[FFmpeg-devel] [PATCH 02/14] avformat/flvdec: add support for demuxing multi-track FLV
Timo Rothenpieler
timo at rothenpieler.org
Thu Dec 12 21:55:27 EET 2024
From: Dennis Sädtler <dennis at obsproject.com>
Based on enhanced-rtmp v2 spec published by Veovera:
https://veovera.github.io/enhanced-rtmp/docs/enhanced/enhanced-rtmp-v2
Signed-off-by: Dennis Sädtler <dennis at obsproject.com>
---
libavformat/flvdec.c | 117 +++++++++++++++++++++++++++++++++++--------
1 file changed, 96 insertions(+), 21 deletions(-)
diff --git a/libavformat/flvdec.c b/libavformat/flvdec.c
index 08482eb2db..19ef2103b6 100644
--- a/libavformat/flvdec.c
+++ b/libavformat/flvdec.c
@@ -104,6 +104,10 @@ typedef struct FLVContext {
FLVMetaVideoColor *metaVideoColor;
int meta_color_info_flag;
+
+ uint8_t **mt_extradata;
+ int *mt_extradata_sz;
+ int mt_extradata_cnt;
} FLVContext;
/* AMF date type */
@@ -186,7 +190,7 @@ static void add_keyframes_index(AVFormatContext *s)
}
}
-static AVStream *create_stream(AVFormatContext *s, int codec_type)
+static AVStream *create_stream(AVFormatContext *s, int codec_type, int track_idx)
{
FFFormatContext *const si = ffformatcontext(s);
FLVContext *flv = s->priv_data;
@@ -194,6 +198,11 @@ static AVStream *create_stream(AVFormatContext *s, int codec_type)
if (!st)
return NULL;
st->codecpar->codec_type = codec_type;
+ st->id = track_idx;
+ avpriv_set_pts_info(st, 32, 1, 1000); /* 32 bit pts in ms */
+ if (track_idx)
+ return st;
+
if (s->nb_streams>=3 ||( s->nb_streams==2
&& s->streams[0]->codecpar->codec_type != AVMEDIA_TYPE_SUBTITLE
&& s->streams[1]->codecpar->codec_type != AVMEDIA_TYPE_SUBTITLE
@@ -210,8 +219,6 @@ static AVStream *create_stream(AVFormatContext *s, int codec_type)
st->avg_frame_rate = flv->framerate;
}
-
- avpriv_set_pts_info(st, 32, 1, 1000); /* 32 bit pts in ms */
flv->last_keyframe_stream_index = s->nb_streams - 1;
add_keyframes_index(s);
return st;
@@ -351,6 +358,7 @@ static int flv_same_video_codec(AVCodecParameters *vpar, uint32_t flv_codecid)
case FLV_CODECID_VP6A:
return vpar->codec_id == AV_CODEC_ID_VP6A;
case FLV_CODECID_H264:
+ case MKBETAG('a', 'v', 'c', '1'):
return vpar->codec_id == AV_CODEC_ID_H264;
default:
return vpar->codec_tag == flv_codecid;
@@ -407,6 +415,7 @@ static int flv_set_video_codec(AVFormatContext *s, AVStream *vstream,
ret = 1; // 1 byte body size adjustment for flv_read_packet()
break;
case FLV_CODECID_H264:
+ case MKBETAG('a', 'v', 'c', '1'):
par->codec_id = AV_CODEC_ID_H264;
vstreami->need_parsing = AVSTREAM_PARSE_HEADERS;
break;
@@ -676,7 +685,7 @@ static int amf_parse_object(AVFormatContext *s, AVStream *astream,
} else if (!strcmp(key, "height") && vpar) {
vpar->height = num_val;
} else if (!strcmp(key, "datastream")) {
- AVStream *st = create_stream(s, AVMEDIA_TYPE_SUBTITLE);
+ AVStream *st = create_stream(s, AVMEDIA_TYPE_SUBTITLE, 0);
