Older/MediaServer/libflv/source/flv-header.c

334 lines
8.8 KiB
C
Raw Normal View History

2024-10-01 00:12:57 +08:00
#include "flv-header.h"
#include "flv-proto.h"
#include <assert.h>
#include <errno.h>
#define N_TAG_SIZE 4 // previous tag size
#define FLV_HEADER_SIZE 9 // DataOffset included
#define FLV_TAG_HEADER_SIZE 11 // StreamID included
static inline uint32_t be_read_uint32(const uint8_t* ptr)
{
return (ptr[0] << 24) | (ptr[1] << 16) | (ptr[2] << 8) | ptr[3];
}
static inline void be_write_uint32(uint8_t* ptr, uint32_t val)
{
ptr[0] = (uint8_t)((val >> 24) & 0xFF);
ptr[1] = (uint8_t)((val >> 16) & 0xFF);
ptr[2] = (uint8_t)((val >> 8) & 0xFF);
ptr[3] = (uint8_t)(val & 0xFF);
}
int flv_header_read(struct flv_header_t* flv, const uint8_t* buf, size_t len)
{
if (len < FLV_HEADER_SIZE || 'F' != buf[0] || 'L' != buf[1] || 'V' != buf[2])
{
assert(0);
return -1;
}
flv->FLV[0] = buf[0];
flv->FLV[1] = buf[1];
flv->FLV[2] = buf[2];
flv->version = buf[3];
assert(0x00 == (buf[4] & 0xF8) && 0x00 == (buf[4] & 0x20));
flv->audio = (buf[4] >> 2) & 0x01;
flv->video = buf[4] & 0x01;
flv->offset = be_read_uint32(buf + 5);
return FLV_HEADER_SIZE;
}
int flv_tag_header_read(struct flv_tag_header_t* tag, const uint8_t* buf, size_t len)
{
if (len < FLV_TAG_HEADER_SIZE)
{
assert(0);
return -1;
}
// TagType
tag->type = buf[0] & 0x1F;
tag->filter = (buf[0] >> 5) & 0x01;
assert(FLV_TYPE_VIDEO == tag->type || FLV_TYPE_AUDIO == tag->type || FLV_TYPE_SCRIPT == tag->type);
// DataSize
tag->size = ((uint32_t)buf[1] << 16) | ((uint32_t)buf[2] << 8) | buf[3];
// TimestampExtended | Timestamp
tag->timestamp = ((uint32_t)buf[4] << 16) | ((uint32_t)buf[5] << 8) | buf[6] | ((uint32_t)buf[7] << 24);
// StreamID Always 0
tag->streamId = ((uint32_t)buf[8] << 16) | ((uint32_t)buf[9] << 8) | buf[10];
//assert(0 == tag->streamId);
return FLV_TAG_HEADER_SIZE;
}
int flv_audio_tag_header_read(struct flv_audio_tag_header_t* audio, const uint8_t* buf, size_t len)
{
assert(len > 0);
audio->codecid = (buf[0] & 0xF0) /*>> 4*/;
audio->rate = (buf[0] & 0x0C) >> 2;
audio->bits = (buf[0] & 0x02) >> 1;
audio->channels = buf[0] & 0x01;
audio->avpacket = FLV_AVPACKET;
if (FLV_AUDIO_AAC == audio->codecid || FLV_AUDIO_OPUS == audio->codecid)
{
if (len < 2)
{
assert(0);
return -1;
}
audio->avpacket = buf[1];
assert(FLV_SEQUENCE_HEADER == audio->avpacket || FLV_AVPACKET == audio->avpacket);
return 2;
}
else
{
return 1;
}
}
int flv_video_tag_header_read(struct flv_video_tag_header_t* video, const uint8_t* buf, size_t len)
{
assert(len > 0);
if (len >= 5 && 0 != (buf[0] & 0x80))
{
// https://github.com/veovera/enhanced-rtmp/blob/main/enhanced-rtmp.pdf
video->keyframe = (buf[0] & 0x70) >> 4;
video->avpacket = (buf[0] & 0x0F);
video->cts = 0; // default
switch (FLV_VIDEO_FOURCC(buf[1], buf[2], buf[3], buf[4]))
{
case FLV_VIDEO_FOURCC_AV1:
video->codecid = FLV_VIDEO_AV1;
return 5;
