcSpl_MaxAbsValueW32 = WebRtcSpl_MaxAbsValueW32C;
+const MaxValueW16 WebRtcSpl_MaxValueW16 = WebRtcSpl_MaxValueW16C;
+const MaxValueW32 WebRtcSpl_MaxValueW32 = WebRtcSpl_MaxValueW32C;
+const MinValueW16 WebRtcSpl_MinValueW16 = WebRtcSpl_MinValueW16C;
+const MinValueW32 WebRtcSpl_MinValueW32 = WebRtcSpl_MinValueW32C;
+const CrossCorrelation WebRtcSpl_CrossCorrelation = WebRtcSpl_CrossCorrelationC;
+const DownsampleFast WebRtcSpl_DownsampleFast = WebRtcSpl_DownsampleFastC;
+const ScaleAndAddVectorsWithRound WebRtcSpl_ScaleAndAddVectorsWithRound =
+    WebRtcSpl_ScaleAndAddVectorsWithRoundC;
+
+#endif

VocieProcess/common_audio/signal_processing/vector_scaling_operations.c

@@ -0,0 +1,165 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+
+/*
+ * This file contains implementations of the functions
+ * WebRtcSpl_VectorBitShiftW16()
+ * WebRtcSpl_VectorBitShiftW32()
+ * WebRtcSpl_VectorBitShiftW32ToW16()
+ * WebRtcSpl_ScaleVector()
+ * WebRtcSpl_ScaleVectorWithSat()
+ * WebRtcSpl_ScaleAndAddVectors()
+ * WebRtcSpl_ScaleAndAddVectorsWithRoundC()
+ */
+
+#include "common_audio/signal_processing/include/signal_processing_library.h"
+
+void WebRtcSpl_VectorBitShiftW16(int16_t *res, size_t length,
+                                 const int16_t *in, int16_t right_shifts)
+{
+    size_t i;
+
+    if (right_shifts > 0)
+    {
+        for (i = length; i > 0; i--)
+        {
+            (*res++) = ((*in++) >> right_shifts);
+        }
+    } else
+    {
+        for (i = length; i > 0; i--)
+        {
+            (*res++) = ((*in++) * (1 << (-right_shifts)));
+        }
+    }
+}
+
+void WebRtcSpl_VectorBitShiftW32(int32_t *out_vector,
+                                 size_t vector_length,
+                                 const int32_t *in_vector,
+                                 int16_t right_shifts)
+{
+    size_t i;
+
+    if (right_shifts > 0)
+    {
+        for (i = vector_length; i > 0; i--)
+        {
+            (*out_vector++) = ((*in_vector++) >> right_shifts);
+        }
+    } else
+    {
+        for (i = vector_length; i > 0; i--)
+        {
+            (*out_vector++) = ((*in_vector++) << (-right_shifts));
+        }
+    }
+}
+
+void WebRtcSpl_VectorBitShiftW32ToW16(int16_t* out, size_t length,
+                                      const int32_t* in, int right_shifts) {
+  size_t i;
+  int32_t tmp_w32;
+
+  if (right_shifts >= 0) {
+    for (i = length; i > 0; i--) {
+      tmp_w32 = (*in++) >> right_shifts;
+      (*out++) = WebRtcSpl_SatW32ToW16(tmp_w32);
+    }
+  } else {
+    int left_shifts = -right_shifts;
+    for (i = length; i > 0; i--) {
+      tmp_w32 = (*in++) << left_shifts;
+      (*out++) = WebRtcSpl_SatW32ToW16(tmp_w32);
+    }
+  }
+}
+
+void WebRtcSpl_ScaleVector(const int16_t *in_vector, int16_t *out_vector,
+                           int16_t gain, size_t in_vector_length,
+                           int16_t right_shifts)
+{
+    // Performs vector operation: out_vector = (gain*in_vector)>>right_shifts
+    size_t i;
+    const int16_t *inptr;
+    int16_t *outptr;
+
+    inptr = in_vector;
+    outptr = out_vector;
+
+    for (i = 0; i < in_vector_length; i++)
+    {
+      *outptr++ = (int16_t)((*inptr++ * gain) >> right_shifts);
+    }
+}
+
+void WebRtcSpl_ScaleVectorWithSat(const int16_t *in_vector, int16_t *out_vector,
+                                 int16_t gain, size_t in_vector_length,
+                                 int16_t right_shifts)
+{
+    // Performs vector operation: out_vector = (gain*in_vector)>>right_shifts
+    size_t i;
+    const int16_t *inptr;
+    int16_t *outptr;
+
+    inptr = in_vector;
+    outptr = out_vector;
+
+    for (i = 0; i < in_vector_length; i++) {
+      *outptr++ = WebRtcSpl_SatW32ToW16((*inptr++ * gain) >> right_shifts);
+    }
+}
+
+void WebRtcSpl_ScaleAndAddVectors(const int16_t *in1, int16_t gain1, int shift1,
+                                  const int16_t *in2, int16_t gain2, int shift2,
+                                  int16_t *out, size_t vector_length)
+{
+    // Performs vector operation: out = (gain1*in1)>>shift1 + (gain2*in2)>>shift2
+    size_t i;
+    const int16_t *in1ptr;
+    const int16_t *in2ptr;
+    int16_t *outptr;
+
+    in1ptr = in1;
+    in2ptr = in2;
+    outptr = out;
+
+    for (i = 0; i < vector_length; i++)
+    {
+      *outptr++ = (int16_t)((gain1 * *in1ptr++) >> shift1) +
+          (int16_t)((gain2 * *in2ptr++) >> shift2);
+    }
+}
+
+// C version of WebRtcSpl_ScaleAndAddVectorsWithRound() for generic platforms.
+int WebRtcSpl_ScaleAndAddVectorsWithRoundC(const int16_t* in_vector1,
+                                           int16_t in_vector1_scale,
+                                           const int16_t* in_vector2,
+                                           int16_t in_vector2_scale,
+                                           int right_shifts,
+                                           int16_t* out_vector,
+                                           size_t length) {
+  size_t i = 0;
+  int round_value = (1 << right_shifts) >> 1;
+
+  if (in_vector1 == NULL || in_vector2 == NULL || out_vector == NULL ||
+      length == 0 || right_shifts < 0) {
+    return -1;
+  }
+
+  for (i = 0; i < length; i++) {
+    out_vector[i] = (int16_t)((
+        in_vector1[i] * in_vector1_scale + in_vector2[i] * in_vector2_scale +
+        round_value) >> right_shifts);
+  }
+
+  return 0;
+}

VocieProcess/modules/audio_processing/aecm/aecm_core.h

@@ -0,0 +1,441 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+// Performs echo control (suppression) with fft routines in fixed-point.
+
+#ifndef MODULES_AUDIO_PROCESSING_AECM_AECM_CORE_H_
+#define MODULES_AUDIO_PROCESSING_AECM_AECM_CORE_H_
+
+extern "C" {
+#include "common_audio/ring_buffer.h"
+#include "common_audio/signal_processing/include/signal_processing_library.h"
+}
+#include "modules/audio_processing/aecm/aecm_defines.h"
+
+struct RealFFT;
+
+namespace webrtc {
+
+#ifdef _MSC_VER  // visual c++
+#define ALIGN8_BEG __declspec(align(8))
+#define ALIGN8_END
+#else  // gcc or icc
+#define ALIGN8_BEG
+#define ALIGN8_END __attribute__((aligned(8)))
+#endif
+
+typedef struct {
+  int16_t real;
+  int16_t imag;
+} ComplexInt16;
+
+typedef struct {
+  int farBufWritePos;
+  int farBufReadPos;
+  int knownDelay;
+  int lastKnownDelay;
+  int firstVAD;  // Parameter to control poorly initialized channels
+
+  RingBuffer* farFrameBuf;
+  RingBuffer* nearNoisyFrameBuf;
+  RingBuffer* nearCleanFrameBuf;
+  RingBuffer* outFrameBuf;
+
+  int16_t farBuf[FAR_BUF_LEN];
+
+  int16_t mult;
+  uint32_t seed;
+
+  // Delay estimation variables
+  void* delay_estimator_farend;
+  void* delay_estimator;
+  uint16_t currentDelay;
+  // Far end history variables
+  // TODO(bjornv): Replace `far_history` with ring_buffer.
+  uint16_t far_history[PART_LEN1 * MAX_DELAY];
+  int far_history_pos;
+  int far_q_domains[MAX_DELAY];
+
+  int16_t nlpFlag;
+  int16_t fixedDelay;
+
+  uint32_t totCount;
+
+  int16_t dfaCleanQDomain;
+  int16_t dfaCleanQDomainOld;
+  int16_t dfaNoisyQDomain;
+  int16_t dfaNoisyQDomainOld;
+
+  int16_t nearLogEnergy[MAX_BUF_LEN];
+  int16_t farLogEnergy;
+  int16_t echoAdaptLogEnergy[MAX_BUF_LEN];
+  int16_t echoStoredLogEnergy[MAX_BUF_LEN];
+
+  // The extra 16 or 32 bytes in the following buffers are for alignment based
+  // Neon code.
+  // It's designed this way since the current GCC compiler can't align a
+  // buffer in 16 or 32 byte boundaries properly.
+  int16_t channelStored_buf[PART_LEN1 + 8];
+  int16_t channelAdapt16_buf[PART_LEN1 + 8];
+  int32_t channelAdapt32_buf[PART_LEN1 + 8];
+  int16_t xBuf_buf[PART_LEN2 + 16];       // farend
+  int16_t dBufClean_buf[PART_LEN2 + 16];  // nearend
+  int16_t dBufNoisy_buf[PART_LEN2 + 16];  // nearend
+  int16_t outBuf_buf[PART_LEN + 8];
+
+  // Pointers to the above buffers
+  int16_t* channelStored;
+  int16_t* channelAdapt16;
+  int32_t* channelAdapt32;
+  int16_t* xBuf;
+  int16_t* dBufClean;
+  int16_t* dBufNoisy;
+  int16_t* outBuf;
+
+  int32_t echoFilt[PART_LEN1];
+  int16_t nearFilt[PART_LEN1];
+  int32_t noiseEst[PART_LEN1];
+  int noiseEstTooLowCtr[PART_LEN1];
+  int noiseEstTooHighCtr[PART_LEN1];
+  int16_t noiseEstCtr;
+  int16_t cngMode;
+
+  int32_t mseAdaptOld;
+  int32_t mseStoredOld;
+  int32_t mseThreshold;
+
+  int16_t farEnergyMin;
+  int16_t farEnergyMax;
+  int16_t farEnergyMaxMin;
+  int16_t farEnergyVAD;
+  int16_t farEnergyMSE;
+  int currentVADValue;
+  int16_t vadUpdateCount;
+
+  int16_t startupState;
+  int16_t mseChannelCount;
+  int16_t supGain;
+  int16_t supGainOld;
+
+  int16_t supGainErrParamA;
+  int16_t supGainErrParamD;
+  int16_t supGainErrParamDiffAB;
+  int16_t supGainErrParamDiffBD;
+
+  struct RealFFT* real_fft;
+
+#ifdef AEC_DEBUG
+  FILE* farFile;
+  FILE* nearFile;
+  FILE* outFile;
+#endif
+} AecmCore;
+
+////////////////////////////////////////////////////////////////////////////////
+// WebRtcAecm_CreateCore()
+//
+// Allocates the memory needed by the AECM. The memory needs to be
+// initialized separately using the WebRtcAecm_InitCore() function.
+// Returns a pointer to the instance and a nullptr at failure.
+AecmCore* WebRtcAecm_CreateCore();
+
+////////////////////////////////////////////////////////////////////////////////
+// WebRtcAecm_InitCore(...)
+//
+// This function initializes the AECM instant created with
+// WebRtcAecm_CreateCore()
+// Input:
+//      - aecm          : Pointer to the AECM instance
+//      - samplingFreq  : Sampling Frequency
+//
+// Output:
+//      - aecm          : Initialized instance
+//
+// Return value         :  0 - Ok
+//                        -1 - Error
+//
+int WebRtcAecm_InitCore(AecmCore* const aecm, int samplingFreq);
+
+////////////////////////////////////////////////////////////////////////////////
+// WebRtcAecm_FreeCore(...)
+//
+// This function releases the memory allocated by WebRtcAecm_CreateCore()
+// Input:
+//      - aecm          : Pointer to the AECM instance
+//
+void WebRtcAecm_FreeCore(AecmCore* aecm);
+
+int WebRtcAecm_Control(AecmCore* aecm, int delay, int nlpFlag);
+
+////////////////////////////////////////////////////////////////////////////////
+// WebRtcAecm_InitEchoPathCore(...)
+//
+// This function resets the echo channel adaptation with the specified channel.
+// Input:
+//      - aecm          : Pointer to the AECM instance
+//      - echo_path     : Pointer to the data that should initialize the echo
+//                        path
+//
+// Output:
+//      - aecm          : Initialized instance
+//
+void WebRtcAecm_InitEchoPathCore(AecmCore* aecm, const int16_t* echo_path);
+
+////////////////////////////////////////////////////////////////////////////////
+// WebRtcAecm_ProcessFrame(...)
+//
+// This function processes frames and sends blocks to
+// WebRtcAecm_ProcessBlock(...)
+//
+// Inputs:
+//      - aecm          : Pointer to the AECM instance
+//      - farend        : In buffer containing one frame of echo signal
+//      - nearendNoisy  : In buffer containing one frame of nearend+echo signal
+//                        without NS
+//      - nearendClean  : In buffer containing one frame of nearend+echo signal
+//                        with NS
+//
+// Output:
+//      - out           : Out buffer, one frame of nearend signal          :
+//
+//
+int WebRtcAecm_ProcessFrame(AecmCore* aecm,
+                            const int16_t* farend,
+                            const int16_t* nearendNoisy,
+                            const int16_t* nearendClean,
+                            int16_t* out);
+
+////////////////////////////////////////////////////////////////////////////////
+// WebRtcAecm_ProcessBlock(...)
+//
+// This function is called for every block within one frame
+// This function is called by WebRtcAecm_ProcessFrame(...)
+//
+// Inputs:
+//      - aecm          : Pointer to the AECM instance
+//      - farend        : In buffer containing one block of echo signal
+//      - nearendNoisy  : In buffer containing one frame of nearend+echo signal
+//                        without NS
+//      - nearendClean  : In buffer containing one frame of nearend+echo signal
+//                        with NS
+//
+// Output:
+//      - out           : Out buffer, one block of nearend signal          :
+//
+//
+int WebRtcAecm_ProcessBlock(AecmCore* aecm,
+                            const int16_t* farend,
+                            const int16_t* nearendNoisy,
+                            const int16_t* noisyClean,
+                            int16_t* out);
+
+////////////////////////////////////////////////////////////////////////////////
+// WebRtcAecm_BufferFarFrame()
+//
+// Inserts a frame of data into farend buffer.
+//
+// Inputs:
+//      - aecm          : Pointer to the AECM instance
+//      - farend        : In buffer containing one frame of farend signal
+//      - farLen        : Length of frame
+//
+void WebRtcAecm_BufferFarFrame(AecmCore* const aecm,
+                               const int16_t* const farend,
+                               int farLen);
+
+////////////////////////////////////////////////////////////////////////////////
+// WebRtcAecm_FetchFarFrame()
+//
+// Read the farend buffer to account for known delay
+//
+// Inputs:
+//      - aecm          : Pointer to the AECM instance
+//      - farend        : In buffer containing one frame of farend signal
+//      - farLen        : Length of frame
+//      - knownDelay    : known delay
+//
+void WebRtcAecm_FetchFarFrame(AecmCore* const aecm,
+                              int16_t* const farend,
+                              int farLen,
+                              int knownDelay);
+
+// All the functions below are intended to be private
+
+////////////////////////////////////////////////////////////////////////////////
+// WebRtcAecm_UpdateFarHistory()
+//
+// Moves the pointer to the next entry and inserts `far_spectrum` and
+// corresponding Q-domain in its buffer.
+//
+// Inputs:
+//      - self          : Pointer to the delay estimation instance
+//      - far_spectrum  : Pointer to the far end spectrum
+//      - far_q         : Q-domain of far end spectrum
+//
+void WebRtcAecm_UpdateFarHistory(AecmCore* self,
+                                 uint16_t* far_spectrum,
+                                 int far_q);
+
+////////////////////////////////////////////////////////////////////////////////
+// WebRtcAecm_AlignedFarend()
+//
+// Returns a pointer to the far end spectrum aligned to current near end
+// spectrum. The function WebRtc_DelayEstimatorProcessFix(...) should have been
+// called before AlignedFarend(...). Otherwise, you get the pointer to the
+// previous frame. The memory is only valid until the next call of
+// WebRtc_DelayEstimatorProcessFix(...).
+//
+// Inputs:
+//      - self              : Pointer to the AECM instance.
+//      - delay             : Current delay estimate.
+//
+// Output:
+//      - far_q             : The Q-domain of the aligned far end spectrum
+//
+// Return value:
+//      - far_spectrum      : Pointer to the aligned far end spectrum
+//                            NULL - Error
+//
+const uint16_t* WebRtcAecm_AlignedFarend(AecmCore* self, int* far_q, int delay);
+
+///////////////////////////////////////////////////////////////////////////////
+// WebRtcAecm_CalcSuppressionGain()
+//
+// This function calculates the suppression gain that is used in the
+// Wiener filter.
+//
+// Inputs:
+//      - aecm              : Pointer to the AECM instance.
+//
+// Return value:
+//      - supGain           : Suppression gain with which to scale the noise
+//                            level (Q14).
+//
+int16_t WebRtcAecm_CalcSuppressionGain(AecmCore* const aecm);
+
+///////////////////////////////////////////////////////////////////////////////
+// WebRtcAecm_CalcEnergies()
+//
+// This function calculates the log of energies for nearend, farend and
+// estimated echoes. There is also an update of energy decision levels,
+// i.e. internal VAD.
+//
+// Inputs:
+//      - aecm              : Pointer to the AECM instance.
+//      - far_spectrum      : Pointer to farend spectrum.
+//      - far_q             : Q-domain of farend spectrum.
+//      - nearEner          : Near end energy for current block in
+//                            Q(aecm->dfaQDomain).
+//
+// Output:
+//     - echoEst            : Estimated echo in Q(xfa_q+RESOLUTION_CHANNEL16).
+//
+void WebRtcAecm_CalcEnergies(AecmCore* aecm,
+                             const uint16_t* far_spectrum,
+                             int16_t far_q,
+                             uint32_t nearEner,
+                             int32_t* echoEst);
+
+///////////////////////////////////////////////////////////////////////////////
+// WebRtcAecm_CalcStepSize()
+//
+// This function calculates the step size used in channel estimation
+//
+// Inputs:
+//      - aecm              : Pointer to the AECM instance.
+//
+// Return value:
+//      - mu                : Stepsize in log2(), i.e. number of shifts.
+//
+int16_t WebRtcAecm_CalcStepSize(AecmCore* const aecm);
+
+///////////////////////////////////////////////////////////////////////////////
+// WebRtcAecm_UpdateChannel(...)
+//
+// This function performs channel estimation.
+// NLMS and decision on channel storage.
+//
+// Inputs:
+//      - aecm              : Pointer to the AECM instance.
+//      - far_spectrum      : Absolute value of the farend signal in Q(far_q)
+//      - far_q             : Q-domain of the farend signal
+//      - dfa               : Absolute value of the nearend signal
+//                            (Q[aecm->dfaQDomain])
+//      - mu                : NLMS step size.
+// Input/Output:
+//      - echoEst           : Estimated echo in Q(far_q+RESOLUTION_CHANNEL16).
+//
+void WebRtcAecm_UpdateChannel(AecmCore* aecm,
+                              const uint16_t* far_spectrum,
+                              int16_t far_q,
+                              const uint16_t* const dfa,
+                              int16_t mu,
+                              int32_t* echoEst);
+
+extern const int16_t WebRtcAecm_kCosTable[];
+extern const int16_t WebRtcAecm_kSinTable[];
+
+///////////////////////////////////////////////////////////////////////////////
+// Some function pointers, for internal functions shared by ARM NEON and
+// generic C code.
+//
+typedef void (*CalcLinearEnergies)(AecmCore* aecm,
+                                   const uint16_t* far_spectrum,
+                                   int32_t* echoEst,
+                                   uint32_t* far_energy,
+                                   uint32_t* echo_energy_adapt,
+                                   uint32_t* echo_energy_stored);
+extern CalcLinearEnergies WebRtcAecm_CalcLinearEnergies;
+
+typedef void (*StoreAdaptiveChannel)(AecmCore* aecm,
+                                     const uint16_t* far_spectrum,
+                                     int32_t* echo_est);
+extern StoreAdaptiveChannel WebRtcAecm_StoreAdaptiveChannel;
+
+typedef void (*ResetAdaptiveChannel)(AecmCore* aecm);
+extern ResetAdaptiveChannel WebRtcAecm_ResetAdaptiveChannel;
+
+// For the above function pointers, functions for generic platforms are declared
+// and defined as static in file aecm_core.c, while those for ARM Neon platforms
+// are declared below and defined in file aecm_core_neon.c.
+#if defined(WEBRTC_HAS_NEON)
+void WebRtcAecm_CalcLinearEnergiesNeon(AecmCore* aecm,
+                                       const uint16_t* far_spectrum,
+                                       int32_t* echo_est,
+                                       uint32_t* far_energy,
+                                       uint32_t* echo_energy_adapt,
+                                       uint32_t* echo_energy_stored);
+
+void WebRtcAecm_StoreAdaptiveChannelNeon(AecmCore* aecm,
+                                         const uint16_t* far_spectrum,
+                                         int32_t* echo_est);
+
+void WebRtcAecm_ResetAdaptiveChannelNeon(AecmCore* aecm);
+#endif
+
+#if defined(MIPS32_LE)
+void WebRtcAecm_CalcLinearEnergies_mips(AecmCore* aecm,
+                                        const uint16_t* far_spectrum,
+                                        int32_t* echo_est,
+                                        uint32_t* far_energy,
+                                        uint32_t* echo_energy_adapt,
+                                        uint32_t* echo_energy_stored);
+#if defined(MIPS_DSP_R1_LE)
+void WebRtcAecm_StoreAdaptiveChannel_mips(AecmCore* aecm,
+                                          const uint16_t* far_spectrum,
+                                          int32_t* echo_est);
+
+void WebRtcAecm_ResetAdaptiveChannel_mips(AecmCore* aecm);
+#endif
+#endif
+
+}  // namespace webrtc
+
+#endif