if (!st)
return AVERROR(ENOMEM);
st->codecpar->codec_id = AV_CODEC_ID_TEXT;
@@ -886,6 +895,9 @@ static int flv_read_close(AVFormatContext *s)
FLVContext *flv = s->priv_data;
for (i=0; i<FLV_STREAM_TYPE_NB; i++)
av_freep(&flv->new_extradata[i]);
+ for (i=0; i < flv->mt_extradata_cnt; i++)
+ av_freep(&flv->mt_extradata[i]);
+ av_freep(&flv->mt_extradata_sz);
av_freep(&flv->keyframe_times);
av_freep(&flv->keyframe_filepositions);
av_freep(&flv->metaVideoColor);
@@ -905,18 +917,47 @@ static int flv_get_extradata(AVFormatContext *s, AVStream *st, int size)
}
static int flv_queue_extradata(FLVContext *flv, AVIOContext *pb, int stream,
- int size)
+ int size, int multitrack)
{
if (!size)
return 0;
- av_free(flv->new_extradata[stream]);
- flv->new_extradata[stream] = av_mallocz(size +
- AV_INPUT_BUFFER_PADDING_SIZE);
- if (!flv->new_extradata[stream])
- return AVERROR(ENOMEM);
- flv->new_extradata_size[stream] = size;
- avio_read(pb, flv->new_extradata[stream], size);
+ if (!multitrack) {
+ av_free(flv->new_extradata[stream]);
+ flv->new_extradata[stream] = av_mallocz(size +
+ AV_INPUT_BUFFER_PADDING_SIZE);
+ if (!flv->new_extradata[stream])
+ return AVERROR(ENOMEM);
+ flv->new_extradata_size[stream] = size;
+ avio_read(pb, flv->new_extradata[stream], size);
+ } else {
+ int new_count = stream + 1;
+
+ if (flv->mt_extradata_cnt < new_count) {
+ flv->mt_extradata = av_realloc(flv->mt_extradata,
+ sizeof(*flv->mt_extradata) *
+ new_count);
+ flv->mt_extradata_sz = av_realloc(flv->mt_extradata_sz,
+ sizeof(*flv->mt_extradata_sz) *
+ new_count);
+ if (!flv->mt_extradata || !flv->mt_extradata_sz)
+ return AVERROR(ENOMEM);
+ // Set newly allocated pointers/sizes to 0
+ for (int i = flv->mt_extradata_cnt; i < new_count; i++) {
+ flv->mt_extradata[i] = NULL;
+ flv->mt_extradata_sz[i] = 0;
+ }
+ flv->mt_extradata_cnt = new_count;
+ }
+
+ av_free(flv->mt_extradata[stream]);
+ flv->mt_extradata[stream] = av_mallocz(size + AV_INPUT_BUFFER_PADDING_SIZE);
+ if (!flv->mt_extradata[stream])
+ return AVERROR(ENOMEM);
+ flv->mt_extradata_sz[stream] = size;
+ avio_read(pb, flv->mt_extradata[stream], size);
+ }
+
return 0;
}
@@ -1032,7 +1073,7 @@ static int flv_data_packet(AVFormatContext *s, AVPacket *pkt,
}
if (i == s->nb_streams) {
- st = create_stream(s, AVMEDIA_TYPE_SUBTITLE);
+ st = create_stream(s, AVMEDIA_TYPE_SUBTITLE, 0);
if (!st)
return AVERROR(ENOMEM);
st->codecpar->codec_id = AV_CODEC_ID_TEXT;
@@ -1205,6 +1246,9 @@ static int flv_read_packet(AVFormatContext *s, AVPacket *pkt)
int last = -1;
int orig_size;
int enhanced_flv = 0;
+ int multitrack = 0;
+ int pkt_type = 0;
+ uint8_t track_idx = 0;
uint32_t video_codec_id = 0;
retry:
@@ -1258,14 +1302,33 @@ retry:
* https://github.com/veovera/enhanced-rtmp/blob/main/enhanced-rtmp-v1.pdf
* */
enhanced_flv = (flags >> 7) & 1;