//case FLV_VIDEO_FOURCC_VP9:
// video->codecid = FLV_VIDEO_VP9;
// break;
case FLV_VIDEO_FOURCC_HEVC:
case FLV_VIDEO_FOURCC_VVC:
video->codecid = (FLV_VIDEO_FOURCC(buf[1], buf[2], buf[3], buf[4]) == FLV_VIDEO_FOURCC_HEVC) ? FLV_VIDEO_H265 : FLV_VIDEO_H266;
if(len >= 8 && FLV_AVPACKET == video->avpacket)
{
video->cts = ((uint32_t)buf[5] << 16) | ((uint32_t)buf[6] << 8) | buf[7];
//if (video->cts >= (1 << 23)) video->cts -= (1 << 24);
video->cts = (video->cts + 0xFF800000) ^ 0xFF800000; // signed 24-integer
return 8;
}
else
{
if (FLV_PACKET_TYPE_CODED_FRAMES_X == video->avpacket)
video->avpacket = FLV_AVPACKET;
video->cts = 0;
return 5;
}
break;
default:
video->codecid = 0; // unknown
}
return 5;
}
video->keyframe = (buf[0] & 0xF0) >> 4;
video->codecid = (buf[0] & 0x0F);
video->avpacket = FLV_AVPACKET;
if (FLV_VIDEO_H264 == video->codecid || FLV_VIDEO_H265 == video->codecid || FLV_VIDEO_H266 == video->codecid || FLV_VIDEO_AV1 == video->codecid || FLV_VIDEO_AVS3 == video->codecid)
{
if (len < 5)
return -1;
video->avpacket = buf[1]; // AVCPacketType
video->cts = ((uint32_t)buf[2] << 16) | ((uint32_t)buf[3] << 8) | buf[4];
//if (video->cts >= (1 << 23)) video->cts -= (1 << 24);
video->cts = (video->cts + 0xFF800000) ^ 0xFF800000; // signed 24-integer
assert(FLV_SEQUENCE_HEADER == video->avpacket || FLV_AVPACKET == video->avpacket || FLV_END_OF_SEQUENCE == video->avpacket);
return 5;
}
else
{
return 1;
}
}
int flv_data_tag_header_read(const uint8_t* buf, size_t len)
{
(void)buf;
return (int)len;
}
int flv_header_write(int audio, int video, uint8_t* buf, size_t len)
{
if (len < FLV_HEADER_SIZE)
{
assert(0);
return -1;
}
buf[0] = 'F'; // FLV signature
buf[1] = 'L';
buf[2] = 'V';
buf[3] = 0x01; // File version
buf[4] = ((audio ? 1 : 0) << 2) | (video ? 1 : 0); // Type flags (audio & video)
be_write_uint32(buf + 5, FLV_HEADER_SIZE); // Data offset
return FLV_HEADER_SIZE;
}
int flv_tag_header_write(const struct flv_tag_header_t* tag, uint8_t* buf, size_t len)
{
if (len < FLV_TAG_HEADER_SIZE)
{
assert(0);
return -1;
}
// TagType
assert(FLV_TYPE_VIDEO == tag->type || FLV_TYPE_AUDIO == tag->type || FLV_TYPE_SCRIPT == tag->type);
buf[0] = (tag->type & 0x1F) | ((tag->filter & 0x01) << 5);
// DataSize
buf[1] = (tag->size >> 16) & 0xFF;
buf[2] = (tag->size >> 8) & 0xFF;
buf[3] = tag->size & 0xFF;
// Timestamp
buf[4] = (tag->timestamp >> 16) & 0xFF;
buf[5] = (tag->timestamp >> 8) & 0xFF;
buf[6] = (tag->timestamp >> 0) & 0xFF;
buf[7] = (tag->timestamp >> 24) & 0xFF; // Timestamp Extended
// StreamID(Always 0)
buf[8] = (tag->streamId >> 16) & 0xFF;
buf[9] = (tag->streamId >> 8) & 0xFF;
buf[10] = (tag->streamId) & 0xFF;
return FLV_TAG_HEADER_SIZE;
}
int flv_audio_tag_header_write(const struct flv_audio_tag_header_t* audio, uint8_t* buf, size_t len)
{
if ((int)len < 1 + ((FLV_AUDIO_AAC == audio->codecid || FLV_AUDIO_OPUS == audio->codecid)? 1 : 0))
return -1;