VocieProcess/modules/audio_processing/aecm/aecm_core_c.cc

@@ -0,0 +1,672 @@
+/*
+ *  Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include <stddef.h>
+#include <stdlib.h>
+
+#include "modules/audio_processing/aecm/aecm_core.h"
+
+extern "C" {
+#include "common_audio/ring_buffer.h"
+#include "common_audio/signal_processing/include/real_fft.h"
+}
+#include "modules/audio_processing/aecm/echo_control_mobile.h"
+#include "modules/audio_processing/utility/delay_estimator_wrapper.h"
+extern "C" {
+#include "system_wrappers/include/cpu_features_wrapper.h"
+}
+
+#include "rtc_base/checks.h"
+#include "rtc_base/numerics/safe_conversions.h"
+#include "rtc_base/sanitizer.h"
+
+namespace webrtc {
+
+namespace {
+
+// Square root of Hanning window in Q14.
+static const ALIGN8_BEG int16_t WebRtcAecm_kSqrtHanning[] ALIGN8_END = {
+    0,     399,   798,   1196,  1594,  1990,  2386,  2780,  3172,  3562,  3951,
+    4337,  4720,  5101,  5478,  5853,  6224,  6591,  6954,  7313,  7668,  8019,
+    8364,  8705,  9040,  9370,  9695,  10013, 10326, 10633, 10933, 11227, 11514,
+    11795, 12068, 12335, 12594, 12845, 13089, 13325, 13553, 13773, 13985, 14189,
+    14384, 14571, 14749, 14918, 15079, 15231, 15373, 15506, 15631, 15746, 15851,
+    15947, 16034, 16111, 16179, 16237, 16286, 16325, 16354, 16373, 16384};
+
+#ifdef AECM_WITH_ABS_APPROX
+// Q15 alpha = 0.99439986968132  const Factor for magnitude approximation
+static const uint16_t kAlpha1 = 32584;
+// Q15 beta = 0.12967166976970   const Factor for magnitude approximation
+static const uint16_t kBeta1 = 4249;
+// Q15 alpha = 0.94234827210087  const Factor for magnitude approximation
+static const uint16_t kAlpha2 = 30879;
+// Q15 beta = 0.33787806009150   const Factor for magnitude approximation
+static const uint16_t kBeta2 = 11072;
+// Q15 alpha = 0.82247698684306  const Factor for magnitude approximation
+static const uint16_t kAlpha3 = 26951;
+// Q15 beta = 0.57762063060713   const Factor for magnitude approximation
+static const uint16_t kBeta3 = 18927;
+#endif
+
+static const int16_t kNoiseEstQDomain = 15;
+static const int16_t kNoiseEstIncCount = 5;
+
+static void ComfortNoise(AecmCore* aecm,
+                         const uint16_t* dfa,
+                         ComplexInt16* out,
+                         const int16_t* lambda) {
+  int16_t i;
+  int16_t tmp16;
+  int32_t tmp32;
+
+  int16_t randW16[PART_LEN];
+  int16_t uReal[PART_LEN1];
+  int16_t uImag[PART_LEN1];
+  int32_t outLShift32;
+  int16_t noiseRShift16[PART_LEN1];
+
+  int16_t shiftFromNearToNoise = kNoiseEstQDomain - aecm->dfaCleanQDomain;
+  int16_t minTrackShift;
+
+  RTC_DCHECK_GE(shiftFromNearToNoise, 0);
+  RTC_DCHECK_LT(shiftFromNearToNoise, 16);
+
+  if (aecm->noiseEstCtr < 100) {
+    // Track the minimum more quickly initially.
+    aecm->noiseEstCtr++;
+    minTrackShift = 6;
+  } else {
+    minTrackShift = 9;
+  }
+
+  // Estimate noise power.
+  for (i = 0; i < PART_LEN1; i++) {
+    // Shift to the noise domain.
+    tmp32 = (int32_t)dfa[i];
+    outLShift32 = tmp32 << shiftFromNearToNoise;
+
+    if (outLShift32 < aecm->noiseEst[i]) {
+      // Reset "too low" counter
+      aecm->noiseEstTooLowCtr[i] = 0;
+      // Track the minimum.
+      if (aecm->noiseEst[i] < (1 << minTrackShift)) {
+        // For small values, decrease noiseEst[i] every
+        // `kNoiseEstIncCount` block. The regular approach below can not
+        // go further down due to truncation.
+        aecm->noiseEstTooHighCtr[i]++;
+        if (aecm->noiseEstTooHighCtr[i] >= kNoiseEstIncCount) {
+          aecm->noiseEst[i]--;
+          aecm->noiseEstTooHighCtr[i] = 0;  // Reset the counter
+        }
+      } else {
+        aecm->noiseEst[i] -=
+            ((aecm->noiseEst[i] - outLShift32) >> minTrackShift);
+      }
+    } else {
+      // Reset "too high" counter
+      aecm->noiseEstTooHighCtr[i] = 0;
+      // Ramp slowly upwards until we hit the minimum again.
+      if ((aecm->noiseEst[i] >> 19) > 0) {
+        // Avoid overflow.
+        // Multiplication with 2049 will cause wrap around. Scale
+        // down first and then multiply
+        aecm->noiseEst[i] >>= 11;
+        aecm->noiseEst[i] *= 2049;
+      } else if ((aecm->noiseEst[i] >> 11) > 0) {
+        // Large enough for relative increase
+        aecm->noiseEst[i] *= 2049;
+        aecm->noiseEst[i] >>= 11;
+      } else {
+        // Make incremental increases based on size every
+        // `kNoiseEstIncCount` block
+        aecm->noiseEstTooLowCtr[i]++;
+        if (aecm->noiseEstTooLowCtr[i] >= kNoiseEstIncCount) {
+          aecm->noiseEst[i] += (aecm->noiseEst[i] >> 9) + 1;
+          aecm->noiseEstTooLowCtr[i] = 0;  // Reset counter
+        }
+      }
+    }
+  }
+
+  for (i = 0; i < PART_LEN1; i++) {
+    tmp32 = aecm->noiseEst[i] >> shiftFromNearToNoise;
+    if (tmp32 > 32767) {
+      tmp32 = 32767;
+      aecm->noiseEst[i] = tmp32 << shiftFromNearToNoise;
+    }
+    noiseRShift16[i] = (int16_t)tmp32;
+
+    tmp16 = ONE_Q14 - lambda[i];
+    noiseRShift16[i] = (int16_t)((tmp16 * noiseRShift16[i]) >> 14);
+  }
+
+  // Generate a uniform random array on [0 2^15-1].
+  WebRtcSpl_RandUArray(randW16, PART_LEN, &aecm->seed);
+
+  // Generate noise according to estimated energy.
+  uReal[0] = 0;  // Reject LF noise.
+  uImag[0] = 0;
+  for (i = 1; i < PART_LEN1; i++) {
+    // Get a random index for the cos and sin tables over [0 359].
+    tmp16 = (int16_t)((359 * randW16[i - 1]) >> 15);
+
+    // Tables are in Q13.
+    uReal[i] =
+        (int16_t)((noiseRShift16[i] * WebRtcAecm_kCosTable[tmp16]) >> 13);
+    uImag[i] =
+        (int16_t)((-noiseRShift16[i] * WebRtcAecm_kSinTable[tmp16]) >> 13);
+  }
+  uImag[PART_LEN] = 0;
+
+  for (i = 0; i < PART_LEN1; i++) {
+    out[i].real = WebRtcSpl_AddSatW16(out[i].real, uReal[i]);
+    out[i].imag = WebRtcSpl_AddSatW16(out[i].imag, uImag[i]);
+  }
+}
+
+static void WindowAndFFT(AecmCore* aecm,
+                         int16_t* fft,
+                         const int16_t* time_signal,
+                         ComplexInt16* freq_signal,
+                         int time_signal_scaling) {
+  int i = 0;
+
+  // FFT of signal
+  for (i = 0; i < PART_LEN; i++) {
+    // Window time domain signal and insert into real part of
+    // transformation array `fft`
+    int16_t scaled_time_signal = time_signal[i] * (1 << time_signal_scaling);
+    fft[i] = (int16_t)((scaled_time_signal * WebRtcAecm_kSqrtHanning[i]) >> 14);
+    scaled_time_signal = time_signal[i + PART_LEN] * (1 << time_signal_scaling);
+    fft[PART_LEN + i] = (int16_t)((scaled_time_signal *
+                                   WebRtcAecm_kSqrtHanning[PART_LEN - i]) >>
+                                  14);
+  }
+
+  // Do forward FFT, then take only the first PART_LEN complex samples,
+  // and change signs of the imaginary parts.
+  WebRtcSpl_RealForwardFFT(aecm->real_fft, fft, (int16_t*)freq_signal);
+  for (i = 0; i < PART_LEN; i++) {
+    freq_signal[i].imag = -freq_signal[i].imag;
+  }
+}
+
+static void InverseFFTAndWindow(AecmCore* aecm,
+                                int16_t* fft,
+                                ComplexInt16* efw,
+                                int16_t* output,
+                                const int16_t* nearendClean) {
+  int i, j, outCFFT;
+  int32_t tmp32no1;
+  // Reuse `efw` for the inverse FFT output after transferring
+  // the contents to `fft`.
+  int16_t* ifft_out = (int16_t*)efw;
+
+  // Synthesis
+  for (i = 1, j = 2; i < PART_LEN; i += 1, j += 2) {
+    fft[j] = efw[i].real;
+    fft[j + 1] = -efw[i].imag;
+  }
+  fft[0] = efw[0].real;
+  fft[1] = -efw[0].imag;
+
+  fft[PART_LEN2] = efw[PART_LEN].real;
+  fft[PART_LEN2 + 1] = -efw[PART_LEN].imag;
+
+  // Inverse FFT. Keep outCFFT to scale the samples in the next block.
+  outCFFT = WebRtcSpl_RealInverseFFT(aecm->real_fft, fft, ifft_out);
+  for (i = 0; i < PART_LEN; i++) {
+    ifft_out[i] = (int16_t)WEBRTC_SPL_MUL_16_16_RSFT_WITH_ROUND(
+        ifft_out[i], WebRtcAecm_kSqrtHanning[i], 14);
+    tmp32no1 = WEBRTC_SPL_SHIFT_W32((int32_t)ifft_out[i],
+                                    outCFFT - aecm->dfaCleanQDomain);
+    output[i] = (int16_t)WEBRTC_SPL_SAT(WEBRTC_SPL_WORD16_MAX,
+                                        tmp32no1 + aecm->outBuf[i],
+                                        WEBRTC_SPL_WORD16_MIN);
+
+    tmp32no1 =
+        (ifft_out[PART_LEN + i] * WebRtcAecm_kSqrtHanning[PART_LEN - i]) >> 14;
+    tmp32no1 = WEBRTC_SPL_SHIFT_W32(tmp32no1, outCFFT - aecm->dfaCleanQDomain);
+    aecm->outBuf[i] = (int16_t)WEBRTC_SPL_SAT(WEBRTC_SPL_WORD16_MAX, tmp32no1,
+                                              WEBRTC_SPL_WORD16_MIN);
+  }
+
+  // Copy the current block to the old position
+  // (aecm->outBuf is shifted elsewhere)
+  memcpy(aecm->xBuf, aecm->xBuf + PART_LEN, sizeof(int16_t) * PART_LEN);
+  memcpy(aecm->dBufNoisy, aecm->dBufNoisy + PART_LEN,
+         sizeof(int16_t) * PART_LEN);
+  if (nearendClean != NULL) {
+    memcpy(aecm->dBufClean, aecm->dBufClean + PART_LEN,
+           sizeof(int16_t) * PART_LEN);
+  }
+}
+
+// Transforms a time domain signal into the frequency domain, outputting the
+// complex valued signal, absolute value and sum of absolute values.
+//
+// time_signal          [in]    Pointer to time domain signal
+// freq_signal_real     [out]   Pointer to real part of frequency domain array
+// freq_signal_imag     [out]   Pointer to imaginary part of frequency domain
+//                              array
+// freq_signal_abs      [out]   Pointer to absolute value of frequency domain
+//                              array
+// freq_signal_sum_abs  [out]   Pointer to the sum of all absolute values in
+//                              the frequency domain array
+// return value                 The Q-domain of current frequency values
+//
+static int TimeToFrequencyDomain(AecmCore* aecm,
+                                 const int16_t* time_signal,
+                                 ComplexInt16* freq_signal,
+                                 uint16_t* freq_signal_abs,
+                                 uint32_t* freq_signal_sum_abs) {
+  int i = 0;
+  int time_signal_scaling = 0;
+
+  int32_t tmp32no1 = 0;
+  int32_t tmp32no2 = 0;
+
+  // In fft_buf, +16 for 32-byte alignment.
+  int16_t fft_buf[PART_LEN4 + 16];
+  int16_t* fft = (int16_t*)(((uintptr_t)fft_buf + 31) & ~31);
+
+  int16_t tmp16no1;
+#ifndef WEBRTC_ARCH_ARM_V7
+  int16_t tmp16no2;
+#endif
+#ifdef AECM_WITH_ABS_APPROX
+  int16_t max_value = 0;
+  int16_t min_value = 0;
+  uint16_t alpha = 0;
+  uint16_t beta = 0;
+#endif
+
+#ifdef AECM_DYNAMIC_Q
+  tmp16no1 = WebRtcSpl_MaxAbsValueW16(time_signal, PART_LEN2);
+  time_signal_scaling = WebRtcSpl_NormW16(tmp16no1);
+#endif
+
+  WindowAndFFT(aecm, fft, time_signal, freq_signal, time_signal_scaling);
+
+  // Extract imaginary and real part, calculate the magnitude for
+  // all frequency bins
+  freq_signal[0].imag = 0;
+  freq_signal[PART_LEN].imag = 0;
+  freq_signal_abs[0] = (uint16_t)WEBRTC_SPL_ABS_W16(freq_signal[0].real);
+  freq_signal_abs[PART_LEN] =
+      (uint16_t)WEBRTC_SPL_ABS_W16(freq_signal[PART_LEN].real);
+  (*freq_signal_sum_abs) =
+      (uint32_t)(freq_signal_abs[0]) + (uint32_t)(freq_signal_abs[PART_LEN]);
+
+  for (i = 1; i < PART_LEN; i++) {
+    if (freq_signal[i].real == 0) {
+      freq_signal_abs[i] = (uint16_t)WEBRTC_SPL_ABS_W16(freq_signal[i].imag);
+    } else if (freq_signal[i].imag == 0) {
+      freq_signal_abs[i] = (uint16_t)WEBRTC_SPL_ABS_W16(freq_signal[i].real);
+    } else {
+      // Approximation for magnitude of complex fft output
+      // magn = sqrt(real^2 + imag^2)
+      // magn ~= alpha * max(`imag`,`real`) + beta * min(`imag`,`real`)
+      //
+      // The parameters alpha and beta are stored in Q15
+
+#ifdef AECM_WITH_ABS_APPROX
+      tmp16no1 = WEBRTC_SPL_ABS_W16(freq_signal[i].real);
+      tmp16no2 = WEBRTC_SPL_ABS_W16(freq_signal[i].imag);
+
+      if (tmp16no1 > tmp16no2) {
+        max_value = tmp16no1;
+        min_value = tmp16no2;
+      } else {
+        max_value = tmp16no2;
+        min_value = tmp16no1;
+      }
+
+      // Magnitude in Q(-6)
+      if ((max_value >> 2) > min_value) {
+        alpha = kAlpha1;
+        beta = kBeta1;
+      } else if ((max_value >> 1) > min_value) {
+        alpha = kAlpha2;
+        beta = kBeta2;
+      } else {
+        alpha = kAlpha3;
+        beta = kBeta3;
+      }
+      tmp16no1 = (int16_t)((max_value * alpha) >> 15);
+      tmp16no2 = (int16_t)((min_value * beta) >> 15);
+      freq_signal_abs[i] = (uint16_t)tmp16no1 + (uint16_t)tmp16no2;
+#else
+#ifdef WEBRTC_ARCH_ARM_V7
+      __asm __volatile(
+          "smulbb %[tmp32no1], %[real], %[real]\n\t"
+          "smlabb %[tmp32no2], %[imag], %[imag], %[tmp32no1]\n\t"
+          : [tmp32no1] "+&r"(tmp32no1), [tmp32no2] "=r"(tmp32no2)
+          : [real] "r"(freq_signal[i].real), [imag] "r"(freq_signal[i].imag));
+#else
+      tmp16no1 = WEBRTC_SPL_ABS_W16(freq_signal[i].real);
+      tmp16no2 = WEBRTC_SPL_ABS_W16(freq_signal[i].imag);
+      tmp32no1 = tmp16no1 * tmp16no1;
+      tmp32no2 = tmp16no2 * tmp16no2;
+      tmp32no2 = WebRtcSpl_AddSatW32(tmp32no1, tmp32no2);
+#endif  // WEBRTC_ARCH_ARM_V7
+      tmp32no1 = WebRtcSpl_SqrtFloor(tmp32no2);
+
+      freq_signal_abs[i] = (uint16_t)tmp32no1;
+#endif  // AECM_WITH_ABS_APPROX
+    }
+    (*freq_signal_sum_abs) += (uint32_t)freq_signal_abs[i];
+  }
+
+  return time_signal_scaling;
+}
+
+}  // namespace
+
+int RTC_NO_SANITIZE("signed-integer-overflow")  // bugs.webrtc.org/8200
+    WebRtcAecm_ProcessBlock(AecmCore* aecm,
+                            const int16_t* farend,
+                            const int16_t* nearendNoisy,
+                            const int16_t* nearendClean,
+                            int16_t* output) {
+  int i;
+
+  uint32_t xfaSum;
+  uint32_t dfaNoisySum;
+  uint32_t dfaCleanSum;
+  uint32_t echoEst32Gained;
+  uint32_t tmpU32;
+
+  int32_t tmp32no1;
+
+  uint16_t xfa[PART_LEN1];
+  uint16_t dfaNoisy[PART_LEN1];
+  uint16_t dfaClean[PART_LEN1];
+  uint16_t* ptrDfaClean = dfaClean;
+  const uint16_t* far_spectrum_ptr = NULL;
+
+  // 32 byte aligned buffers (with +8 or +16).
+  // TODO(kma): define fft with ComplexInt16.
+  int16_t fft_buf[PART_LEN4 + 2 + 16];  // +2 to make a loop safe.
+  int32_t echoEst32_buf[PART_LEN1 + 8];
+  int32_t dfw_buf[PART_LEN2 + 8];
+  int32_t efw_buf[PART_LEN2 + 8];
+
+  int16_t* fft = (int16_t*)(((uintptr_t)fft_buf + 31) & ~31);
+  int32_t* echoEst32 = (int32_t*)(((uintptr_t)echoEst32_buf + 31) & ~31);
+  ComplexInt16* dfw = (ComplexInt16*)(((uintptr_t)dfw_buf + 31) & ~31);
+  ComplexInt16* efw = (ComplexInt16*)(((uintptr_t)efw_buf + 31) & ~31);
+
+  int16_t hnl[PART_LEN1];
+  int16_t numPosCoef = 0;
+  int16_t nlpGain = ONE_Q14;
+  int delay;
+  int16_t tmp16no1;
+  int16_t tmp16no2;
+  int16_t mu;
+  int16_t supGain;
+  int16_t zeros32, zeros16;
+  int16_t zerosDBufNoisy, zerosDBufClean, zerosXBuf;
+  int far_q;
+  int16_t resolutionDiff, qDomainDiff, dfa_clean_q_domain_diff;
+
+  const int kMinPrefBand = 4;
+  const int kMaxPrefBand = 24;
+  int32_t avgHnl32 = 0;
+
+  // Determine startup state. There are three states:
+  // (0) the first CONV_LEN blocks
+  // (1) another CONV_LEN blocks
+  // (2) the rest
+
+  if (aecm->startupState < 2) {
+    aecm->startupState =
+        (aecm->totCount >= CONV_LEN) + (aecm->totCount >= CONV_LEN2);
+  }
+  // END: Determine startup state
+
+  // Buffer near and far end signals
+  memcpy(aecm->xBuf + PART_LEN, farend, sizeof(int16_t) * PART_LEN);
+  memcpy(aecm->dBufNoisy + PART_LEN, nearendNoisy, sizeof(int16_t) * PART_LEN);
+  if (nearendClean != NULL) {
+    memcpy(aecm->dBufClean + PART_LEN, nearendClean,
+           sizeof(int16_t) * PART_LEN);
+  }
+
+  // Transform far end signal from time domain to frequency domain.
+  far_q = TimeToFrequencyDomain(aecm, aecm->xBuf, dfw, xfa, &xfaSum);
+
+  // Transform noisy near end signal from time domain to frequency domain.
+  zerosDBufNoisy =
+      TimeToFrequencyDomain(aecm, aecm->dBufNoisy, dfw, dfaNoisy, &dfaNoisySum);
+  aecm->dfaNoisyQDomainOld = aecm->dfaNoisyQDomain;
+  aecm->dfaNoisyQDomain = (int16_t)zerosDBufNoisy;
+
+  if (nearendClean == NULL) {
+    ptrDfaClean = dfaNoisy;
+    aecm->dfaCleanQDomainOld = aecm->dfaNoisyQDomainOld;
+    aecm->dfaCleanQDomain = aecm->dfaNoisyQDomain;
+    dfaCleanSum = dfaNoisySum;
+  } else {
+    // Transform clean near end signal from time domain to frequency domain.
+    zerosDBufClean = TimeToFrequencyDomain(aecm, aecm->dBufClean, dfw, dfaClean,
+                                           &dfaCleanSum);
+    aecm->dfaCleanQDomainOld = aecm->dfaCleanQDomain;
+    aecm->dfaCleanQDomain = (int16_t)zerosDBufClean;
+  }
+
+  // Get the delay
+  // Save far-end history and estimate delay
+  WebRtcAecm_UpdateFarHistory(aecm, xfa, far_q);
+  if (WebRtc_AddFarSpectrumFix(aecm->delay_estimator_farend, xfa, PART_LEN1,
+                               far_q) == -1) {
+    return -1;
+  }
+  delay = WebRtc_DelayEstimatorProcessFix(aecm->delay_estimator, dfaNoisy,
+                                          PART_LEN1, zerosDBufNoisy);
+  if (delay == -1) {
+    return -1;
+  } else if (delay == -2) {
+    // If the delay is unknown, we assume zero.
+    // NOTE: this will have to be adjusted if we ever add lookahead.
+    delay = 0;
+  }
+
+  if (aecm->fixedDelay >= 0) {
+    // Use fixed delay
+    delay = aecm->fixedDelay;
+  }
+
+  // Get aligned far end spectrum
+  far_spectrum_ptr = WebRtcAecm_AlignedFarend(aecm, &far_q, delay);
+  zerosXBuf = (int16_t)far_q;
+  if (far_spectrum_ptr == NULL) {
+    return -1;
+  }
+
+  // Calculate log(energy) and update energy threshold levels
+  WebRtcAecm_CalcEnergies(aecm, far_spectrum_ptr, zerosXBuf, dfaNoisySum,
+                          echoEst32);
+
+  // Calculate stepsize
+  mu = WebRtcAecm_CalcStepSize(aecm);
+
+  // Update counters
+  aecm->totCount++;
+
+  // This is the channel estimation algorithm.
+  // It is base on NLMS but has a variable step length,
+  // which was calculated above.
+  WebRtcAecm_UpdateChannel(aecm, far_spectrum_ptr, zerosXBuf, dfaNoisy, mu,
+                           echoEst32);
+  supGain = WebRtcAecm_CalcSuppressionGain(aecm);
+
+  // Calculate Wiener filter hnl[]
+  for (i = 0; i < PART_LEN1; i++) {
+    // Far end signal through channel estimate in Q8
+    // How much can we shift right to preserve resolution
+    tmp32no1 = echoEst32[i] - aecm->echoFilt[i];
+    aecm->echoFilt[i] +=
+        rtc::dchecked_cast<int32_t>((int64_t{tmp32no1} * 50) >> 8);
+
+    zeros32 = WebRtcSpl_NormW32(aecm->echoFilt[i]) + 1;
+    zeros16 = WebRtcSpl_NormW16(supGain) + 1;
+    if (zeros32 + zeros16 > 16) {
+      // Multiplication is safe
+      // Result in
+      // Q(RESOLUTION_CHANNEL+RESOLUTION_SUPGAIN+
+      //   aecm->xfaQDomainBuf[diff])
+      echoEst32Gained =
+          WEBRTC_SPL_UMUL_32_16((uint32_t)aecm->echoFilt[i], (uint16_t)supGain);
+      resolutionDiff = 14 - RESOLUTION_CHANNEL16 - RESOLUTION_SUPGAIN;
+      resolutionDiff += (aecm->dfaCleanQDomain - zerosXBuf);
+    } else {
+      tmp16no1 = 17 - zeros32 - zeros16;
+      resolutionDiff =
+          14 + tmp16no1 - RESOLUTION_CHANNEL16 - RESOLUTION_SUPGAIN;
+      resolutionDiff += (aecm->dfaCleanQDomain - zerosXBuf);
+      if (zeros32 > tmp16no1) {
+        echoEst32Gained = WEBRTC_SPL_UMUL_32_16((uint32_t)aecm->echoFilt[i],
+                                                supGain >> tmp16no1);
+      } else {
+        // Result in Q-(RESOLUTION_CHANNEL+RESOLUTION_SUPGAIN-16)
+        echoEst32Gained = (aecm->echoFilt[i] >> tmp16no1) * supGain;
+      }
+    }
+
+    zeros16 = WebRtcSpl_NormW16(aecm->nearFilt[i]);
+    RTC_DCHECK_GE(zeros16, 0);  // `zeros16` is a norm, hence non-negative.
+    dfa_clean_q_domain_diff = aecm->dfaCleanQDomain - aecm->dfaCleanQDomainOld;
+    if (zeros16 < dfa_clean_q_domain_diff && aecm->nearFilt[i]) {
+      tmp16no1 = aecm->nearFilt[i] * (1 << zeros16);
+      qDomainDiff = zeros16 - dfa_clean_q_domain_diff;
+      tmp16no2 = ptrDfaClean[i] >> -qDomainDiff;
+    } else {
+      tmp16no1 = dfa_clean_q_domain_diff < 0
+                     ? aecm->nearFilt[i] >> -dfa_clean_q_domain_diff
+                     : aecm->nearFilt[i] * (1 << dfa_clean_q_domain_diff);
+      qDomainDiff = 0;
+      tmp16no2 = ptrDfaClean[i];
+    }
+    tmp32no1 = (int32_t)(tmp16no2 - tmp16no1);
+    tmp16no2 = (int16_t)(tmp32no1 >> 4);
+    tmp16no2 += tmp16no1;
+    zeros16 = WebRtcSpl_NormW16(tmp16no2);
+    if ((tmp16no2) & (-qDomainDiff > zeros16)) {
+      aecm->nearFilt[i] = WEBRTC_SPL_WORD16_MAX;
+    } else {
+      aecm->nearFilt[i] = qDomainDiff < 0 ? tmp16no2 * (1 << -qDomainDiff)
+                                          : tmp16no2 >> qDomainDiff;
+    }
+
+    // Wiener filter coefficients, resulting hnl in Q14
+    if (echoEst32Gained == 0) {
+      hnl[i] = ONE_Q14;
+    } else if (aecm->nearFilt[i] == 0) {
+      hnl[i] = 0;
+    } else {
+      // Multiply the suppression gain
+      // Rounding
+      echoEst32Gained += (uint32_t)(aecm->nearFilt[i] >> 1);
+      tmpU32 =
+          WebRtcSpl_DivU32U16(echoEst32Gained, (uint16_t)aecm->nearFilt[i]);
+
+      // Current resolution is
+      // Q-(RESOLUTION_CHANNEL+RESOLUTION_SUPGAIN- max(0,17-zeros16- zeros32))
+      // Make sure we are in Q14
+      tmp32no1 = (int32_t)WEBRTC_SPL_SHIFT_W32(tmpU32, resolutionDiff);
+      if (tmp32no1 > ONE_Q14) {
+        hnl[i] = 0;
+      } else if (tmp32no1 < 0) {
+        hnl[i] = ONE_Q14;
+      } else {
+        // 1-echoEst/dfa
+        hnl[i] = ONE_Q14 - (int16_t)tmp32no1;
+        if (hnl[i] < 0) {
+          hnl[i] = 0;
+        }
+      }
+    }
+    if (hnl[i]) {
+      numPosCoef++;
+    }
+  }
+  // Only in wideband. Prevent the gain in upper band from being larger than
+  // in lower band.
+  if (aecm->mult == 2) {
+    // TODO(bjornv): Investigate if the scaling of hnl[i] below can cause
+    //               speech distortion in double-talk.
+    for (i = 0; i < PART_LEN1; i++) {
+      hnl[i] = (int16_t)((hnl[i] * hnl[i]) >> 14);
+    }
+
+    for (i = kMinPrefBand; i <= kMaxPrefBand; i++) {
+      avgHnl32 += (int32_t)hnl[i];
+    }
+    RTC_DCHECK_GT(kMaxPrefBand - kMinPrefBand + 1, 0);
+    avgHnl32 /= (kMaxPrefBand - kMinPrefBand + 1);
+
+    for (i = kMaxPrefBand; i < PART_LEN1; i++) {
+      if (hnl[i] > (int16_t)avgHnl32) {
+        hnl[i] = (int16_t)avgHnl32;
+      }
+    }
+  }
+
+  // Calculate NLP gain, result is in Q14
+  if (aecm->nlpFlag) {
+    for (i = 0; i < PART_LEN1; i++) {
+      // Truncate values close to zero and one.
+      if (hnl[i] > NLP_COMP_HIGH) {
+        hnl[i] = ONE_Q14;
+      } else if (hnl[i] < NLP_COMP_LOW) {
+        hnl[i] = 0;
+      }
+
+      // Remove outliers
+      if (numPosCoef < 3) {
+        nlpGain = 0;
+      } else {
+        nlpGain = ONE_Q14;
+      }
+
+      // NLP
+      if ((hnl[i] == ONE_Q14) && (nlpGain == ONE_Q14)) {
+        hnl[i] = ONE_Q14;
+      } else {
+        hnl[i] = (int16_t)((hnl[i] * nlpGain) >> 14);
+      }
+
+      // multiply with Wiener coefficients
+      efw[i].real = (int16_t)(WEBRTC_SPL_MUL_16_16_RSFT_WITH_ROUND(dfw[i].real,
+                                                                   hnl[i], 14));
+      efw[i].imag = (int16_t)(WEBRTC_SPL_MUL_16_16_RSFT_WITH_ROUND(dfw[i].imag,
+                                                                   hnl[i], 14));
+    }
+  } else {
+    // multiply with Wiener coefficients
+    for (i = 0; i < PART_LEN1; i++) {
+      efw[i].real = (int16_t)(WEBRTC_SPL_MUL_16_16_RSFT_WITH_ROUND(dfw[i].real,
+                                                                   hnl[i], 14));
+      efw[i].imag = (int16_t)(WEBRTC_SPL_MUL_16_16_RSFT_WITH_ROUND(dfw[i].imag,
+                                                                   hnl[i], 14));
+    }
+  }
+
+  if (aecm->cngMode == AecmTrue) {
+    ComfortNoise(aecm, ptrDfaClean, efw, hnl);
+  }
+
+  InverseFFTAndWindow(aecm, fft, efw, output, nearendClean);
+
+  return 0;
+}
+
+}  // namespace webrtc

VocieProcess/modules/audio_processing/aecm/aecm_core_neon.cc

@@ -0,0 +1,206 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include <arm_neon.h>
+
+#include "common_audio/signal_processing/include/real_fft.h"
+#include "modules/audio_processing/aecm/aecm_core.h"
+#include "rtc_base/checks.h"
+
+namespace webrtc {
+
+namespace {
+
+// TODO(kma): Re-write the corresponding assembly file, the offset
+// generating script and makefile, to replace these C functions.
+
+static inline void AddLanes(uint32_t* ptr, uint32x4_t v) {
+#if defined(WEBRTC_ARCH_ARM64)
+  *(ptr) = vaddvq_u32(v);
+#else
+  uint32x2_t tmp_v;
+  tmp_v = vadd_u32(vget_low_u32(v), vget_high_u32(v));
+  tmp_v = vpadd_u32(tmp_v, tmp_v);
+  *(ptr) = vget_lane_u32(tmp_v, 0);
+#endif
+}
+
+}  // namespace
+
+void WebRtcAecm_CalcLinearEnergiesNeon(AecmCore* aecm,
+                                       const uint16_t* far_spectrum,
+                                       int32_t* echo_est,
+                                       uint32_t* far_energy,
+                                       uint32_t* echo_energy_adapt,
+                                       uint32_t* echo_energy_stored) {
+  int16_t* start_stored_p = aecm->channelStored;
+  int16_t* start_adapt_p = aecm->channelAdapt16;
+  int32_t* echo_est_p = echo_est;
+  const int16_t* end_stored_p = aecm->channelStored + PART_LEN;
+  const uint16_t* far_spectrum_p = far_spectrum;
+  int16x8_t store_v, adapt_v;
+  uint16x8_t spectrum_v;
+  uint32x4_t echo_est_v_low, echo_est_v_high;
+  uint32x4_t far_energy_v, echo_stored_v, echo_adapt_v;
+
+  far_energy_v = vdupq_n_u32(0);
+  echo_adapt_v = vdupq_n_u32(0);
+  echo_stored_v = vdupq_n_u32(0);
+
+  // Get energy for the delayed far end signal and estimated
+  // echo using both stored and adapted channels.
+  // The C code:
+  //  for (i = 0; i < PART_LEN1; i++) {
+  //      echo_est[i] = WEBRTC_SPL_MUL_16_U16(aecm->channelStored[i],
+  //                                         far_spectrum[i]);
+  //      (*far_energy) += (uint32_t)(far_spectrum[i]);
+  //      *echo_energy_adapt += aecm->channelAdapt16[i] * far_spectrum[i];
+  //      (*echo_energy_stored) += (uint32_t)echo_est[i];
+  //  }
+  while (start_stored_p < end_stored_p) {
+    spectrum_v = vld1q_u16(far_spectrum_p);
+    adapt_v = vld1q_s16(start_adapt_p);
+    store_v = vld1q_s16(start_stored_p);
+
+    far_energy_v = vaddw_u16(far_energy_v, vget_low_u16(spectrum_v));
+    far_energy_v = vaddw_u16(far_energy_v, vget_high_u16(spectrum_v));
+
+    echo_est_v_low = vmull_u16(vreinterpret_u16_s16(vget_low_s16(store_v)),
+                               vget_low_u16(spectrum_v));
+    echo_est_v_high = vmull_u16(vreinterpret_u16_s16(vget_high_s16(store_v)),
+                                vget_high_u16(spectrum_v));
+    vst1q_s32(echo_est_p, vreinterpretq_s32_u32(echo_est_v_low));
+    vst1q_s32(echo_est_p + 4, vreinterpretq_s32_u32(echo_est_v_high));
+
+    echo_stored_v = vaddq_u32(echo_est_v_low, echo_stored_v);
+    echo_stored_v = vaddq_u32(echo_est_v_high, echo_stored_v);
+
+    echo_adapt_v =
+        vmlal_u16(echo_adapt_v, vreinterpret_u16_s16(vget_low_s16(adapt_v)),
+                  vget_low_u16(spectrum_v));
+    echo_adapt_v =
+        vmlal_u16(echo_adapt_v, vreinterpret_u16_s16(vget_high_s16(adapt_v)),
+                  vget_high_u16(spectrum_v));
+
+    start_stored_p += 8;
+    start_adapt_p += 8;
+    far_spectrum_p += 8;
+    echo_est_p += 8;
+  }
+
+  AddLanes(far_energy, far_energy_v);
+  AddLanes(echo_energy_stored, echo_stored_v);
+  AddLanes(echo_energy_adapt, echo_adapt_v);
+
+  echo_est[PART_LEN] = WEBRTC_SPL_MUL_16_U16(aecm->channelStored[PART_LEN],
+                                             far_spectrum[PART_LEN]);
+  *echo_energy_stored += (uint32_t)echo_est[PART_LEN];
+  *far_energy += (uint32_t)far_spectrum[PART_LEN];
+  *echo_energy_adapt += aecm->channelAdapt16[PART_LEN] * far_spectrum[PART_LEN];
+}
+
+void WebRtcAecm_StoreAdaptiveChannelNeon(AecmCore* aecm,
+                                         const uint16_t* far_spectrum,
+                                         int32_t* echo_est) {
+  RTC_DCHECK_EQ(0, (uintptr_t)echo_est % 32);
+  RTC_DCHECK_EQ(0, (uintptr_t)aecm->channelStored % 16);
+  RTC_DCHECK_EQ(0, (uintptr_t)aecm->channelAdapt16 % 16);
+
+  // This is C code of following optimized code.
+  // During startup we store the channel every block.
+  //  memcpy(aecm->channelStored,
+  //         aecm->channelAdapt16,
+  //         sizeof(int16_t) * PART_LEN1);
+  // Recalculate echo estimate
+  //  for (i = 0; i < PART_LEN; i += 4) {
+  //    echo_est[i] = WEBRTC_SPL_MUL_16_U16(aecm->channelStored[i],
+  //                                        far_spectrum[i]);
+  //    echo_est[i + 1] = WEBRTC_SPL_MUL_16_U16(aecm->channelStored[i + 1],
+  //                                            far_spectrum[i + 1]);
+  //    echo_est[i + 2] = WEBRTC_SPL_MUL_16_U16(aecm->channelStored[i + 2],
+  //                                            far_spectrum[i + 2]);
+  //    echo_est[i + 3] = WEBRTC_SPL_MUL_16_U16(aecm->channelStored[i + 3],
+  //                                            far_spectrum[i + 3]);
+  //  }
+  //  echo_est[i] = WEBRTC_SPL_MUL_16_U16(aecm->channelStored[i],
+  //                                     far_spectrum[i]);
+  const uint16_t* far_spectrum_p = far_spectrum;
+  int16_t* start_adapt_p = aecm->channelAdapt16;
+  int16_t* start_stored_p = aecm->channelStored;
+  const int16_t* end_stored_p = aecm->channelStored + PART_LEN;
+  int32_t* echo_est_p = echo_est;
+
+  uint16x8_t far_spectrum_v;
+  int16x8_t adapt_v;
+  uint32x4_t echo_est_v_low, echo_est_v_high;
+
+  while (start_stored_p < end_stored_p) {
+    far_spectrum_v = vld1q_u16(far_spectrum_p);
+    adapt_v = vld1q_s16(start_adapt_p);
+
+    vst1q_s16(start_stored_p, adapt_v);
+
+    echo_est_v_low = vmull_u16(vget_low_u16(far_spectrum_v),
+                               vget_low_u16(vreinterpretq_u16_s16(adapt_v)));
+    echo_est_v_high = vmull_u16(vget_high_u16(far_spectrum_v),
+                                vget_high_u16(vreinterpretq_u16_s16(adapt_v)));
+
+    vst1q_s32(echo_est_p, vreinterpretq_s32_u32(echo_est_v_low));
+    vst1q_s32(echo_est_p + 4, vreinterpretq_s32_u32(echo_est_v_high));
+
+    far_spectrum_p += 8;
+    start_adapt_p += 8;
+    start_stored_p += 8;
+    echo_est_p += 8;
+  }
+  aecm->channelStored[PART_LEN] = aecm->channelAdapt16[PART_LEN];
+  echo_est[PART_LEN] = WEBRTC_SPL_MUL_16_U16(aecm->channelStored[PART_LEN],
+                                             far_spectrum[PART_LEN]);
+}
+
+void WebRtcAecm_ResetAdaptiveChannelNeon(AecmCore* aecm) {
+  RTC_DCHECK_EQ(0, (uintptr_t)aecm->channelStored % 16);
+  RTC_DCHECK_EQ(0, (uintptr_t)aecm->channelAdapt16 % 16);
+  RTC_DCHECK_EQ(0, (uintptr_t)aecm->channelAdapt32 % 32);
+
+  // The C code of following optimized code.
+  // for (i = 0; i < PART_LEN1; i++) {
+  //   aecm->channelAdapt16[i] = aecm->channelStored[i];
+  //   aecm->channelAdapt32[i] = WEBRTC_SPL_LSHIFT_W32(
+  //              (int32_t)aecm->channelStored[i], 16);
+  // }
+
+  int16_t* start_stored_p = aecm->channelStored;
+  int16_t* start_adapt16_p = aecm->channelAdapt16;
+  int32_t* start_adapt32_p = aecm->channelAdapt32;
+  const int16_t* end_stored_p = start_stored_p + PART_LEN;
+
+  int16x8_t stored_v;
+  int32x4_t adapt32_v_low, adapt32_v_high;
+
+  while (start_stored_p < end_stored_p) {
+    stored_v = vld1q_s16(start_stored_p);
+    vst1q_s16(start_adapt16_p, stored_v);
+
+    adapt32_v_low = vshll_n_s16(vget_low_s16(stored_v), 16);
+    adapt32_v_high = vshll_n_s16(vget_high_s16(stored_v), 16);
+
+    vst1q_s32(start_adapt32_p, adapt32_v_low);
+    vst1q_s32(start_adapt32_p + 4, adapt32_v_high);
+
+    start_stored_p += 8;
+    start_adapt16_p += 8;
+    start_adapt32_p += 8;
+  }
+  aecm->channelAdapt16[PART_LEN] = aecm->channelStored[PART_LEN];
+  aecm->channelAdapt32[PART_LEN] = (int32_t)aecm->channelStored[PART_LEN] << 16;
+}
+
+}  // namespace webrtc