if (FLV_AUDIO_AAC == audio->codecid || FLV_AUDIO_OPUS == audio->codecid)
{
assert(FLV_SEQUENCE_HEADER == audio->avpacket || FLV_AVPACKET == audio->avpacket);
buf[0] = (audio->codecid /* <<4 */) /* SoundFormat */ | (3 << 2) /* 44k-SoundRate */ | (1 << 1) /* 16-bit samples */ | 1 /* Stereo sound */;
buf[1] = audio->avpacket; // AACPacketType
return 2;
}
else
{
buf[0] = (audio->codecid /* <<4 */) | ((audio->rate & 0x03) << 2) | ((audio->bits & 0x01) << 1) | (audio->channels & 0x01);
return 1;
}
}
int flv_video_tag_header_write(const struct flv_video_tag_header_t* video, uint8_t* buf, size_t len)
{
#ifdef FLV_ENHANCE_RTMP
// https://github.com/veovera/enhanced-rtmp/blob/main/enhanced-rtmp.pdf
if (len < 5)
return -1;
buf[0] = 0x80 | (video->keyframe << 4) /*FrameType*/;
buf[0] |= (0 == video->cts && FLV_AVPACKET == video->avpacket) ? FLV_PACKET_TYPE_CODED_FRAMES_X : video->avpacket;
switch (video->codecid)
{
case FLV_VIDEO_AV1:
buf[1] = (FLV_VIDEO_FOURCC_AV1 >> 24) & 0xFF;
buf[2] = (FLV_VIDEO_FOURCC_AV1 >> 16) & 0xFF;
buf[3] = (FLV_VIDEO_FOURCC_AV1 >> 8) & 0xFF;
buf[4] = (FLV_VIDEO_FOURCC_AV1) & 0xFF;
return 5;
case FLV_VIDEO_H265:
buf[1] = (FLV_VIDEO_FOURCC_HEVC >> 24) & 0xFF;
buf[2] = (FLV_VIDEO_FOURCC_HEVC >> 16) & 0xFF;
buf[3] = (FLV_VIDEO_FOURCC_HEVC >> 8) & 0xFF;
buf[4] = (FLV_VIDEO_FOURCC_HEVC) & 0xFF;
if (len >= 8 && FLV_AVPACKET == video->avpacket && video->cts != 0)
{
buf[5] = (video->cts >> 16) & 0xFF;
buf[6] = (video->cts >> 8) & 0xFF;
buf[7] = video->cts & 0xFF;
return 8;
}
return 5;
case FLV_VIDEO_H266:
buf[1] = (FLV_VIDEO_FOURCC_VVC >> 24) & 0xFF;
buf[2] = (FLV_VIDEO_FOURCC_VVC >> 16) & 0xFF;
buf[3] = (FLV_VIDEO_FOURCC_VVC >> 8) & 0xFF;
buf[4] = (FLV_VIDEO_FOURCC_VVC) & 0xFF;
if (len >= 8 && FLV_AVPACKET == video->avpacket && video->cts != 0)
{
buf[5] = (video->cts >> 16) & 0xFF;
buf[6] = (video->cts >> 8) & 0xFF;
buf[7] = video->cts & 0xFF;
return 8;
}
return 5;
default:
break; // fallthrough
}
#endif
if (len < 1)
return -1;
buf[0] = (video->keyframe << 4) /*FrameType*/ | (video->codecid & 0x0F) /*CodecID*/;
if (FLV_VIDEO_H264 == video->codecid || FLV_VIDEO_H265 == video->codecid || FLV_VIDEO_H266 == video->codecid || FLV_VIDEO_AV1 == video->codecid)
{
assert(FLV_SEQUENCE_HEADER == video->avpacket || FLV_AVPACKET == video->avpacket || FLV_END_OF_SEQUENCE == video->avpacket);
if (len < 5)
return -1;
buf[1] = video->avpacket; // AVCPacketType
buf[2] = (video->cts >> 16) & 0xFF;
buf[3] = (video->cts >> 8) & 0xFF;
buf[4] = video->cts & 0xFF;
return 5;
}
return 1;
}
int flv_data_tag_header_write(uint8_t* buf, size_t len)
{
(void)buf;
(void)len;
return 0;
}
int flv_tag_size_read(const uint8_t* buf, size_t len, uint32_t* size)
{
if(len < 4)
return -1;
*size = be_read_uint32(buf);
return 4;
}
int flv_tag_size_write(uint8_t* buf, size_t len, uint32_t size)
{
if(len < 4)
return -1;
be_write_uint32(buf, size);
return 4;
}