VocieProcess/modules/audio_processing/aecm/aecm_defines.h

@@ -0,0 +1,87 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef MODULES_AUDIO_PROCESSING_AECM_AECM_DEFINES_H_
+#define MODULES_AUDIO_PROCESSING_AECM_AECM_DEFINES_H_
+
+#define AECM_DYNAMIC_Q /* Turn on/off dynamic Q-domain. */
+
+/* Algorithm parameters */
+#define FRAME_LEN 80 /* Total frame length, 10 ms. */
+
+#define PART_LEN 64      /* Length of partition. */
+#define PART_LEN_SHIFT 7 /* Length of (PART_LEN * 2) in base 2. */
+
+#define PART_LEN1 (PART_LEN + 1)  /* Unique fft coefficients. */
+#define PART_LEN2 (PART_LEN << 1) /* Length of partition * 2. */
+#define PART_LEN4 (PART_LEN << 2) /* Length of partition * 4. */
+#define FAR_BUF_LEN PART_LEN4     /* Length of buffers. */
+#define MAX_DELAY 100
+
+/* Counter parameters */
+#define CONV_LEN 512              /* Convergence length used at startup. */
+#define CONV_LEN2 (CONV_LEN << 1) /* Used at startup. */
+
+/* Energy parameters */
+#define MAX_BUF_LEN 64            /* History length of energy signals. */
+#define FAR_ENERGY_MIN 1025       /* Lowest Far energy level: At least 2 */
+                                  /* in energy. */
+#define FAR_ENERGY_DIFF 929       /* Allowed difference between max */
+                                  /* and min. */
+#define ENERGY_DEV_OFFSET 0       /* The energy error offset in Q8. */
+#define ENERGY_DEV_TOL 400        /* The energy estimation tolerance (Q8). */
+#define FAR_ENERGY_VAD_REGION 230 /* Far VAD tolerance region. */
+
+/* Stepsize parameters */
+#define MU_MIN 10 /* Min stepsize 2^-MU_MIN (far end energy */
+                  /* dependent). */
+#define MU_MAX 1  /* Max stepsize 2^-MU_MAX (far end energy */
+                  /* dependent). */
+#define MU_DIFF 9 /* MU_MIN - MU_MAX */
+
+/* Channel parameters */
+#define MIN_MSE_COUNT 20 /* Min number of consecutive blocks with enough */
+                         /* far end energy to compare channel estimates. */
+#define MIN_MSE_DIFF 29  /* The ratio between adapted and stored channel to */
+                         /* accept a new storage (0.8 in Q-MSE_RESOLUTION). */
+#define MSE_RESOLUTION 5 /* MSE parameter resolution. */
+#define RESOLUTION_CHANNEL16 12 /* W16 Channel in Q-RESOLUTION_CHANNEL16. */
+#define RESOLUTION_CHANNEL32 28 /* W32 Channel in Q-RESOLUTION_CHANNEL. */
+#define CHANNEL_VAD 16          /* Minimum energy in frequency band */
+                                /* to update channel. */
+
+/* Suppression gain parameters: SUPGAIN parameters in Q-(RESOLUTION_SUPGAIN). */
+#define RESOLUTION_SUPGAIN 8 /* Channel in Q-(RESOLUTION_SUPGAIN). */
+#define SUPGAIN_DEFAULT (1 << RESOLUTION_SUPGAIN) /* Default. */
+#define SUPGAIN_ERROR_PARAM_A 3072            /* Estimation error parameter */
+                                              /* (Maximum gain) (8 in Q8). */
+#define SUPGAIN_ERROR_PARAM_B 1536            /* Estimation error parameter */
+                                              /* (Gain before going down). */
+#define SUPGAIN_ERROR_PARAM_D SUPGAIN_DEFAULT /* Estimation error parameter */
+/* (Should be the same as Default) (1 in Q8). */
+#define SUPGAIN_EPC_DT 200 /* SUPGAIN_ERROR_PARAM_C * ENERGY_DEV_TOL */
+
+/* Defines for "check delay estimation" */
+#define CORR_WIDTH 31 /* Number of samples to correlate over. */
+#define CORR_MAX 16   /* Maximum correlation offset. */
+#define CORR_MAX_BUF 63
+#define CORR_DEV 4
+#define CORR_MAX_LEVEL 20
+#define CORR_MAX_LOW 4
+#define CORR_BUF_LEN (CORR_MAX << 1) + 1
+/* Note that CORR_WIDTH + 2*CORR_MAX <= MAX_BUF_LEN. */
+
+#define ONE_Q14 (1 << 14)
+
+/* NLP defines */
+#define NLP_COMP_LOW 3277     /* 0.2 in Q14 */
+#define NLP_COMP_HIGH ONE_Q14 /* 1 in Q14 */
+
+#endif

VocieProcess/modules/audio_processing/aecm/echo_control_mobile.cc

@@ -0,0 +1,599 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "modules/audio_processing/aecm/echo_control_mobile.h"
+
+#ifdef AEC_DEBUG
+#include <stdio.h>
+#endif
+#include <stdlib.h>
+#include <string.h>
+
+extern "C" {
+#include "common_audio/ring_buffer.h"
+#include "common_audio/signal_processing/include/signal_processing_library.h"
+#include "modules/audio_processing/aecm/aecm_defines.h"
+}
+#include "modules/audio_processing/aecm/aecm_core.h"
+
+namespace webrtc {
+
+namespace {
+
+#define BUF_SIZE_FRAMES 50  // buffer size (frames)
+// Maximum length of resampled signal. Must be an integer multiple of frames
+// (ceil(1/(1 + MIN_SKEW)*2) + 1)*FRAME_LEN
+// The factor of 2 handles wb, and the + 1 is as a safety margin
+#define MAX_RESAMP_LEN (5 * FRAME_LEN)
+
+static const size_t kBufSizeSamp =
+    BUF_SIZE_FRAMES * FRAME_LEN;  // buffer size (samples)
+static const int kSampMsNb = 8;   // samples per ms in nb
+// Target suppression levels for nlp modes
+// log{0.001, 0.00001, 0.00000001}
+static const int kInitCheck = 42;
+
+typedef struct {
+  int sampFreq;
+  int scSampFreq;
+  short bufSizeStart;
+  int knownDelay;
+
+  // Stores the last frame added to the farend buffer
+  short farendOld[2][FRAME_LEN];
+  short initFlag;  // indicates if AEC has been initialized
+
+  // Variables used for averaging far end buffer size
+  short counter;
+  short sum;
+  short firstVal;
+  short checkBufSizeCtr;
+
+  // Variables used for delay shifts
+  short msInSndCardBuf;
+  short filtDelay;
+  int timeForDelayChange;
+  int ECstartup;
+  int checkBuffSize;
+  int delayChange;
+  short lastDelayDiff;
+
+  int16_t echoMode;
+
+#ifdef AEC_DEBUG
+  FILE* bufFile;
+  FILE* delayFile;
+  FILE* preCompFile;
+  FILE* postCompFile;
+#endif  // AEC_DEBUG
+  // Structures
+  RingBuffer* farendBuf;
+
+  AecmCore* aecmCore;
+} AecMobile;
+
+}  // namespace
+
+// Estimates delay to set the position of the farend buffer read pointer
+// (controlled by knownDelay)
+static int WebRtcAecm_EstBufDelay(AecMobile* aecm, short msInSndCardBuf);
+
+// Stuffs the farend buffer if the estimated delay is too large
+static int WebRtcAecm_DelayComp(AecMobile* aecm);
+
+void* WebRtcAecm_Create() {
+  // Allocate zero-filled memory.
+  AecMobile* aecm = static_cast<AecMobile*>(calloc(1, sizeof(AecMobile)));
+
+  aecm->aecmCore = WebRtcAecm_CreateCore();
+  if (!aecm->aecmCore) {
+    WebRtcAecm_Free(aecm);
+    return NULL;
+  }
+
+  aecm->farendBuf = WebRtc_CreateBuffer(kBufSizeSamp, sizeof(int16_t));
+  if (!aecm->farendBuf) {
+    WebRtcAecm_Free(aecm);
+    return NULL;
+  }
+
+#ifdef AEC_DEBUG
+  aecm->aecmCore->farFile = fopen("aecFar.pcm", "wb");
+  aecm->aecmCore->nearFile = fopen("aecNear.pcm", "wb");
+  aecm->aecmCore->outFile = fopen("aecOut.pcm", "wb");
+  // aecm->aecmCore->outLpFile = fopen("aecOutLp.pcm","wb");
+
+  aecm->bufFile = fopen("aecBuf.dat", "wb");
+  aecm->delayFile = fopen("aecDelay.dat", "wb");
+  aecm->preCompFile = fopen("preComp.pcm", "wb");
+  aecm->postCompFile = fopen("postComp.pcm", "wb");
+#endif  // AEC_DEBUG
+  return aecm;
+}
+
+void WebRtcAecm_Free(void* aecmInst) {
+  AecMobile* aecm = static_cast<AecMobile*>(aecmInst);
+
+  if (aecm == NULL) {
+    return;
+  }
+
+#ifdef AEC_DEBUG
+  fclose(aecm->aecmCore->farFile);
+  fclose(aecm->aecmCore->nearFile);
+  fclose(aecm->aecmCore->outFile);
+  // fclose(aecm->aecmCore->outLpFile);
+
+  fclose(aecm->bufFile);
+  fclose(aecm->delayFile);
+  fclose(aecm->preCompFile);
+  fclose(aecm->postCompFile);
+#endif  // AEC_DEBUG
+  WebRtcAecm_FreeCore(aecm->aecmCore);
+  WebRtc_FreeBuffer(aecm->farendBuf);
+  free(aecm);
+}
+
+int32_t WebRtcAecm_Init(void* aecmInst, int32_t sampFreq) {
+  AecMobile* aecm = static_cast<AecMobile*>(aecmInst);
+  AecmConfig aecConfig;
+
+  if (aecm == NULL) {
+    return -1;
+  }
+
+  if (sampFreq != 8000 && sampFreq != 16000) {
+    return AECM_BAD_PARAMETER_ERROR;
+  }
+  aecm->sampFreq = sampFreq;
+
+  // Initialize AECM core
+  if (WebRtcAecm_InitCore(aecm->aecmCore, aecm->sampFreq) == -1) {
+    return AECM_UNSPECIFIED_ERROR;
+  }
+
+  // Initialize farend buffer
+  WebRtc_InitBuffer(aecm->farendBuf);
+
+  aecm->initFlag = kInitCheck;  // indicates that initialization has been done
+
+  aecm->delayChange = 1;
+
+  aecm->sum = 0;
+  aecm->counter = 0;
+  aecm->checkBuffSize = 1;
+  aecm->firstVal = 0;
+
+  aecm->ECstartup = 1;
+  aecm->bufSizeStart = 0;
+  aecm->checkBufSizeCtr = 0;
+  aecm->filtDelay = 0;
+  aecm->timeForDelayChange = 0;
+  aecm->knownDelay = 0;
+  aecm->lastDelayDiff = 0;
+
+  memset(&aecm->farendOld, 0, sizeof(aecm->farendOld));
+
+  // Default settings.
+  aecConfig.cngMode = AecmTrue;
+  aecConfig.echoMode = 3;
+
+  if (WebRtcAecm_set_config(aecm, aecConfig) == -1) {
+    return AECM_UNSPECIFIED_ERROR;
+  }
+
+  return 0;
+}
+
+// Returns any error that is caused when buffering the
+// farend signal.
+int32_t WebRtcAecm_GetBufferFarendError(void* aecmInst,
+                                        const int16_t* farend,
+                                        size_t nrOfSamples) {
+  AecMobile* aecm = static_cast<AecMobile*>(aecmInst);
+
+  if (aecm == NULL)
+    return -1;
+
+  if (farend == NULL)
+    return AECM_NULL_POINTER_ERROR;
+
+  if (aecm->initFlag != kInitCheck)
+    return AECM_UNINITIALIZED_ERROR;
+
+  if (nrOfSamples != 80 && nrOfSamples != 160)
+    return AECM_BAD_PARAMETER_ERROR;
+
+  return 0;
+}
+
+int32_t WebRtcAecm_BufferFarend(void* aecmInst,
+                                const int16_t* farend,
+                                size_t nrOfSamples) {
+  AecMobile* aecm = static_cast<AecMobile*>(aecmInst);
+
+  const int32_t err =
+      WebRtcAecm_GetBufferFarendError(aecmInst, farend, nrOfSamples);
+
+  if (err != 0)
+    return err;
+
+  // TODO(unknown): Is this really a good idea?
+  if (!aecm->ECstartup) {
+    WebRtcAecm_DelayComp(aecm);
+  }
+
+  WebRtc_WriteBuffer(aecm->farendBuf, farend, nrOfSamples);
+
+  return 0;
+}
+
+int32_t WebRtcAecm_Process(void* aecmInst,
+                           const int16_t* nearendNoisy,
+                           const int16_t* nearendClean,
+                           int16_t* out,
+                           size_t nrOfSamples,
+                           int16_t msInSndCardBuf) {
+  AecMobile* aecm = static_cast<AecMobile*>(aecmInst);
+  int32_t retVal = 0;
+  size_t i;
+  short nmbrOfFilledBuffers;
+  size_t nBlocks10ms;
+  size_t nFrames;
+#ifdef AEC_DEBUG
+  short msInAECBuf;
+#endif
+
+  if (aecm == NULL) {
+    return -1;
+  }
+
+  if (nearendNoisy == NULL) {
+    return AECM_NULL_POINTER_ERROR;
+  }
+
+  if (out == NULL) {
+    return AECM_NULL_POINTER_ERROR;
+  }
+
+  if (aecm->initFlag != kInitCheck) {
+    return AECM_UNINITIALIZED_ERROR;
+  }
+
+  if (nrOfSamples != 80 && nrOfSamples != 160) {
+    return AECM_BAD_PARAMETER_ERROR;
+  }
+
+  if (msInSndCardBuf < 0) {
+    msInSndCardBuf = 0;
+    retVal = AECM_BAD_PARAMETER_WARNING;
+  } else if (msInSndCardBuf > 500) {
+    msInSndCardBuf = 500;
+    retVal = AECM_BAD_PARAMETER_WARNING;
+  }
+  msInSndCardBuf += 10;
+  aecm->msInSndCardBuf = msInSndCardBuf;
+
+  nFrames = nrOfSamples / FRAME_LEN;
+  nBlocks10ms = nFrames / aecm->aecmCore->mult;
+
+  if (aecm->ECstartup) {
+    if (nearendClean == NULL) {
+      if (out != nearendNoisy) {
+        memcpy(out, nearendNoisy, sizeof(short) * nrOfSamples);
+      }
+    } else if (out != nearendClean) {
+      memcpy(out, nearendClean, sizeof(short) * nrOfSamples);
+    }
+
+    nmbrOfFilledBuffers =
+        (short)WebRtc_available_read(aecm->farendBuf) / FRAME_LEN;
+    // The AECM is in the start up mode
+    // AECM is disabled until the soundcard buffer and farend buffers are OK
+
+    // Mechanism to ensure that the soundcard buffer is reasonably stable.
+    if (aecm->checkBuffSize) {
+      aecm->checkBufSizeCtr++;
+      // Before we fill up the far end buffer we require the amount of data on
+      // the sound card to be stable (+/-8 ms) compared to the first value. This
+      // comparison is made during the following 4 consecutive frames. If it
+      // seems to be stable then we start to fill up the far end buffer.
+
+      if (aecm->counter == 0) {
+        aecm->firstVal = aecm->msInSndCardBuf;
+        aecm->sum = 0;
+      }
+
+      if (abs(aecm->firstVal - aecm->msInSndCardBuf) <
+          WEBRTC_SPL_MAX(0.2 * aecm->msInSndCardBuf, kSampMsNb)) {
+        aecm->sum += aecm->msInSndCardBuf;
+        aecm->counter++;
+      } else {
+        aecm->counter = 0;
+      }
+
+      if (aecm->counter * nBlocks10ms >= 6) {
+        // The farend buffer size is determined in blocks of 80 samples
+        // Use 75% of the average value of the soundcard buffer
+        aecm->bufSizeStart = WEBRTC_SPL_MIN(
+            (3 * aecm->sum * aecm->aecmCore->mult) / (aecm->counter * 40),
+            BUF_SIZE_FRAMES);
+        // buffersize has now been determined
+        aecm->checkBuffSize = 0;
+      }
+
+      if (aecm->checkBufSizeCtr * nBlocks10ms > 50) {
+        // for really bad sound cards, don't disable echocanceller for more than
+        // 0.5 sec
+        aecm->bufSizeStart = WEBRTC_SPL_MIN(
+            (3 * aecm->msInSndCardBuf * aecm->aecmCore->mult) / 40,
+            BUF_SIZE_FRAMES);
+        aecm->checkBuffSize = 0;
+      }
+    }
+
+    // if checkBuffSize changed in the if-statement above
+    if (!aecm->checkBuffSize) {
+      // soundcard buffer is now reasonably stable
+      // When the far end buffer is filled with approximately the same amount of
+      // data as the amount on the sound card we end the start up phase and
+      // start to cancel echoes.
+
+      if (nmbrOfFilledBuffers == aecm->bufSizeStart) {
+        aecm->ECstartup = 0;  // Enable the AECM
+      } else if (nmbrOfFilledBuffers > aecm->bufSizeStart) {
+        WebRtc_MoveReadPtr(aecm->farendBuf,
+                           (int)WebRtc_available_read(aecm->farendBuf) -
+                               (int)aecm->bufSizeStart * FRAME_LEN);
+        aecm->ECstartup = 0;
+      }
+    }
+
+  } else {
+    // AECM is enabled
+
+    // Note only 1 block supported for nb and 2 blocks for wb
+    for (i = 0; i < nFrames; i++) {
+      int16_t farend[FRAME_LEN];
+      const int16_t* farend_ptr = NULL;
+
+      nmbrOfFilledBuffers =
+          (short)WebRtc_available_read(aecm->farendBuf) / FRAME_LEN;
+
+      // Check that there is data in the far end buffer
+      if (nmbrOfFilledBuffers > 0) {
+        // Get the next 80 samples from the farend buffer
+        WebRtc_ReadBuffer(aecm->farendBuf, (void**)&farend_ptr, farend,
+                          FRAME_LEN);
+
+        // Always store the last frame for use when we run out of data
+        memcpy(&(aecm->farendOld[i][0]), farend_ptr, FRAME_LEN * sizeof(short));
+      } else {
+        // We have no data so we use the last played frame
+        memcpy(farend, &(aecm->farendOld[i][0]), FRAME_LEN * sizeof(short));
+        farend_ptr = farend;
+      }
+
+      // Call buffer delay estimator when all data is extracted,
+      // i,e. i = 0 for NB and i = 1 for WB
+      if ((i == 0 && aecm->sampFreq == 8000) ||
+          (i == 1 && aecm->sampFreq == 16000)) {
+        WebRtcAecm_EstBufDelay(aecm, aecm->msInSndCardBuf);
+      }
+
+      // Call the AECM
+      /*WebRtcAecm_ProcessFrame(aecm->aecmCore, farend, &nearend[FRAME_LEN * i],
+       &out[FRAME_LEN * i], aecm->knownDelay);*/
+      if (WebRtcAecm_ProcessFrame(
+              aecm->aecmCore, farend_ptr, &nearendNoisy[FRAME_LEN * i],
+              (nearendClean ? &nearendClean[FRAME_LEN * i] : NULL),
+              &out[FRAME_LEN * i]) == -1)
+        return -1;
+    }
+  }
+
+#ifdef AEC_DEBUG
+  msInAECBuf = (short)WebRtc_available_read(aecm->farendBuf) /
+               (kSampMsNb * aecm->aecmCore->mult);
+  fwrite(&msInAECBuf, 2, 1, aecm->bufFile);
+  fwrite(&(aecm->knownDelay), sizeof(aecm->knownDelay), 1, aecm->delayFile);
+#endif
+
+  return retVal;
+}
+
+int32_t WebRtcAecm_set_config(void* aecmInst, AecmConfig config) {
+  AecMobile* aecm = static_cast<AecMobile*>(aecmInst);
+
+  if (aecm == NULL) {
+    return -1;
+  }
+
+  if (aecm->initFlag != kInitCheck) {
+    return AECM_UNINITIALIZED_ERROR;
+  }
+
+  if (config.cngMode != AecmFalse && config.cngMode != AecmTrue) {
+    return AECM_BAD_PARAMETER_ERROR;
+  }
+  aecm->aecmCore->cngMode = config.cngMode;
+
+  if (config.echoMode < 0 || config.echoMode > 4) {
+    return AECM_BAD_PARAMETER_ERROR;
+  }
+  aecm->echoMode = config.echoMode;
+
+  if (aecm->echoMode == 0) {
+    aecm->aecmCore->supGain = SUPGAIN_DEFAULT >> 3;
+    aecm->aecmCore->supGainOld = SUPGAIN_DEFAULT >> 3;
+    aecm->aecmCore->supGainErrParamA = SUPGAIN_ERROR_PARAM_A >> 3;
+    aecm->aecmCore->supGainErrParamD = SUPGAIN_ERROR_PARAM_D >> 3;
+    aecm->aecmCore->supGainErrParamDiffAB =
+        (SUPGAIN_ERROR_PARAM_A >> 3) - (SUPGAIN_ERROR_PARAM_B >> 3);
+    aecm->aecmCore->supGainErrParamDiffBD =
+        (SUPGAIN_ERROR_PARAM_B >> 3) - (SUPGAIN_ERROR_PARAM_D >> 3);
+  } else if (aecm->echoMode == 1) {
+    aecm->aecmCore->supGain = SUPGAIN_DEFAULT >> 2;
+    aecm->aecmCore->supGainOld = SUPGAIN_DEFAULT >> 2;
+    aecm->aecmCore->supGainErrParamA = SUPGAIN_ERROR_PARAM_A >> 2;
+    aecm->aecmCore->supGainErrParamD = SUPGAIN_ERROR_PARAM_D >> 2;
+    aecm->aecmCore->supGainErrParamDiffAB =
+        (SUPGAIN_ERROR_PARAM_A >> 2) - (SUPGAIN_ERROR_PARAM_B >> 2);
+    aecm->aecmCore->supGainErrParamDiffBD =
+        (SUPGAIN_ERROR_PARAM_B >> 2) - (SUPGAIN_ERROR_PARAM_D >> 2);
+  } else if (aecm->echoMode == 2) {
+    aecm->aecmCore->supGain = SUPGAIN_DEFAULT >> 1;
+    aecm->aecmCore->supGainOld = SUPGAIN_DEFAULT >> 1;
+    aecm->aecmCore->supGainErrParamA = SUPGAIN_ERROR_PARAM_A >> 1;
+    aecm->aecmCore->supGainErrParamD = SUPGAIN_ERROR_PARAM_D >> 1;
+    aecm->aecmCore->supGainErrParamDiffAB =
+        (SUPGAIN_ERROR_PARAM_A >> 1) - (SUPGAIN_ERROR_PARAM_B >> 1);
+    aecm->aecmCore->supGainErrParamDiffBD =
+        (SUPGAIN_ERROR_PARAM_B >> 1) - (SUPGAIN_ERROR_PARAM_D >> 1);
+  } else if (aecm->echoMode == 3) {
+    aecm->aecmCore->supGain = SUPGAIN_DEFAULT;
+    aecm->aecmCore->supGainOld = SUPGAIN_DEFAULT;
+    aecm->aecmCore->supGainErrParamA = SUPGAIN_ERROR_PARAM_A;
+    aecm->aecmCore->supGainErrParamD = SUPGAIN_ERROR_PARAM_D;
+    aecm->aecmCore->supGainErrParamDiffAB =
+        SUPGAIN_ERROR_PARAM_A - SUPGAIN_ERROR_PARAM_B;
+    aecm->aecmCore->supGainErrParamDiffBD =
+        SUPGAIN_ERROR_PARAM_B - SUPGAIN_ERROR_PARAM_D;
+  } else if (aecm->echoMode == 4) {
+    aecm->aecmCore->supGain = SUPGAIN_DEFAULT << 1;
+    aecm->aecmCore->supGainOld = SUPGAIN_DEFAULT << 1;
+    aecm->aecmCore->supGainErrParamA = SUPGAIN_ERROR_PARAM_A << 1;
+    aecm->aecmCore->supGainErrParamD = SUPGAIN_ERROR_PARAM_D << 1;
+    aecm->aecmCore->supGainErrParamDiffAB =
+        (SUPGAIN_ERROR_PARAM_A << 1) - (SUPGAIN_ERROR_PARAM_B << 1);
+    aecm->aecmCore->supGainErrParamDiffBD =
+        (SUPGAIN_ERROR_PARAM_B << 1) - (SUPGAIN_ERROR_PARAM_D << 1);
+  }
+
+  return 0;
+}
+
+int32_t WebRtcAecm_InitEchoPath(void* aecmInst,
+                                const void* echo_path,
+                                size_t size_bytes) {
+  AecMobile* aecm = static_cast<AecMobile*>(aecmInst);
+  const int16_t* echo_path_ptr = static_cast<const int16_t*>(echo_path);
+
+  if (aecmInst == NULL) {
+    return -1;
+  }
+  if (echo_path == NULL) {
+    return AECM_NULL_POINTER_ERROR;
+  }
+  if (size_bytes != WebRtcAecm_echo_path_size_bytes()) {
+    // Input channel size does not match the size of AECM
+    return AECM_BAD_PARAMETER_ERROR;
+  }
+  if (aecm->initFlag != kInitCheck) {
+    return AECM_UNINITIALIZED_ERROR;
+  }
+
+  WebRtcAecm_InitEchoPathCore(aecm->aecmCore, echo_path_ptr);
+
+  return 0;
+}
+
+int32_t WebRtcAecm_GetEchoPath(void* aecmInst,
+                               void* echo_path,
+                               size_t size_bytes) {
+  AecMobile* aecm = static_cast<AecMobile*>(aecmInst);
+  int16_t* echo_path_ptr = static_cast<int16_t*>(echo_path);
+
+  if (aecmInst == NULL) {
+    return -1;
+  }
+  if (echo_path == NULL) {
+    return AECM_NULL_POINTER_ERROR;
+  }
+  if (size_bytes != WebRtcAecm_echo_path_size_bytes()) {
+    // Input channel size does not match the size of AECM
+    return AECM_BAD_PARAMETER_ERROR;
+  }
+  if (aecm->initFlag != kInitCheck) {
+    return AECM_UNINITIALIZED_ERROR;
+  }
+
+  memcpy(echo_path_ptr, aecm->aecmCore->channelStored, size_bytes);
+  return 0;
+}
+
+size_t WebRtcAecm_echo_path_size_bytes() {
+  return (PART_LEN1 * sizeof(int16_t));
+}
+
+static int WebRtcAecm_EstBufDelay(AecMobile* aecm, short msInSndCardBuf) {
+  short delayNew, nSampSndCard;
+  short nSampFar = (short)WebRtc_available_read(aecm->farendBuf);
+  short diff;
+
+  nSampSndCard = msInSndCardBuf * kSampMsNb * aecm->aecmCore->mult;
+
+  delayNew = nSampSndCard - nSampFar;
+
+  if (delayNew < FRAME_LEN) {
+    WebRtc_MoveReadPtr(aecm->farendBuf, FRAME_LEN);
+    delayNew += FRAME_LEN;
+  }
+
+  aecm->filtDelay =
+      WEBRTC_SPL_MAX(0, (8 * aecm->filtDelay + 2 * delayNew) / 10);
+
+  diff = aecm->filtDelay - aecm->knownDelay;
+  if (diff > 224) {
+    if (aecm->lastDelayDiff < 96) {
+      aecm->timeForDelayChange = 0;
+    } else {
+      aecm->timeForDelayChange++;
+    }
+  } else if (diff < 96 && aecm->knownDelay > 0) {
+    if (aecm->lastDelayDiff > 224) {
+      aecm->timeForDelayChange = 0;
+    } else {
+      aecm->timeForDelayChange++;
+    }
+  } else {
+    aecm->timeForDelayChange = 0;
+  }
+  aecm->lastDelayDiff = diff;
+
+  if (aecm->timeForDelayChange > 25) {
+    aecm->knownDelay = WEBRTC_SPL_MAX((int)aecm->filtDelay - 160, 0);
+  }
+  return 0;
+}
+
+static int WebRtcAecm_DelayComp(AecMobile* aecm) {
+  int nSampFar = (int)WebRtc_available_read(aecm->farendBuf);
+  int nSampSndCard, delayNew, nSampAdd;
+  const int maxStuffSamp = 10 * FRAME_LEN;
+
+  nSampSndCard = aecm->msInSndCardBuf * kSampMsNb * aecm->aecmCore->mult;
+  delayNew = nSampSndCard - nSampFar;
+
+  if (delayNew > FAR_BUF_LEN - FRAME_LEN * aecm->aecmCore->mult) {
+    // The difference of the buffer sizes is larger than the maximum
+    // allowed known delay. Compensate by stuffing the buffer.
+    nSampAdd =
+        (int)(WEBRTC_SPL_MAX(((nSampSndCard >> 1) - nSampFar), FRAME_LEN));
+    nSampAdd = WEBRTC_SPL_MIN(nSampAdd, maxStuffSamp);
+
+    WebRtc_MoveReadPtr(aecm->farendBuf, -nSampAdd);
+    aecm->delayChange = 1;  // the delay needs to be updated
+  }
+
+  return 0;
+}
+
+}  // namespace webrtc

VocieProcess/modules/audio_processing/aecm/echo_control_mobile.h

@@ -0,0 +1,209 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef MODULES_AUDIO_PROCESSING_AECM_ECHO_CONTROL_MOBILE_H_
+#define MODULES_AUDIO_PROCESSING_AECM_ECHO_CONTROL_MOBILE_H_
+
+#include <stddef.h>
+#include <stdint.h>
+
+namespace webrtc {
+
+enum { AecmFalse = 0, AecmTrue };
+
+// Errors
+#define AECM_UNSPECIFIED_ERROR 12000
+#define AECM_UNSUPPORTED_FUNCTION_ERROR 12001
+#define AECM_UNINITIALIZED_ERROR 12002
+#define AECM_NULL_POINTER_ERROR 12003
+#define AECM_BAD_PARAMETER_ERROR 12004
+
+// Warnings
+#define AECM_BAD_PARAMETER_WARNING 12100
+
+typedef struct {
+  int16_t cngMode;   // AECM_FALSE, AECM_TRUE (default)
+  int16_t echoMode;  // 0, 1, 2, 3 (default), 4
+} AecmConfig;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * Allocates the memory needed by the AECM. The memory needs to be
+ * initialized separately using the WebRtcAecm_Init() function.
+ * Returns a pointer to the instance and a nullptr at failure.
+ */
+void* WebRtcAecm_Create();
+
+/*
+ * This function releases the memory allocated by WebRtcAecm_Create()
+ *
+ * Inputs                       Description
+ * -------------------------------------------------------------------
+ * void*    aecmInst            Pointer to the AECM instance
+ */
+void WebRtcAecm_Free(void* aecmInst);
+
+/*
+ * Initializes an AECM instance.
+ *
+ * Inputs                       Description
+ * -------------------------------------------------------------------
+ * void*          aecmInst      Pointer to the AECM instance
+ * int32_t        sampFreq      Sampling frequency of data
+ *
+ * Outputs                      Description
+ * -------------------------------------------------------------------
+ * int32_t        return        0: OK
+ *                              1200-12004,12100: error/warning
+ */
+int32_t WebRtcAecm_Init(void* aecmInst, int32_t sampFreq);
+
+/*
+ * Inserts an 80 or 160 sample block of data into the farend buffer.
+ *
+ * Inputs                       Description
+ * -------------------------------------------------------------------
+ * void*          aecmInst      Pointer to the AECM instance
+ * int16_t*       farend        In buffer containing one frame of
+ *                              farend signal
+ * int16_t        nrOfSamples   Number of samples in farend buffer
+ *
+ * Outputs                      Description
+ * -------------------------------------------------------------------
+ * int32_t        return        0: OK
+ *                              1200-12004,12100: error/warning
+ */
+int32_t WebRtcAecm_BufferFarend(void* aecmInst,
+                                const int16_t* farend,
+                                size_t nrOfSamples);
+
+/*
+ * Reports any errors that would arise when buffering a farend buffer.
+ *
+ * Inputs                       Description
+ * -------------------------------------------------------------------
+ * void*          aecmInst      Pointer to the AECM instance
+ * int16_t*       farend        In buffer containing one frame of
+ *                              farend signal
+ * int16_t        nrOfSamples   Number of samples in farend buffer
+ *
+ * Outputs                      Description
+ * -------------------------------------------------------------------
+ * int32_t        return        0: OK
+ *                              1200-12004,12100: error/warning
+ */
+int32_t WebRtcAecm_GetBufferFarendError(void* aecmInst,
+                                        const int16_t* farend,
+                                        size_t nrOfSamples);
+
+/*
+ * Runs the AECM on an 80 or 160 sample blocks of data.
+ *
+ * Inputs                        Description
+ * -------------------------------------------------------------------
+ * void*          aecmInst       Pointer to the AECM instance
+ * int16_t*       nearendNoisy   In buffer containing one frame of
+ *                               reference nearend+echo signal. If
+ *                               noise reduction is active, provide
+ *                               the noisy signal here.
+ * int16_t*       nearendClean   In buffer containing one frame of
+ *                               nearend+echo signal. If noise
+ *                               reduction is active, provide the
+ *                               clean signal here. Otherwise pass a
+ *                               NULL pointer.
+ * int16_t        nrOfSamples    Number of samples in nearend buffer
+ * int16_t        msInSndCardBuf Delay estimate for sound card and
+ *                               system buffers
+ *
+ * Outputs                       Description
+ * -------------------------------------------------------------------
+ * int16_t*       out            Out buffer, one frame of processed nearend
+ * int32_t        return         0: OK
+ *                               1200-12004,12100: error/warning
+ */
+int32_t WebRtcAecm_Process(void* aecmInst,
+                           const int16_t* nearendNoisy,
+                           const int16_t* nearendClean,
+                           int16_t* out,
+                           size_t nrOfSamples,
+                           int16_t msInSndCardBuf);
+
+/*
+ * This function enables the user to set certain parameters on-the-fly
+ *
+ * Inputs                       Description
+ * -------------------------------------------------------------------
+ * void*          aecmInst      Pointer to the AECM instance
+ * AecmConfig     config        Config instance that contains all
+ *                              properties to be set
+ *
+ * Outputs                      Description
+ * -------------------------------------------------------------------
+ * int32_t        return        0: OK
+ *                              1200-12004,12100: error/warning
+ */
+int32_t WebRtcAecm_set_config(void* aecmInst, AecmConfig config);
+
+/*
+ * This function enables the user to set the echo path on-the-fly.
+ *
+ * Inputs                       Description
+ * -------------------------------------------------------------------
+ * void*        aecmInst        Pointer to the AECM instance
+ * void*        echo_path       Pointer to the echo path to be set
+ * size_t       size_bytes      Size in bytes of the echo path
+ *
+ * Outputs                      Description
+ * -------------------------------------------------------------------
+ * int32_t      return          0: OK
+ *                              1200-12004,12100: error/warning
+ */
+int32_t WebRtcAecm_InitEchoPath(void* aecmInst,
+                                const void* echo_path,
+                                size_t size_bytes);
+
+/*
+ * This function enables the user to get the currently used echo path
+ * on-the-fly
+ *
+ * Inputs                       Description
+ * -------------------------------------------------------------------
+ * void*        aecmInst        Pointer to the AECM instance
+ * void*        echo_path       Pointer to echo path
+ * size_t       size_bytes      Size in bytes of the echo path
+ *
+ * Outputs                      Description
+ * -------------------------------------------------------------------
+ * int32_t      return          0: OK
+ *                              1200-12004,12100: error/warning
+ */
+int32_t WebRtcAecm_GetEchoPath(void* aecmInst,
+                               void* echo_path,
+                               size_t size_bytes);
+
+/*
+ * This function enables the user to get the echo path size in bytes
+ *
+ * Outputs                      Description
+ * -------------------------------------------------------------------
+ * size_t       return          Size in bytes
+ */
+size_t WebRtcAecm_echo_path_size_bytes();
+
+#ifdef __cplusplus
+}
+#endif
+
+}  // namespace webrtc
+
+#endif  // MODULES_AUDIO_PROCESSING_AECM_ECHO_CONTROL_MOBILE_H_

VocieProcess/modules/audio_processing/utility/delay_estimator.cc

@@ -0,0 +1,708 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "modules/audio_processing/utility/delay_estimator.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+#include <algorithm>
+
+#include "rtc_base/checks.h"
+
+namespace webrtc {
+
+namespace {
+
+// Number of right shifts for scaling is linearly depending on number of bits in
+// the far-end binary spectrum.
+static const int kShiftsAtZero = 13;  // Right shifts at zero binary spectrum.
+static const int kShiftsLinearSlope = 3;
+
+static const int32_t kProbabilityOffset = 1024;      // 2 in Q9.
+static const int32_t kProbabilityLowerLimit = 8704;  // 17 in Q9.
+static const int32_t kProbabilityMinSpread = 2816;   // 5.5 in Q9.
+
+// Robust validation settings
+static const float kHistogramMax = 3000.f;
+static const float kLastHistogramMax = 250.f;
+static const float kMinHistogramThreshold = 1.5f;
+static const int kMinRequiredHits = 10;
+static const int kMaxHitsWhenPossiblyNonCausal = 10;
+static const int kMaxHitsWhenPossiblyCausal = 1000;
+static const float kQ14Scaling = 1.f / (1 << 14);  // Scaling by 2^14 to get Q0.
+static const float kFractionSlope = 0.05f;
+static const float kMinFractionWhenPossiblyCausal = 0.5f;
+static const float kMinFractionWhenPossiblyNonCausal = 0.25f;
+
+}  // namespace
+
+// Counts and returns number of bits of a 32-bit word.
+static int BitCount(uint32_t u32) {
+  uint32_t tmp =
+      u32 - ((u32 >> 1) & 033333333333) - ((u32 >> 2) & 011111111111);
+  tmp = ((tmp + (tmp >> 3)) & 030707070707);
+  tmp = (tmp + (tmp >> 6));
+  tmp = (tmp + (tmp >> 12) + (tmp >> 24)) & 077;
+
+  return ((int)tmp);
+}
+
+// Compares the `binary_vector` with all rows of the `binary_matrix` and counts
+// per row the number of times they have the same value.
+//
+// Inputs:
+//      - binary_vector     : binary "vector" stored in a long
+//      - binary_matrix     : binary "matrix" stored as a vector of long
+//      - matrix_size       : size of binary "matrix"
+//
+// Output:
+//      - bit_counts        : "Vector" stored as a long, containing for each
+//                            row the number of times the matrix row and the
+//                            input vector have the same value
+//
+static void BitCountComparison(uint32_t binary_vector,
+                               const uint32_t* binary_matrix,
+                               int matrix_size,
+                               int32_t* bit_counts) {
+  int n = 0;
+
+  // Compare `binary_vector` with all rows of the `binary_matrix`
+  for (; n < matrix_size; n++) {
+    bit_counts[n] = (int32_t)BitCount(binary_vector ^ binary_matrix[n]);
+  }
+}
+
+// Collects necessary statistics for the HistogramBasedValidation().  This
+// function has to be called prior to calling HistogramBasedValidation().  The
+// statistics updated and used by the HistogramBasedValidation() are:
+//  1. the number of `candidate_hits`, which states for how long we have had the
+//     same `candidate_delay`
+//  2. the `histogram` of candidate delays over time.  This histogram is
+//     weighted with respect to a reliability measure and time-varying to cope
+//     with possible delay shifts.
+// For further description see commented code.
+//
+// Inputs:
+//  - candidate_delay   : The delay to validate.
+//  - valley_depth_q14  : The cost function has a valley/minimum at the
+//                        `candidate_delay` location.  `valley_depth_q14` is the
+//                        cost function difference between the minimum and
+//                        maximum locations.  The value is in the Q14 domain.
+//  - valley_level_q14  : Is the cost function value at the minimum, in Q14.
+static void UpdateRobustValidationStatistics(BinaryDelayEstimator* self,
+                                             int candidate_delay,
+                                             int32_t valley_depth_q14,
+                                             int32_t valley_level_q14) {
+  const float valley_depth = valley_depth_q14 * kQ14Scaling;
+  float decrease_in_last_set = valley_depth;
+  const int max_hits_for_slow_change = (candidate_delay < self->last_delay)
+                                           ? kMaxHitsWhenPossiblyNonCausal
+                                           : kMaxHitsWhenPossiblyCausal;
+  int i = 0;
+
+  RTC_DCHECK_EQ(self->history_size, self->farend->history_size);
+  // Reset `candidate_hits` if we have a new candidate.
+  if (candidate_delay != self->last_candidate_delay) {
+    self->candidate_hits = 0;
+    self->last_candidate_delay = candidate_delay;
+  }
+  self->candidate_hits++;
+
+  // The `histogram` is updated differently across the bins.
+  // 1. The `candidate_delay` histogram bin is increased with the
+  //    `valley_depth`, which is a simple measure of how reliable the
+  //    `candidate_delay` is.  The histogram is not increased above
+  //    `kHistogramMax`.
+  self->histogram[candidate_delay] += valley_depth;
+  if (self->histogram[candidate_delay] > kHistogramMax) {
+    self->histogram[candidate_delay] = kHistogramMax;
+  }
+  // 2. The histogram bins in the neighborhood of `candidate_delay` are
+  //    unaffected.  The neighborhood is defined as x + {-2, -1, 0, 1}.
+  // 3. The histogram bins in the neighborhood of `last_delay` are decreased
+  //    with `decrease_in_last_set`.  This value equals the difference between
+  //    the cost function values at the locations `candidate_delay` and
+  //    `last_delay` until we reach `max_hits_for_slow_change` consecutive hits
+  //    at the `candidate_delay`.  If we exceed this amount of hits the
+  //    `candidate_delay` is a "potential" candidate and we start decreasing
+  //    these histogram bins more rapidly with `valley_depth`.
+  if (self->candidate_hits < max_hits_for_slow_change) {
+    decrease_in_last_set =
+        (self->mean_bit_counts[self->compare_delay] - valley_level_q14) *
+        kQ14Scaling;
+  }
+  // 4. All other bins are decreased with `valley_depth`.
+  // TODO(bjornv): Investigate how to make this loop more efficient.  Split up
+  // the loop?  Remove parts that doesn't add too much.
+  for (i = 0; i < self->history_size; ++i) {
+    int is_in_last_set = (i >= self->last_delay - 2) &&
+                         (i <= self->last_delay + 1) && (i != candidate_delay);
+    int is_in_candidate_set =
+        (i >= candidate_delay - 2) && (i <= candidate_delay + 1);
+    self->histogram[i] -=
+        decrease_in_last_set * is_in_last_set +
+        valley_depth * (!is_in_last_set && !is_in_candidate_set);
+    // 5. No histogram bin can go below 0.
+    if (self->histogram[i] < 0) {
+      self->histogram[i] = 0;
+    }
+  }
+}
+
+// Validates the `candidate_delay`, estimated in WebRtc_ProcessBinarySpectrum(),
+// based on a mix of counting concurring hits with a modified histogram
+// of recent delay estimates.  In brief a candidate is valid (returns 1) if it
+// is the most likely according to the histogram.  There are a couple of
+// exceptions that are worth mentioning:
+//  1. If the `candidate_delay` < `last_delay` it can be that we are in a
+//     non-causal state, breaking a possible echo control algorithm.  Hence, we
+//     open up for a quicker change by allowing the change even if the
+//     `candidate_delay` is not the most likely one according to the histogram.
+//  2. There's a minimum number of hits (kMinRequiredHits) and the histogram
+//     value has to reached a minimum (kMinHistogramThreshold) to be valid.
+//  3. The action is also depending on the filter length used for echo control.
+//     If the delay difference is larger than what the filter can capture, we
+//     also move quicker towards a change.
+// For further description see commented code.
+//
+// Input:
+//  - candidate_delay     : The delay to validate.
+//
+// Return value:
+//  - is_histogram_valid  : 1 - The `candidate_delay` is valid.
+//                          0 - Otherwise.
+static int HistogramBasedValidation(const BinaryDelayEstimator* self,
+                                    int candidate_delay) {
+  float fraction = 1.f;
+  float histogram_threshold = self->histogram[self->compare_delay];
+  const int delay_difference = candidate_delay - self->last_delay;
+  int is_histogram_valid = 0;
+
+  // The histogram based validation of `candidate_delay` is done by comparing
+  // the `histogram` at bin `candidate_delay` with a `histogram_threshold`.
+  // This `histogram_threshold` equals a `fraction` of the `histogram` at bin
+  // `last_delay`.  The `fraction` is a piecewise linear function of the
+  // `delay_difference` between the `candidate_delay` and the `last_delay`
+  // allowing for a quicker move if
+  //  i) a potential echo control filter can not handle these large differences.
+  // ii) keeping `last_delay` instead of updating to `candidate_delay` could
+  //     force an echo control into a non-causal state.
+  // We further require the histogram to have reached a minimum value of
+  // `kMinHistogramThreshold`.  In addition, we also require the number of
+  // `candidate_hits` to be more than `kMinRequiredHits` to remove spurious
+  // values.
+
+  // Calculate a comparison histogram value (`histogram_threshold`) that is
+  // depending on the distance between the `candidate_delay` and `last_delay`.
+  // TODO(bjornv): How much can we gain by turning the fraction calculation
+  // into tables?
+  if (delay_difference > self->allowed_offset) {
+    fraction = 1.f - kFractionSlope * (delay_difference - self->allowed_offset);
+    fraction = (fraction > kMinFractionWhenPossiblyCausal
+                    ? fraction
+                    : kMinFractionWhenPossiblyCausal);
+  } else if (delay_difference < 0) {
+    fraction =
+        kMinFractionWhenPossiblyNonCausal - kFractionSlope * delay_difference;
+    fraction = (fraction > 1.f ? 1.f : fraction);
+  }
+  histogram_threshold *= fraction;
+  histogram_threshold =
+      (histogram_threshold > kMinHistogramThreshold ? histogram_threshold
+                                                    : kMinHistogramThreshold);
+
+  is_histogram_valid =
+      (self->histogram[candidate_delay] >= histogram_threshold) &&
+      (self->candidate_hits > kMinRequiredHits);
+
+  return is_histogram_valid;
+}
+
+// Performs a robust validation of the `candidate_delay` estimated in
+// WebRtc_ProcessBinarySpectrum().  The algorithm takes the
+// `is_instantaneous_valid` and the `is_histogram_valid` and combines them
+// into a robust validation.  The HistogramBasedValidation() has to be called
+// prior to this call.
+// For further description on how the combination is done, see commented code.
+//
+// Inputs:
+//  - candidate_delay         : The delay to validate.
+//  - is_instantaneous_valid  : The instantaneous validation performed in
+//                              WebRtc_ProcessBinarySpectrum().
+//  - is_histogram_valid      : The histogram based validation.
+//
+// Return value:
+//  - is_robust               : 1 - The candidate_delay is valid according to a
+//                                  combination of the two inputs.
+//                            : 0 - Otherwise.
+static int RobustValidation(const BinaryDelayEstimator* self,
+                            int candidate_delay,
+                            int is_instantaneous_valid,
+                            int is_histogram_valid) {
+  int is_robust = 0;
+
+  // The final robust validation is based on the two algorithms; 1) the
+  // `is_instantaneous_valid` and 2) the histogram based with result stored in
+  // `is_histogram_valid`.
+  //   i) Before we actually have a valid estimate (`last_delay` == -2), we say
+  //      a candidate is valid if either algorithm states so
+  //      (`is_instantaneous_valid` OR `is_histogram_valid`).
+  is_robust =
+      (self->last_delay < 0) && (is_instantaneous_valid || is_histogram_valid);
+  //  ii) Otherwise, we need both algorithms to be certain
+  //      (`is_instantaneous_valid` AND `is_histogram_valid`)
+  is_robust |= is_instantaneous_valid && is_histogram_valid;
+  // iii) With one exception, i.e., the histogram based algorithm can overrule
+  //      the instantaneous one if `is_histogram_valid` = 1 and the histogram
+  //      is significantly strong.
+  is_robust |= is_histogram_valid &&
+               (self->histogram[candidate_delay] > self->last_delay_histogram);
+
+  return is_robust;
+}
+
+void WebRtc_FreeBinaryDelayEstimatorFarend(BinaryDelayEstimatorFarend* self) {
+  if (self == NULL) {
+    return;
+  }
+
+  free(self->binary_far_history);
+  self->binary_far_history = NULL;
+
+  free(self->far_bit_counts);
+  self->far_bit_counts = NULL;
+
+  free(self);
+}
+
+BinaryDelayEstimatorFarend* WebRtc_CreateBinaryDelayEstimatorFarend(
+    int history_size) {
+  BinaryDelayEstimatorFarend* self = NULL;
+
+  if (history_size > 1) {
+    // Sanity conditions fulfilled.
+    self = static_cast<BinaryDelayEstimatorFarend*>(
+        malloc(sizeof(BinaryDelayEstimatorFarend)));
+  }
+  if (self == NULL) {
+    return NULL;
+  }
+
+  self->history_size = 0;
+  self->binary_far_history = NULL;
+  self->far_bit_counts = NULL;
+  if (WebRtc_AllocateFarendBufferMemory(self, history_size) == 0) {
+    WebRtc_FreeBinaryDelayEstimatorFarend(self);
+    self = NULL;
+  }
+  return self;
+}
+
+int WebRtc_AllocateFarendBufferMemory(BinaryDelayEstimatorFarend* self,
+                                      int history_size) {
+  RTC_DCHECK(self);
+  // (Re-)Allocate memory for history buffers.
+  self->binary_far_history = static_cast<uint32_t*>(
+      realloc(self->binary_far_history,
+              history_size * sizeof(*self->binary_far_history)));
+  self->far_bit_counts = static_cast<int*>(realloc(
+      self->far_bit_counts, history_size * sizeof(*self->far_bit_counts)));
+  if ((self->binary_far_history == NULL) || (self->far_bit_counts == NULL)) {
+    history_size = 0;
+  }
+  // Fill with zeros if we have expanded the buffers.
+  if (history_size > self->history_size) {
+    int size_diff = history_size - self->history_size;
+    memset(&self->binary_far_history[self->history_size], 0,
+           sizeof(*self->binary_far_history) * size_diff);
+    memset(&self->far_bit_counts[self->history_size], 0,
+           sizeof(*self->far_bit_counts) * size_diff);
+  }
+  self->history_size = history_size;
+
+  return self->history_size;
+}
+
+void WebRtc_InitBinaryDelayEstimatorFarend(BinaryDelayEstimatorFarend* self) {
+  RTC_DCHECK(self);
+  memset(self->binary_far_history, 0, sizeof(uint32_t) * self->history_size);
+  memset(self->far_bit_counts, 0, sizeof(int) * self->history_size);
+}
+
+void WebRtc_SoftResetBinaryDelayEstimatorFarend(
+    BinaryDelayEstimatorFarend* self,
+    int delay_shift) {
+  int abs_shift = abs(delay_shift);
+  int shift_size = 0;
+  int dest_index = 0;
+  int src_index = 0;
+  int padding_index = 0;
+
+  RTC_DCHECK(self);
+  shift_size = self->history_size - abs_shift;
+  RTC_DCHECK_GT(shift_size, 0);
+  if (delay_shift == 0) {
+    return;
+  } else if (delay_shift > 0) {
+    dest_index = abs_shift;
+  } else if (delay_shift < 0) {
+    src_index = abs_shift;
+    padding_index = shift_size;
+  }
+
+  // Shift and zero pad buffers.
+  memmove(&self->binary_far_history[dest_index],
+          &self->binary_far_history[src_index],
+          sizeof(*self->binary_far_history) * shift_size);
+  memset(&self->binary_far_history[padding_index], 0,
+         sizeof(*self->binary_far_history) * abs_shift);
+  memmove(&self->far_bit_counts[dest_index], &self->far_bit_counts[src_index],
+          sizeof(*self->far_bit_counts) * shift_size);
+  memset(&self->far_bit_counts[padding_index], 0,
+         sizeof(*self->far_bit_counts) * abs_shift);
+}
+
+void WebRtc_AddBinaryFarSpectrum(BinaryDelayEstimatorFarend* handle,
+                                 uint32_t binary_far_spectrum) {
+  RTC_DCHECK(handle);
+  // Shift binary spectrum history and insert current `binary_far_spectrum`.
+  memmove(&(handle->binary_far_history[1]), &(handle->binary_far_history[0]),
+          (handle->history_size - 1) * sizeof(uint32_t));
+  handle->binary_far_history[0] = binary_far_spectrum;
+
+  // Shift history of far-end binary spectrum bit counts and insert bit count
+  // of current `binary_far_spectrum`.
+  memmove(&(handle->far_bit_counts[1]), &(handle->far_bit_counts[0]),
+          (handle->history_size - 1) * sizeof(int));
+  handle->far_bit_counts[0] = BitCount(binary_far_spectrum);
+}
+
+void WebRtc_FreeBinaryDelayEstimator(BinaryDelayEstimator* self) {
+  if (self == NULL) {
+    return;
+  }
+
+  free(self->mean_bit_counts);
+  self->mean_bit_counts = NULL;
+
+  free(self->bit_counts);
+  self->bit_counts = NULL;
+
+  free(self->binary_near_history);
+  self->binary_near_history = NULL;
+
+  free(self->histogram);
+  self->histogram = NULL;
+
+  // BinaryDelayEstimator does not have ownership of `farend`, hence we do not
+  // free the memory here. That should be handled separately by the user.
+  self->farend = NULL;
+
+  free(self);
+}
+
+BinaryDelayEstimator* WebRtc_CreateBinaryDelayEstimator(
+    BinaryDelayEstimatorFarend* farend,
+    int max_lookahead) {
+  BinaryDelayEstimator* self = NULL;
+
+  if ((farend != NULL) && (max_lookahead >= 0)) {
+    // Sanity conditions fulfilled.
+    self = static_cast<BinaryDelayEstimator*>(
+        malloc(sizeof(BinaryDelayEstimator)));
+  }
+  if (self == NULL) {
+    return NULL;
+  }
+
+  self->farend = farend;
+  self->near_history_size = max_lookahead + 1;
+  self->history_size = 0;
+  self->robust_validation_enabled = 0;  // Disabled by default.
+  self->allowed_offset = 0;
+
+  self->lookahead = max_lookahead;
+
+  // Allocate memory for spectrum and history buffers.
+  self->mean_bit_counts = NULL;
+  self->bit_counts = NULL;
+  self->histogram = NULL;
+  self->binary_near_history = static_cast<uint32_t*>(
+      malloc((max_lookahead + 1) * sizeof(*self->binary_near_history)));
+  if (self->binary_near_history == NULL ||
+      WebRtc_AllocateHistoryBufferMemory(self, farend->history_size) == 0) {
+    WebRtc_FreeBinaryDelayEstimator(self);
+    self = NULL;
+  }
+
+  return self;
+}
+
+int WebRtc_AllocateHistoryBufferMemory(BinaryDelayEstimator* self,
+                                       int history_size) {
+  BinaryDelayEstimatorFarend* far = self->farend;
+  // (Re-)Allocate memory for spectrum and history buffers.
+  if (history_size != far->history_size) {
+    // Only update far-end buffers if we need.
+    history_size = WebRtc_AllocateFarendBufferMemory(far, history_size);
+  }
+  // The extra array element in `mean_bit_counts` and `histogram` is a dummy
+  // element only used while `last_delay` == -2, i.e., before we have a valid
+  // estimate.
+  self->mean_bit_counts = static_cast<int32_t*>(
+      realloc(self->mean_bit_counts,
+              (history_size + 1) * sizeof(*self->mean_bit_counts)));
+  self->bit_counts = static_cast<int32_t*>(
+      realloc(self->bit_counts, history_size * sizeof(*self->bit_counts)));
+  self->histogram = static_cast<float*>(
+      realloc(self->histogram, (history_size + 1) * sizeof(*self->histogram)));
+
+  if ((self->mean_bit_counts == NULL) || (self->bit_counts == NULL) ||
+      (self->histogram == NULL)) {
+    history_size = 0;
+  }
+  // Fill with zeros if we have expanded the buffers.
+  if (history_size > self->history_size) {
+    int size_diff = history_size - self->history_size;
+    memset(&self->mean_bit_counts[self->history_size], 0,
+           sizeof(*self->mean_bit_counts) * size_diff);
+    memset(&self->bit_counts[self->history_size], 0,
+           sizeof(*self->bit_counts) * size_diff);
+    memset(&self->histogram[self->history_size], 0,
+           sizeof(*self->histogram) * size_diff);
+  }
+  self->history_size = history_size;
+
+  return self->history_size;
+}
+
+void WebRtc_InitBinaryDelayEstimator(BinaryDelayEstimator* self) {
+  int i = 0;
+  RTC_DCHECK(self);
+
+  memset(self->bit_counts, 0, sizeof(int32_t) * self->history_size);
+  memset(self->binary_near_history, 0,
+         sizeof(uint32_t) * self->near_history_size);
+  for (i = 0; i <= self->history_size; ++i) {
+    self->mean_bit_counts[i] = (20 << 9);  // 20 in Q9.
+    self->histogram[i] = 0.f;
+  }
+  self->minimum_probability = kMaxBitCountsQ9;          // 32 in Q9.
+  self->last_delay_probability = (int)kMaxBitCountsQ9;  // 32 in Q9.
+
+  // Default return value if we're unable to estimate. -1 is used for errors.
+  self->last_delay = -2;
+
+  self->last_candidate_delay = -2;
+  self->compare_delay = self->history_size;
+  self->candidate_hits = 0;
+  self->last_delay_histogram = 0.f;
+}
+
+int WebRtc_SoftResetBinaryDelayEstimator(BinaryDelayEstimator* self,
+                                         int delay_shift) {
+  int lookahead = 0;
+  RTC_DCHECK(self);
+  lookahead = self->lookahead;
+  self->lookahead -= delay_shift;
+  if (self->lookahead < 0) {
+    self->lookahead = 0;
+  }
+  if (self->lookahead > self->near_history_size - 1) {
+    self->lookahead = self->near_history_size - 1;
+  }
+  return lookahead - self->lookahead;
+}
+
+int WebRtc_ProcessBinarySpectrum(BinaryDelayEstimator* self,
+                                 uint32_t binary_near_spectrum) {
+  int i = 0;
+  int candidate_delay = -1;
+  int valid_candidate = 0;
+
+  int32_t value_best_candidate = kMaxBitCountsQ9;
+  int32_t value_worst_candidate = 0;
+  int32_t valley_depth = 0;
+
+  RTC_DCHECK(self);
+  if (self->farend->history_size != self->history_size) {
+    // Non matching history sizes.
+    return -1;
+  }
+  if (self->near_history_size > 1) {
+    // If we apply lookahead, shift near-end binary spectrum history. Insert
+    // current `binary_near_spectrum` and pull out the delayed one.
+    memmove(&(self->binary_near_history[1]), &(self->binary_near_history[0]),
+            (self->near_history_size - 1) * sizeof(uint32_t));
+    self->binary_near_history[0] = binary_near_spectrum;
+    binary_near_spectrum = self->binary_near_history[self->lookahead];
+  }
+
+  // Compare with delayed spectra and store the `bit_counts` for each delay.
+  BitCountComparison(binary_near_spectrum, self->farend->binary_far_history,
+                     self->history_size, self->bit_counts);
+
+  // Update `mean_bit_counts`, which is the smoothed version of `bit_counts`.
+  for (i = 0; i < self->history_size; i++) {
+    // `bit_counts` is constrained to [0, 32], meaning we can smooth with a
+    // factor up to 2^26. We use Q9.
+    int32_t bit_count = (self->bit_counts[i] << 9);  // Q9.
+
+    // Update `mean_bit_counts` only when far-end signal has something to
+    // contribute. If `far_bit_counts` is zero the far-end signal is weak and
+    // we likely have a poor echo condition, hence don't update.
+    if (self->farend->far_bit_counts[i] > 0) {
+      // Make number of right shifts piecewise linear w.r.t. `far_bit_counts`.
+      int shifts = kShiftsAtZero;
+      shifts -= (kShiftsLinearSlope * self->farend->far_bit_counts[i]) >> 4;
+      WebRtc_MeanEstimatorFix(bit_count, shifts, &(self->mean_bit_counts[i]));
+    }
+  }
+
+  // Find `candidate_delay`, `value_best_candidate` and `value_worst_candidate`
+  // of `mean_bit_counts`.
+  for (i = 0; i < self->history_size; i++) {
+    if (self->mean_bit_counts[i] < value_best_candidate) {
+      value_best_candidate = self->mean_bit_counts[i];
+      candidate_delay = i;
+    }
+    if (self->mean_bit_counts[i] > value_worst_candidate) {
+      value_worst_candidate = self->mean_bit_counts[i];
+    }
+  }
+  valley_depth = value_worst_candidate - value_best_candidate;
+
+  // The `value_best_candidate` is a good indicator on the probability of
+  // `candidate_delay` being an accurate delay (a small `value_best_candidate`
+  // means a good binary match). In the following sections we make a decision
+  // whether to update `last_delay` or not.
+  // 1) If the difference bit counts between the best and the worst delay
+  //    candidates is too small we consider the situation to be unreliable and
+  //    don't update `last_delay`.
+  // 2) If the situation is reliable we update `last_delay` if the value of the
+  //    best candidate delay has a value less than
+  //     i) an adaptive threshold `minimum_probability`, or
+  //    ii) this corresponding value `last_delay_probability`, but updated at
+  //        this time instant.
+
+  // Update `minimum_probability`.
+  if ((self->minimum_probability > kProbabilityLowerLimit) &&
+      (valley_depth > kProbabilityMinSpread)) {
+    // The "hard" threshold can't be lower than 17 (in Q9).
+    // The valley in the curve also has to be distinct, i.e., the
+    // difference between `value_worst_candidate` and `value_best_candidate` has
+    // to be large enough.
+    int32_t threshold = value_best_candidate + kProbabilityOffset;
+    if (threshold < kProbabilityLowerLimit) {
+      threshold = kProbabilityLowerLimit;
+    }
+    if (self->minimum_probability > threshold) {
+      self->minimum_probability = threshold;
+    }
+  }
+  // Update `last_delay_probability`.
+  // We use a Markov type model, i.e., a slowly increasing level over time.
+  self->last_delay_probability++;
+  // Validate `candidate_delay`.  We have a reliable instantaneous delay
+  // estimate if
+  //  1) The valley is distinct enough (`valley_depth` > `kProbabilityOffset`)
+  // and
+  //  2) The depth of the valley is deep enough
+  //      (`value_best_candidate` < `minimum_probability`)
+  //     and deeper than the best estimate so far
+  //      (`value_best_candidate` < `last_delay_probability`)
+  valid_candidate = ((valley_depth > kProbabilityOffset) &&
+                     ((value_best_candidate < self->minimum_probability) ||
+                      (value_best_candidate < self->last_delay_probability)));
+
+  // Check for nonstationary farend signal.
+  const bool non_stationary_farend =
+      std::any_of(self->farend->far_bit_counts,
+                  self->farend->far_bit_counts + self->history_size,
+                  [](int a) { return a > 0; });
+
+  if (non_stationary_farend) {
+    // Only update the validation statistics when the farend is nonstationary
+    // as the underlying estimates are otherwise frozen.
+    UpdateRobustValidationStatistics(self, candidate_delay, valley_depth,
+                                     value_best_candidate);
+  }
+
+  if (self->robust_validation_enabled) {
+    int is_histogram_valid = HistogramBasedValidation(self, candidate_delay);
+    valid_candidate = RobustValidation(self, candidate_delay, valid_candidate,
+                                       is_histogram_valid);
+  }
+
+  // Only update the delay estimate when the farend is nonstationary and when
+  // a valid delay candidate is available.
+  if (non_stationary_farend && valid_candidate) {
+    if (candidate_delay != self->last_delay) {
+      self->last_delay_histogram =
+          (self->histogram[candidate_delay] > kLastHistogramMax
+               ? kLastHistogramMax
+               : self->histogram[candidate_delay]);
+      // Adjust the histogram if we made a change to `last_delay`, though it was
+      // not the most likely one according to the histogram.
+      if (self->histogram[candidate_delay] <
+          self->histogram[self->compare_delay]) {
+        self->histogram[self->compare_delay] = self->histogram[candidate_delay];
+      }
+    }
+    self->last_delay = candidate_delay;
+    if (value_best_candidate < self->last_delay_probability) {
+      self->last_delay_probability = value_best_candidate;
+    }
+    self->compare_delay = self->last_delay;
+  }
+
+  return self->last_delay;
+}
+
+int WebRtc_binary_last_delay(BinaryDelayEstimator* self) {
+  RTC_DCHECK(self);
+  return self->last_delay;
+}
+
+float WebRtc_binary_last_delay_quality(BinaryDelayEstimator* self) {
+  float quality = 0;
+  RTC_DCHECK(self);
+
+  if (self->robust_validation_enabled) {
+    // Simply a linear function of the histogram height at delay estimate.
+    quality = self->histogram[self->compare_delay] / kHistogramMax;
+  } else {
+    // Note that `last_delay_probability` states how deep the minimum of the
+    // cost function is, so it is rather an error probability.
+    quality = (float)(kMaxBitCountsQ9 - self->last_delay_probability) /
+              kMaxBitCountsQ9;
+    if (quality < 0) {
+      quality = 0;
+    }
+  }
+  return quality;
+}
+
+void WebRtc_MeanEstimatorFix(int32_t new_value,
+                             int factor,
+                             int32_t* mean_value) {
+  int32_t diff = new_value - *mean_value;
+
+  // mean_new = mean_value + ((new_value - mean_value) >> factor);
+  if (diff < 0) {
+    diff = -((-diff) >> factor);
+  } else {
+    diff = (diff >> factor);
+  }
+  *mean_value += diff;
+}
+
+}  // namespace webrtc

VocieProcess/modules/audio_processing/utility/delay_estimator.h

@@ -0,0 +1,257 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+// Performs delay estimation on binary converted spectra.
+// The return value is  0 - OK and -1 - Error, unless otherwise stated.
+
+#ifndef MODULES_AUDIO_PROCESSING_UTILITY_DELAY_ESTIMATOR_H_
+#define MODULES_AUDIO_PROCESSING_UTILITY_DELAY_ESTIMATOR_H_
+
+#include <stdint.h>
+
+namespace webrtc {
+
+static const int32_t kMaxBitCountsQ9 = (32 << 9);  // 32 matching bits in Q9.
+
+typedef struct {
+  // Pointer to bit counts.
+  int* far_bit_counts;
+  // Binary history variables.
+  uint32_t* binary_far_history;
+  int history_size;
+} BinaryDelayEstimatorFarend;
+
+typedef struct {
+  // Pointer to bit counts.
+  int32_t* mean_bit_counts;
+  // Array only used locally in ProcessBinarySpectrum() but whose size is
+  // determined at run-time.
+  int32_t* bit_counts;
+
+  // Binary history variables.
+  uint32_t* binary_near_history;
+  int near_history_size;
+  int history_size;
+
+  // Delay estimation variables.
+  int32_t minimum_probability;
+  int last_delay_probability;
+
+  // Delay memory.
+  int last_delay;
+
+  // Robust validation
+  int robust_validation_enabled;
+  int allowed_offset;
+  int last_candidate_delay;
+  int compare_delay;
+  int candidate_hits;
+  float* histogram;
+  float last_delay_histogram;
+
+  // For dynamically changing the lookahead when using SoftReset...().
+  int lookahead;
+
+  // Far-end binary spectrum history buffer etc.
+  BinaryDelayEstimatorFarend* farend;
+} BinaryDelayEstimator;
+
+// Releases the memory allocated by
+// WebRtc_CreateBinaryDelayEstimatorFarend(...).
+// Input:
+//    - self              : Pointer to the binary delay estimation far-end
+//                          instance which is the return value of
+//                          WebRtc_CreateBinaryDelayEstimatorFarend().
+//
+void WebRtc_FreeBinaryDelayEstimatorFarend(BinaryDelayEstimatorFarend* self);
+
+// Allocates the memory needed by the far-end part of the binary delay
+// estimation. The memory needs to be initialized separately through
+// WebRtc_InitBinaryDelayEstimatorFarend(...).
+//
+// Inputs:
+//      - history_size    : Size of the far-end binary spectrum history.
+//
+// Return value:
+//      - BinaryDelayEstimatorFarend*
+//                        : Created `handle`. If the memory can't be allocated
+//                          or if any of the input parameters are invalid NULL
+//                          is returned.
+//
+BinaryDelayEstimatorFarend* WebRtc_CreateBinaryDelayEstimatorFarend(
+    int history_size);
+
+// Re-allocates the buffers.
+//
+// Inputs:
+//      - self            : Pointer to the binary estimation far-end instance
+//                          which is the return value of
+//                          WebRtc_CreateBinaryDelayEstimatorFarend().
+//      - history_size    : Size of the far-end binary spectrum history.
+//
+// Return value:
+//      - history_size    : The history size allocated.
+int WebRtc_AllocateFarendBufferMemory(BinaryDelayEstimatorFarend* self,
+                                      int history_size);
+
+// Initializes the delay estimation far-end instance created with
+// WebRtc_CreateBinaryDelayEstimatorFarend(...).
+//
+// Input:
+//    - self              : Pointer to the delay estimation far-end instance.
+//
+// Output:
+//    - self              : Initialized far-end instance.
+//
+void WebRtc_InitBinaryDelayEstimatorFarend(BinaryDelayEstimatorFarend* self);
+
+// Soft resets the delay estimation far-end instance created with
+// WebRtc_CreateBinaryDelayEstimatorFarend(...).
+//
+// Input:
+//    - delay_shift   : The amount of blocks to shift history buffers.
+//
+void WebRtc_SoftResetBinaryDelayEstimatorFarend(
+    BinaryDelayEstimatorFarend* self,
+    int delay_shift);
+
+// Adds the binary far-end spectrum to the internal far-end history buffer. This
+// spectrum is used as reference when calculating the delay using
+// WebRtc_ProcessBinarySpectrum().
+//
+// Inputs:
+//    - self                  : Pointer to the delay estimation far-end
+//                              instance.
+//    - binary_far_spectrum   : Far-end binary spectrum.
+//
+// Output:
+//    - self                  : Updated far-end instance.
+//
+void WebRtc_AddBinaryFarSpectrum(BinaryDelayEstimatorFarend* self,
+                                 uint32_t binary_far_spectrum);
+
+// Releases the memory allocated by WebRtc_CreateBinaryDelayEstimator(...).
+//
+// Note that BinaryDelayEstimator utilizes BinaryDelayEstimatorFarend, but does
+// not take ownership of it, hence the BinaryDelayEstimator has to be torn down
+// before the far-end.
+//
+// Input:
+//    - self              : Pointer to the binary delay estimation instance
+//                          which is the return value of
+//                          WebRtc_CreateBinaryDelayEstimator().
+//
+void WebRtc_FreeBinaryDelayEstimator(BinaryDelayEstimator* self);
+
+// Allocates the memory needed by the binary delay estimation. The memory needs
+// to be initialized separately through WebRtc_InitBinaryDelayEstimator(...).
+//
+// See WebRtc_CreateDelayEstimator(..) in delay_estimator_wrapper.c for detailed
+// description.
+BinaryDelayEstimator* WebRtc_CreateBinaryDelayEstimator(
+    BinaryDelayEstimatorFarend* farend,
+    int max_lookahead);
+
+// Re-allocates `history_size` dependent buffers. The far-end buffers will be
+// updated at the same time if needed.
+//
+// Input:
+//      - self            : Pointer to the binary estimation instance which is
+//                          the return value of
+//                          WebRtc_CreateBinaryDelayEstimator().
+//      - history_size    : Size of the history buffers.
+//
+// Return value:
+//      - history_size    : The history size allocated.
+int WebRtc_AllocateHistoryBufferMemory(BinaryDelayEstimator* self,
+                                       int history_size);
+
+// Initializes the delay estimation instance created with
+// WebRtc_CreateBinaryDelayEstimator(...).
+//
+// Input:
+//    - self              : Pointer to the delay estimation instance.
+//
+// Output:
+//    - self              : Initialized instance.
+//
+void WebRtc_InitBinaryDelayEstimator(BinaryDelayEstimator* self);
+
+// Soft resets the delay estimation instance created with
+// WebRtc_CreateBinaryDelayEstimator(...).
+//
+// Input:
+//    - delay_shift   : The amount of blocks to shift history buffers.
+//
+// Return value:
+//    - actual_shifts : The actual number of shifts performed.
+//
+int WebRtc_SoftResetBinaryDelayEstimator(BinaryDelayEstimator* self,
+                                         int delay_shift);
+
+// Estimates and returns the delay between the binary far-end and binary near-
+// end spectra. It is assumed the binary far-end spectrum has been added using
+// WebRtc_AddBinaryFarSpectrum() prior to this call. The value will be offset by
+// the lookahead (i.e. the lookahead should be subtracted from the returned
+// value).
+//
+// Inputs:
+//    - self                  : Pointer to the delay estimation instance.
+//    - binary_near_spectrum  : Near-end binary spectrum of the current block.
+//
+// Output:
+//    - self                  : Updated instance.
+//
+// Return value:
+//    - delay                 :  >= 0 - Calculated delay value.
+//                              -2    - Insufficient data for estimation.
+//
+int WebRtc_ProcessBinarySpectrum(BinaryDelayEstimator* self,
+                                 uint32_t binary_near_spectrum);
+
+// Returns the last calculated delay updated by the function
+// WebRtc_ProcessBinarySpectrum(...).
+//
+// Input:
+//    - self                  : Pointer to the delay estimation instance.
+//
+// Return value:
+//    - delay                 :  >= 0 - Last calculated delay value
+//                              -2    - Insufficient data for estimation.
+//
+int WebRtc_binary_last_delay(BinaryDelayEstimator* self);
+
+// Returns the estimation quality of the last calculated delay updated by the
+// function WebRtc_ProcessBinarySpectrum(...). The estimation quality is a value
+// in the interval [0, 1].  The higher the value, the better the quality.
+//
+// Return value:
+//    - delay_quality         :  >= 0 - Estimation quality of last calculated
+//                                      delay value.
+float WebRtc_binary_last_delay_quality(BinaryDelayEstimator* self);
+
+// Updates the `mean_value` recursively with a step size of 2^-`factor`. This
+// function is used internally in the Binary Delay Estimator as well as the
+// Fixed point wrapper.
+//
+// Inputs:
+//    - new_value             : The new value the mean should be updated with.
+//    - factor                : The step size, in number of right shifts.
+//
+// Input/Output:
+//    - mean_value            : Pointer to the mean value.
+//
+void WebRtc_MeanEstimatorFix(int32_t new_value,
+                             int factor,
+                             int32_t* mean_value);
+
+}  // namespace webrtc
+
+#endif  // MODULES_AUDIO_PROCESSING_UTILITY_DELAY_ESTIMATOR_H_

VocieProcess/modules/audio_processing/utility/delay_estimator_internal.h

@@ -0,0 +1,51 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+// Header file including the delay estimator handle used for testing.
+
+#ifndef MODULES_AUDIO_PROCESSING_UTILITY_DELAY_ESTIMATOR_INTERNAL_H_
+#define MODULES_AUDIO_PROCESSING_UTILITY_DELAY_ESTIMATOR_INTERNAL_H_
+
+#include "modules/audio_processing/utility/delay_estimator.h"
+
+namespace webrtc {
+
+typedef union {
+  float float_;
+  int32_t int32_;
+} SpectrumType;
+
+typedef struct {
+  // Pointers to mean values of spectrum.
+  SpectrumType* mean_far_spectrum;
+  // `mean_far_spectrum` initialization indicator.
+  int far_spectrum_initialized;
+
+  int spectrum_size;
+
+  // Far-end part of binary spectrum based delay estimation.
+  BinaryDelayEstimatorFarend* binary_farend;
+} DelayEstimatorFarend;
+
+typedef struct {
+  // Pointers to mean values of spectrum.
+  SpectrumType* mean_near_spectrum;
+  // `mean_near_spectrum` initialization indicator.
+  int near_spectrum_initialized;
+
+  int spectrum_size;
+
+  // Binary spectrum based delay estimator
+  BinaryDelayEstimator* binary_handle;
+} DelayEstimator;
+
+}  // namespace webrtc
+
+#endif  // MODULES_AUDIO_PROCESSING_UTILITY_DELAY_ESTIMATOR_INTERNAL_H_

VocieProcess/modules/audio_processing/utility/delay_estimator_wrapper.cc

@@ -0,0 +1,489 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "modules/audio_processing/utility/delay_estimator_wrapper.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "modules/audio_processing/utility/delay_estimator.h"
+#include "modules/audio_processing/utility/delay_estimator_internal.h"
+#include "rtc_base/checks.h"
+
+namespace webrtc {
+
+// Only bit `kBandFirst` through bit `kBandLast` are processed and
+// `kBandFirst` - `kBandLast` must be < 32.
+constexpr int kBandFirst = 12;
+constexpr int kBandLast = 43;
+
+static __inline uint32_t SetBit(uint32_t in, int pos) {
+  uint32_t mask = (1 << pos);
+  uint32_t out = (in | mask);
+
+  return out;
+}
+
+// Calculates the mean recursively. Same version as WebRtc_MeanEstimatorFix(),
+// but for float.
+//
+// Inputs:
+//    - new_value             : New additional value.
+//    - scale                 : Scale for smoothing (should be less than 1.0).
+//
+// Input/Output:
+//    - mean_value            : Pointer to the mean value for updating.
+//
+static void MeanEstimatorFloat(float new_value,
+                               float scale,
+                               float* mean_value) {
+  RTC_DCHECK_LT(scale, 1.0f);
+  *mean_value += (new_value - *mean_value) * scale;
+}
+
+// Computes the binary spectrum by comparing the input `spectrum` with a
+// `threshold_spectrum`. Float and fixed point versions.
+//
+// Inputs:
+//      - spectrum            : Spectrum of which the binary spectrum should be
+//                              calculated.
+//      - threshold_spectrum  : Threshold spectrum with which the input
+//                              spectrum is compared.
+// Return:
+//      - out                 : Binary spectrum.
+//
+static uint32_t BinarySpectrumFix(const uint16_t* spectrum,
+                                  SpectrumType* threshold_spectrum,
+                                  int q_domain,
+                                  int* threshold_initialized) {
+  int i = kBandFirst;
+  uint32_t out = 0;
+
+  RTC_DCHECK_LT(q_domain, 16);
+
+  if (!(*threshold_initialized)) {
+    // Set the `threshold_spectrum` to half the input `spectrum` as starting
+    // value. This speeds up the convergence.
+    for (i = kBandFirst; i <= kBandLast; i++) {
+      if (spectrum[i] > 0) {
+        // Convert input spectrum from Q(`q_domain`) to Q15.
+        int32_t spectrum_q15 = ((int32_t)spectrum[i]) << (15 - q_domain);
+        threshold_spectrum[i].int32_ = (spectrum_q15 >> 1);
+        *threshold_initialized = 1;
+      }
+    }
+  }
+  for (i = kBandFirst; i <= kBandLast; i++) {
+    // Convert input spectrum from Q(`q_domain`) to Q15.
+    int32_t spectrum_q15 = ((int32_t)spectrum[i]) << (15 - q_domain);
+    // Update the `threshold_spectrum`.
+    WebRtc_MeanEstimatorFix(spectrum_q15, 6, &(threshold_spectrum[i].int32_));
+    // Convert `spectrum` at current frequency bin to a binary value.
+    if (spectrum_q15 > threshold_spectrum[i].int32_) {
+      out = SetBit(out, i - kBandFirst);
+    }
+  }
+
+  return out;
+}
+
+static uint32_t BinarySpectrumFloat(const float* spectrum,
+                                    SpectrumType* threshold_spectrum,
+                                    int* threshold_initialized) {
+  int i = kBandFirst;
+  uint32_t out = 0;
+  const float kScale = 1 / 64.0;
+
+  if (!(*threshold_initialized)) {
+    // Set the `threshold_spectrum` to half the input `spectrum` as starting
+    // value. This speeds up the convergence.
+    for (i = kBandFirst; i <= kBandLast; i++) {
+      if (spectrum[i] > 0.0f) {
+        threshold_spectrum[i].float_ = (spectrum[i] / 2);
+        *threshold_initialized = 1;
+      }
+    }
+  }
+
+  for (i = kBandFirst; i <= kBandLast; i++) {
+    // Update the `threshold_spectrum`.
+    MeanEstimatorFloat(spectrum[i], kScale, &(threshold_spectrum[i].float_));
+    // Convert `spectrum` at current frequency bin to a binary value.
+    if (spectrum[i] > threshold_spectrum[i].float_) {
+      out = SetBit(out, i - kBandFirst);
+    }
+  }
+
+  return out;
+}
+
+void WebRtc_FreeDelayEstimatorFarend(void* handle) {
+  DelayEstimatorFarend* self = (DelayEstimatorFarend*)handle;
+
+  if (handle == NULL) {
+    return;
+  }
+
+  free(self->mean_far_spectrum);
+  self->mean_far_spectrum = NULL;
+
+  WebRtc_FreeBinaryDelayEstimatorFarend(self->binary_farend);
+  self->binary_farend = NULL;
+
+  free(self);
+}
+
+void* WebRtc_CreateDelayEstimatorFarend(int spectrum_size, int history_size) {
+  DelayEstimatorFarend* self = NULL;
+
+  // Check if the sub band used in the delay estimation is small enough to fit
+  // the binary spectra in a uint32_t.
+  static_assert(kBandLast - kBandFirst < 32, "");
+
+  if (spectrum_size >= kBandLast) {
+    self = static_cast<DelayEstimatorFarend*>(
+        malloc(sizeof(DelayEstimatorFarend)));
+  }
+
+  if (self != NULL) {
+    int memory_fail = 0;
+
+    // Allocate memory for the binary far-end spectrum handling.
+    self->binary_farend = WebRtc_CreateBinaryDelayEstimatorFarend(history_size);
+    memory_fail |= (self->binary_farend == NULL);
+
+    // Allocate memory for spectrum buffers.
+    self->mean_far_spectrum = static_cast<SpectrumType*>(
+        malloc(spectrum_size * sizeof(SpectrumType)));
+    memory_fail |= (self->mean_far_spectrum == NULL);
+
+    self->spectrum_size = spectrum_size;
+
+    if (memory_fail) {
+      WebRtc_FreeDelayEstimatorFarend(self);
+      self = NULL;
+    }
+  }
+
+  return self;
+}
+
+int WebRtc_InitDelayEstimatorFarend(void* handle) {
+  DelayEstimatorFarend* self = (DelayEstimatorFarend*)handle;
+
+  if (self == NULL) {
+    return -1;
+  }
+
+  // Initialize far-end part of binary delay estimator.
+  WebRtc_InitBinaryDelayEstimatorFarend(self->binary_farend);
+
+  // Set averaged far and near end spectra to zero.
+  memset(self->mean_far_spectrum, 0,
+         sizeof(SpectrumType) * self->spectrum_size);
+  // Reset initialization indicators.
+  self->far_spectrum_initialized = 0;
+
+  return 0;
+}
+
+void WebRtc_SoftResetDelayEstimatorFarend(void* handle, int delay_shift) {
+  DelayEstimatorFarend* self = (DelayEstimatorFarend*)handle;
+  RTC_DCHECK(self);
+  WebRtc_SoftResetBinaryDelayEstimatorFarend(self->binary_farend, delay_shift);
+}
+
+int WebRtc_AddFarSpectrumFix(void* handle,
+                             const uint16_t* far_spectrum,
+                             int spectrum_size,
+                             int far_q) {
+  DelayEstimatorFarend* self = (DelayEstimatorFarend*)handle;
+  uint32_t binary_spectrum = 0;
+
+  if (self == NULL) {
+    return -1;
+  }
+  if (far_spectrum == NULL) {
+    // Empty far end spectrum.
+    return -1;
+  }
+  if (spectrum_size != self->spectrum_size) {
+    // Data sizes don't match.
+    return -1;
+  }
+  if (far_q > 15) {
+    // If `far_q` is larger than 15 we cannot guarantee no wrap around.
+    return -1;
+  }
+
+  // Get binary spectrum.
+  binary_spectrum = BinarySpectrumFix(far_spectrum, self->mean_far_spectrum,
+                                      far_q, &(self->far_spectrum_initialized));
+  WebRtc_AddBinaryFarSpectrum(self->binary_farend, binary_spectrum);
+
+  return 0;
+}
+
+int WebRtc_AddFarSpectrumFloat(void* handle,
+                               const float* far_spectrum,
+                               int spectrum_size) {
+  DelayEstimatorFarend* self = (DelayEstimatorFarend*)handle;
+  uint32_t binary_spectrum = 0;
+
+  if (self == NULL) {
+    return -1;
+  }
+  if (far_spectrum == NULL) {
+    // Empty far end spectrum.
+    return -1;
+  }
+  if (spectrum_size != self->spectrum_size) {
+    // Data sizes don't match.
+    return -1;
+  }
+
+  // Get binary spectrum.
+  binary_spectrum = BinarySpectrumFloat(far_spectrum, self->mean_far_spectrum,
+                                        &(self->far_spectrum_initialized));
+  WebRtc_AddBinaryFarSpectrum(self->binary_farend, binary_spectrum);
+
+  return 0;
+}
+
+void WebRtc_FreeDelayEstimator(void* handle) {
+  DelayEstimator* self = (DelayEstimator*)handle;
+
+  if (handle == NULL) {
+    return;
+  }
+
+  free(self->mean_near_spectrum);
+  self->mean_near_spectrum = NULL;
+
+  WebRtc_FreeBinaryDelayEstimator(self->binary_handle);
+  self->binary_handle = NULL;
+
+  free(self);
+}
+
+void* WebRtc_CreateDelayEstimator(void* farend_handle, int max_lookahead) {
+  DelayEstimator* self = NULL;
+  DelayEstimatorFarend* farend = (DelayEstimatorFarend*)farend_handle;
+
+  if (farend_handle != NULL) {
+    self = static_cast<DelayEstimator*>(malloc(sizeof(DelayEstimator)));
+  }
+
+  if (self != NULL) {
+    int memory_fail = 0;
+
+    // Allocate memory for the farend spectrum handling.
+    self->binary_handle =
+        WebRtc_CreateBinaryDelayEstimator(farend->binary_farend, max_lookahead);
+    memory_fail |= (self->binary_handle == NULL);
+
+    // Allocate memory for spectrum buffers.
+    self->mean_near_spectrum = static_cast<SpectrumType*>(
+        malloc(farend->spectrum_size * sizeof(SpectrumType)));
+    memory_fail |= (self->mean_near_spectrum == NULL);
+
+    self->spectrum_size = farend->spectrum_size;
+
+    if (memory_fail) {
+      WebRtc_FreeDelayEstimator(self);
+      self = NULL;
+    }
+  }
+
+  return self;
+}
+
+int WebRtc_InitDelayEstimator(void* handle) {
+  DelayEstimator* self = (DelayEstimator*)handle;
+
+  if (self == NULL) {
+    return -1;
+  }
+
+  // Initialize binary delay estimator.
+  WebRtc_InitBinaryDelayEstimator(self->binary_handle);
+
+  // Set averaged far and near end spectra to zero.
+  memset(self->mean_near_spectrum, 0,
+         sizeof(SpectrumType) * self->spectrum_size);
+  // Reset initialization indicators.
+  self->near_spectrum_initialized = 0;
+
+  return 0;
+}
+
+int WebRtc_SoftResetDelayEstimator(void* handle, int delay_shift) {
+  DelayEstimator* self = (DelayEstimator*)handle;
+  RTC_DCHECK(self);
+  return WebRtc_SoftResetBinaryDelayEstimator(self->binary_handle, delay_shift);
+}
+
+int WebRtc_set_history_size(void* handle, int history_size) {
+  DelayEstimator* self = static_cast<DelayEstimator*>(handle);
+
+  if ((self == NULL) || (history_size <= 1)) {
+    return -1;
+  }
+  return WebRtc_AllocateHistoryBufferMemory(self->binary_handle, history_size);
+}
+
+int WebRtc_history_size(const void* handle) {
+  const DelayEstimator* self = static_cast<const DelayEstimator*>(handle);
+
+  if (self == NULL) {
+    return -1;
+  }
+  if (self->binary_handle->farend->history_size !=
+      self->binary_handle->history_size) {
+    // Non matching history sizes.
+    return -1;
+  }
+  return self->binary_handle->history_size;
+}
+
+int WebRtc_set_lookahead(void* handle, int lookahead) {
+  DelayEstimator* self = (DelayEstimator*)handle;
+  RTC_DCHECK(self);
+  RTC_DCHECK(self->binary_handle);
+  if ((lookahead > self->binary_handle->near_history_size - 1) ||
+      (lookahead < 0)) {
+    return -1;
+  }
+  self->binary_handle->lookahead = lookahead;
+  return self->binary_handle->lookahead;
+}
+
+int WebRtc_lookahead(void* handle) {
+  DelayEstimator* self = (DelayEstimator*)handle;
+  RTC_DCHECK(self);
+  RTC_DCHECK(self->binary_handle);
+  return self->binary_handle->lookahead;
+}
+
+int WebRtc_set_allowed_offset(void* handle, int allowed_offset) {
+  DelayEstimator* self = (DelayEstimator*)handle;
+
+  if ((self == NULL) || (allowed_offset < 0)) {
+    return -1;
+  }
+  self->binary_handle->allowed_offset = allowed_offset;
+  return 0;
+}
+
+int WebRtc_get_allowed_offset(const void* handle) {
+  const DelayEstimator* self = (const DelayEstimator*)handle;
+
+  if (self == NULL) {
+    return -1;
+  }
+  return self->binary_handle->allowed_offset;
+}
+
+int WebRtc_enable_robust_validation(void* handle, int enable) {
+  DelayEstimator* self = (DelayEstimator*)handle;
+
+  if (self == NULL) {
+    return -1;
+  }
+  if ((enable < 0) || (enable > 1)) {
+    return -1;
+  }
+  RTC_DCHECK(self->binary_handle);
+  self->binary_handle->robust_validation_enabled = enable;
+  return 0;
+}
+
+int WebRtc_is_robust_validation_enabled(const void* handle) {
+  const DelayEstimator* self = (const DelayEstimator*)handle;
+
+  if (self == NULL) {
+    return -1;
+  }
+  return self->binary_handle->robust_validation_enabled;
+}
+
+int WebRtc_DelayEstimatorProcessFix(void* handle,
+                                    const uint16_t* near_spectrum,
+                                    int spectrum_size,
+                                    int near_q) {
+  DelayEstimator* self = (DelayEstimator*)handle;
+  uint32_t binary_spectrum = 0;
+
+  if (self == NULL) {
+    return -1;
+  }
+  if (near_spectrum == NULL) {
+    // Empty near end spectrum.
+    return -1;
+  }
+  if (spectrum_size != self->spectrum_size) {
+    // Data sizes don't match.
+    return -1;
+  }
+  if (near_q > 15) {
+    // If `near_q` is larger than 15 we cannot guarantee no wrap around.
+    return -1;
+  }
+
+  // Get binary spectra.
+  binary_spectrum =
+      BinarySpectrumFix(near_spectrum, self->mean_near_spectrum, near_q,
+                        &(self->near_spectrum_initialized));
+
+  return WebRtc_ProcessBinarySpectrum(self->binary_handle, binary_spectrum);
+}
+
+int WebRtc_DelayEstimatorProcessFloat(void* handle,
+                                      const float* near_spectrum,
+                                      int spectrum_size) {
+  DelayEstimator* self = (DelayEstimator*)handle;
+  uint32_t binary_spectrum = 0;
+
+  if (self == NULL) {
+    return -1;
+  }
+  if (near_spectrum == NULL) {
+    // Empty near end spectrum.
+    return -1;
+  }
+  if (spectrum_size != self->spectrum_size) {
+    // Data sizes don't match.
+    return -1;
+  }
+
+  // Get binary spectrum.
+  binary_spectrum = BinarySpectrumFloat(near_spectrum, self->mean_near_spectrum,
+                                        &(self->near_spectrum_initialized));
+
+  return WebRtc_ProcessBinarySpectrum(self->binary_handle, binary_spectrum);
+}
+
+int WebRtc_last_delay(void* handle) {
+  DelayEstimator* self = (DelayEstimator*)handle;
+
+  if (self == NULL) {
+    return -1;
+  }
+
+  return WebRtc_binary_last_delay(self->binary_handle);
+}
+
+float WebRtc_last_delay_quality(void* handle) {
+  DelayEstimator* self = (DelayEstimator*)handle;
+  RTC_DCHECK(self);
+  return WebRtc_binary_last_delay_quality(self->binary_handle);
+}
+
+}  // namespace webrtc

VocieProcess/modules/audio_processing/utility/delay_estimator_wrapper.h

@@ -0,0 +1,248 @@
+/*
+ *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+// Performs delay estimation on block by block basis.
+// The return value is  0 - OK and -1 - Error, unless otherwise stated.
+
+#ifndef MODULES_AUDIO_PROCESSING_UTILITY_DELAY_ESTIMATOR_WRAPPER_H_
+#define MODULES_AUDIO_PROCESSING_UTILITY_DELAY_ESTIMATOR_WRAPPER_H_
+
+#include <stdint.h>
+
+namespace webrtc {
+
+// Releases the memory allocated by WebRtc_CreateDelayEstimatorFarend(...)
+void WebRtc_FreeDelayEstimatorFarend(void* handle);
+
+// Allocates the memory needed by the far-end part of the delay estimation. The
+// memory needs to be initialized separately through
+// WebRtc_InitDelayEstimatorFarend(...).
+//
+// Inputs:
+//  - spectrum_size     : Size of the spectrum used both in far-end and
+//                        near-end. Used to allocate memory for spectrum
+//                        specific buffers.
+//  - history_size      : The far-end history buffer size. A change in buffer
+//                        size can be forced with WebRtc_set_history_size().
+//                        Note that the maximum delay which can be estimated is
+//                        determined together with WebRtc_set_lookahead().
+//
+// Return value:
+//  - void*             : Created `handle`. If the memory can't be allocated or
+//                        if any of the input parameters are invalid NULL is
+//                        returned.
+void* WebRtc_CreateDelayEstimatorFarend(int spectrum_size, int history_size);
+
+// Initializes the far-end part of the delay estimation instance returned by
+// WebRtc_CreateDelayEstimatorFarend(...)
+int WebRtc_InitDelayEstimatorFarend(void* handle);
+
+// Soft resets the far-end part of the delay estimation instance returned by
+// WebRtc_CreateDelayEstimatorFarend(...).
+// Input:
+//      - delay_shift   : The amount of blocks to shift history buffers.
+void WebRtc_SoftResetDelayEstimatorFarend(void* handle, int delay_shift);
+
+// Adds the far-end spectrum to the far-end history buffer. This spectrum is
+// used as reference when calculating the delay using
+// WebRtc_ProcessSpectrum().
+//
+// Inputs:
+//    - far_spectrum    : Far-end spectrum.
+//    - spectrum_size   : The size of the data arrays (same for both far- and
+//                        near-end).
+//    - far_q           : The Q-domain of the far-end data.
+//
+// Output:
+//    - handle          : Updated far-end instance.
+//
+int WebRtc_AddFarSpectrumFix(void* handle,
+                             const uint16_t* far_spectrum,
+                             int spectrum_size,
+                             int far_q);
+
+// See WebRtc_AddFarSpectrumFix() for description.
+int WebRtc_AddFarSpectrumFloat(void* handle,
+                               const float* far_spectrum,
+                               int spectrum_size);
+
+// Releases the memory allocated by WebRtc_CreateDelayEstimator(...)
+void WebRtc_FreeDelayEstimator(void* handle);
+
+// Allocates the memory needed by the delay estimation. The memory needs to be
+// initialized separately through WebRtc_InitDelayEstimator(...).
+//
+// Inputs:
+//      - farend_handle : Pointer to the far-end part of the delay estimation
+//                        instance created prior to this call using
+//                        WebRtc_CreateDelayEstimatorFarend().
+//
+//                        Note that WebRtc_CreateDelayEstimator does not take
+//                        ownership of `farend_handle`, which has to be torn
+//                        down properly after this instance.
+//
+//      - max_lookahead : Maximum amount of non-causal lookahead allowed. The
+//                        actual amount of lookahead used can be controlled by
+//                        WebRtc_set_lookahead(...). The default `lookahead` is
+//                        set to `max_lookahead` at create time. Use
+//                        WebRtc_set_lookahead(...) before start if a different
+//                        value is desired.
+//
+//                        Using lookahead can detect cases in which a near-end
+//                        signal occurs before the corresponding far-end signal.
+//                        It will delay the estimate for the current block by an
+//                        equal amount, and the returned values will be offset
+//                        by it.
+//
+//                        A value of zero is the typical no-lookahead case.
+//                        This also represents the minimum delay which can be
+//                        estimated.
+//
+//                        Note that the effective range of delay estimates is
+//                        [-`lookahead`,... ,`history_size`-`lookahead`)
+//                        where `history_size` is set through
+//                        WebRtc_set_history_size().
+//
+// Return value:
+//      - void*         : Created `handle`. If the memory can't be allocated or
+//                        if any of the input parameters are invalid NULL is
+//                        returned.
+void* WebRtc_CreateDelayEstimator(void* farend_handle, int max_lookahead);
+
+// Initializes the delay estimation instance returned by
+// WebRtc_CreateDelayEstimator(...)
+int WebRtc_InitDelayEstimator(void* handle);
+
+// Soft resets the delay estimation instance returned by
+// WebRtc_CreateDelayEstimator(...)
+// Input:
+//      - delay_shift   : The amount of blocks to shift history buffers.
+//
+// Return value:
+//      - actual_shifts : The actual number of shifts performed.
+int WebRtc_SoftResetDelayEstimator(void* handle, int delay_shift);
+
+// Sets the effective `history_size` used. Valid values from 2. We simply need
+// at least two delays to compare to perform an estimate. If `history_size` is
+// changed, buffers are reallocated filling in with zeros if necessary.
+// Note that changing the `history_size` affects both buffers in far-end and
+// near-end. Hence it is important to change all DelayEstimators that use the
+// same reference far-end, to the same `history_size` value.
+// Inputs:
+//  - handle            : Pointer to the delay estimation instance.
+//  - history_size      : Effective history size to be used.
+// Return value:
+//  - new_history_size  : The new history size used. If the memory was not able
+//                        to be allocated 0 is returned.
+int WebRtc_set_history_size(void* handle, int history_size);
+
+// Returns the history_size currently used.
+// Input:
+//      - handle        : Pointer to the delay estimation instance.
+int WebRtc_history_size(const void* handle);
+
+// Sets the amount of `lookahead` to use. Valid values are [0, max_lookahead]
+// where `max_lookahead` was set at create time through
+// WebRtc_CreateDelayEstimator(...).
+//
+// Input:
+//      - handle        : Pointer to the delay estimation instance.
+//      - lookahead     : The amount of lookahead to be used.
+//
+// Return value:
+//      - new_lookahead : The actual amount of lookahead set, unless `handle` is
+//                        a NULL pointer or `lookahead` is invalid, for which an
+//                        error is returned.
+int WebRtc_set_lookahead(void* handle, int lookahead);
+
+// Returns the amount of lookahead we currently use.
+// Input:
+//      - handle        : Pointer to the delay estimation instance.
+int WebRtc_lookahead(void* handle);
+
+// Sets the `allowed_offset` used in the robust validation scheme.  If the
+// delay estimator is used in an echo control component, this parameter is
+// related to the filter length.  In principle `allowed_offset` should be set to
+// the echo control filter length minus the expected echo duration, i.e., the
+// delay offset the echo control can handle without quality regression.  The
+// default value, used if not set manually, is zero.  Note that `allowed_offset`
+// has to be non-negative.
+// Inputs:
+//  - handle            : Pointer to the delay estimation instance.
+//  - allowed_offset    : The amount of delay offset, measured in partitions,
+//                        the echo control filter can handle.
+int WebRtc_set_allowed_offset(void* handle, int allowed_offset);
+
+// Returns the `allowed_offset` in number of partitions.
+int WebRtc_get_allowed_offset(const void* handle);
+
+// Enables/Disables a robust validation functionality in the delay estimation.
+// This is by default set to disabled at create time.  The state is preserved
+// over a reset.
+// Inputs:
+//      - handle        : Pointer to the delay estimation instance.
+//      - enable        : Enable (1) or disable (0) this feature.
+int WebRtc_enable_robust_validation(void* handle, int enable);
+
+// Returns 1 if robust validation is enabled and 0 if disabled.
+int WebRtc_is_robust_validation_enabled(const void* handle);
+
+// Estimates and returns the delay between the far-end and near-end blocks. The
+// value will be offset by the lookahead (i.e. the lookahead should be
+// subtracted from the returned value).
+// Inputs:
+//      - handle        : Pointer to the delay estimation instance.
+//      - near_spectrum : Pointer to the near-end spectrum data of the current
+//                        block.
+//      - spectrum_size : The size of the data arrays (same for both far- and
+//                        near-end).
+//      - near_q        : The Q-domain of the near-end data.
+//
+// Output:
+//      - handle        : Updated instance.
+//
+// Return value:
+//      - delay         :  >= 0 - Calculated delay value.
+//                        -1    - Error.
+//                        -2    - Insufficient data for estimation.
+int WebRtc_DelayEstimatorProcessFix(void* handle,
+                                    const uint16_t* near_spectrum,
+                                    int spectrum_size,
+                                    int near_q);
+
+// See WebRtc_DelayEstimatorProcessFix() for description.
+int WebRtc_DelayEstimatorProcessFloat(void* handle,
+                                      const float* near_spectrum,
+                                      int spectrum_size);
+
+// Returns the last calculated delay updated by the function
+// WebRtc_DelayEstimatorProcess(...).
+//
+// Input:
+//      - handle        : Pointer to the delay estimation instance.
+//
+// Return value:
+//      - delay         : >= 0  - Last calculated delay value.
+//                        -1    - Error.
+//                        -2    - Insufficient data for estimation.
+int WebRtc_last_delay(void* handle);
+
+// Returns the estimation quality/probability of the last calculated delay
+// updated by the function WebRtc_DelayEstimatorProcess(...). The estimation
+// quality is a value in the interval [0, 1]. The higher the value, the better
+// the quality.
+//
+// Return value:
+//      - delay_quality : >= 0  - Estimation quality of last calculated delay.
+float WebRtc_last_delay_quality(void* handle);
+
+}  // namespace webrtc
+
+#endif  // MODULES_AUDIO_PROCESSING_UTILITY_DELAY_ESTIMATOR_WRAPPER_H_

VocieProcess/rtc_base/sanitizer.h

@@ -0,0 +1,144 @@
+/*
+ *  Copyright 2016 The WebRTC Project Authors. All rights reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef RTC_BASE_SANITIZER_H_
+#define RTC_BASE_SANITIZER_H_
+
+#include <stddef.h>  // For size_t.
+
+#ifdef __cplusplus
+#include "absl/meta/type_traits.h"
+#endif
+
+#if defined(__has_feature)
+#if __has_feature(address_sanitizer)
+#define RTC_HAS_ASAN 1
+#endif
+#if __has_feature(memory_sanitizer)
+#define RTC_HAS_MSAN 1
+#endif
+#endif
+#ifndef RTC_HAS_ASAN
+#define RTC_HAS_ASAN 0
+#endif
+#ifndef RTC_HAS_MSAN
+#define RTC_HAS_MSAN 0
+#endif
+
+#if RTC_HAS_ASAN
+#include <sanitizer/asan_interface.h>
+#endif
+#if RTC_HAS_MSAN
+#include <sanitizer/msan_interface.h>
+#endif
+
+#ifdef __has_attribute
+#if __has_attribute(no_sanitize)
+#define RTC_NO_SANITIZE(what) __attribute__((no_sanitize(what)))
+#endif
+#endif
+#ifndef RTC_NO_SANITIZE
+#define RTC_NO_SANITIZE(what)
+#endif
+
+// Ask ASan to mark the memory range [ptr, ptr + element_size * num_elements)
+// as being unaddressable, so that reads and writes are not allowed. ASan may
+// narrow the range to the nearest alignment boundaries.
+static inline void rtc_AsanPoison(const volatile void* ptr,
+                                  size_t element_size,
+                                  size_t num_elements) {
+#if RTC_HAS_ASAN
+  ASAN_POISON_MEMORY_REGION(ptr, element_size * num_elements);
+#endif
+}
+
+// Ask ASan to mark the memory range [ptr, ptr + element_size * num_elements)
+// as being addressable, so that reads and writes are allowed. ASan may widen
+// the range to the nearest alignment boundaries.
+static inline void rtc_AsanUnpoison(const volatile void* ptr,
+                                    size_t element_size,
+                                    size_t num_elements) {
+#if RTC_HAS_ASAN
+  ASAN_UNPOISON_MEMORY_REGION(ptr, element_size * num_elements);
+#endif
+}
+
+// Ask MSan to mark the memory range [ptr, ptr + element_size * num_elements)
+// as being uninitialized.
+static inline void rtc_MsanMarkUninitialized(const volatile void* ptr,
+                                             size_t element_size,
+                                             size_t num_elements) {
+#if RTC_HAS_MSAN
+  __msan_poison(ptr, element_size * num_elements);
+#endif
+}
+
+// Force an MSan check (if any bits in the memory range [ptr, ptr +
+// element_size * num_elements) are uninitialized the call will crash with an
+// MSan report).
+static inline void rtc_MsanCheckInitialized(const volatile void* ptr,
+                                            size_t element_size,
+                                            size_t num_elements) {
+#if RTC_HAS_MSAN
+  __msan_check_mem_is_initialized(ptr, element_size * num_elements);
+#endif
+}
+
+#ifdef __cplusplus
+
+namespace rtc {
+namespace sanitizer_impl {
+
+template <typename T>
+constexpr bool IsTriviallyCopyable() {
+  return static_cast<bool>(absl::is_trivially_copy_constructible<T>::value &&
+                           (absl::is_trivially_copy_assignable<T>::value ||
+                            !std::is_copy_assignable<T>::value) &&
+                           absl::is_trivially_destructible<T>::value);
+}
+
+}  // namespace sanitizer_impl
+
+template <typename T>
+inline void AsanPoison(const T& mem) {
+  rtc_AsanPoison(mem.data(), sizeof(mem.data()[0]), mem.size());
+}
+
+template <typename T>
+inline void AsanUnpoison(const T& mem) {
+  rtc_AsanUnpoison(mem.data(), sizeof(mem.data()[0]), mem.size());
+}
+
+template <typename T>
+inline void MsanMarkUninitialized(const T& mem) {
+  rtc_MsanMarkUninitialized(mem.data(), sizeof(mem.data()[0]), mem.size());
+}
+
+template <typename T>
+inline T MsanUninitialized(T t) {
+#if RTC_HAS_MSAN
+  // TODO(bugs.webrtc.org/8762): Switch to std::is_trivially_copyable when it
+  // becomes available in downstream projects.
+  static_assert(sanitizer_impl::IsTriviallyCopyable<T>(), "");
+#endif
+  rtc_MsanMarkUninitialized(&t, sizeof(T), 1);
+  return t;
+}
+
+template <typename T>
+inline void MsanCheckInitialized(const T& mem) {
+  rtc_MsanCheckInitialized(mem.data(), sizeof(mem.data()[0]), mem.size());
+}
+
+}  // namespace rtc
+
+#endif  // __cplusplus
+
+#endif  // RTC_BASE_SANITIZER_H_