+ pkt_type = enhanced_flv ? video_codec_id : 0;
size--;
+
+ if (pkt_type == PacketTypeMultitrack) {
+ uint8_t types = avio_r8(s->pb);
+ int multitrack_type = types >> 4;
+ pkt_type = types & 0xF;
+
+ if (multitrack_type != MultitrackTypeOneTrack) {
+ av_log(s, AV_LOG_ERROR, "Multitrack types other than MultitrackTypeOneTrack are unsupported!\n");
+ return AVERROR_PATCHWELCOME;
+ }
+
+ multitrack = 1;
+ size--;
+ }
+
if (enhanced_flv) {
video_codec_id = avio_rb32(s->pb);
size -= 4;
}
+ if (multitrack) {
+ track_idx = avio_r8(s->pb);
+ size--;
+ }
- if (enhanced_flv && stream_type == FLV_STREAM_TYPE_VIDEO && (flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_VIDEO_INFO_CMD) {
- int pkt_type = flags & 0x0F;
+ if (enhanced_flv && (flags & FLV_VIDEO_FRAMETYPE_MASK) == FLV_FRAME_VIDEO_INFO_CMD) {
if (pkt_type == PacketTypeMetadata) {
int ret = flv_parse_video_color_info(s, st, next);
av_log(s, AV_LOG_DEBUG, "enhanced flv parse metadata ret %d and skip\n", ret);
@@ -1329,7 +1392,8 @@ skip:
break;
} else if (stream_type == FLV_STREAM_TYPE_VIDEO) {
if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO &&
- (s->video_codec_id || flv_same_video_codec(st->codecpar, video_codec_id)))
+ (s->video_codec_id || flv_same_video_codec(st->codecpar, video_codec_id)) &&
+ st->id == track_idx)
break;
} else if (stream_type == FLV_STREAM_TYPE_SUBTITLE) {
if (st->codecpar->codec_type == AVMEDIA_TYPE_SUBTITLE)
@@ -1341,7 +1405,7 @@ skip:
}
if (i == s->nb_streams) {
static const enum AVMediaType stream_types[] = {AVMEDIA_TYPE_VIDEO, AVMEDIA_TYPE_AUDIO, AVMEDIA_TYPE_SUBTITLE, AVMEDIA_TYPE_DATA};
- st = create_stream(s, stream_types[stream_type]);
+ st = create_stream(s, stream_types[stream_type], track_idx);
if (!st)
return AVERROR(ENOMEM);
}
@@ -1448,7 +1512,7 @@ retry_duration:
st->codecpar->codec_id == AV_CODEC_ID_VP9) {
int type = 0;
if (enhanced_flv && stream_type == FLV_STREAM_TYPE_VIDEO) {
- type = flags & 0x0F;
+ type = pkt_type;
} else {
type = avio_r8(s->pb);
size--;
@@ -1464,7 +1528,8 @@ retry_duration:
flv->meta_color_info_flag = 0;
}
- if (st->codecpar->codec_id == AV_CODEC_ID_H264 || st->codecpar->codec_id == AV_CODEC_ID_MPEG4 ||
+ if (st->codecpar->codec_id == AV_CODEC_ID_MPEG4 ||
+ (st->codecpar->codec_id == AV_CODEC_ID_H264 && (!enhanced_flv || type == PacketTypeCodedFrames)) ||
(st->codecpar->codec_id == AV_CODEC_ID_HEVC && type == PacketTypeCodedFrames)) {
// sign extension
int32_t cts = (avio_rb24(s->pb) + 0xff800000) ^ 0xff800000;
@@ -1487,7 +1552,7 @@ retry_duration:
AVDictionaryEntry *t;
if (st->codecpar->extradata) {
- if ((ret = flv_queue_extradata(flv, s->pb, stream_type, size)) < 0)
+ if ((ret = flv_queue_extradata(flv, s->pb, multitrack ? track_idx : stream_type, size, multitrack)) < 0)
return ret;
ret = FFERROR_REDO;
goto leave;
@@ -1518,7 +1583,7 @@ retry_duration:
pkt->pts = pts == AV_NOPTS_VALUE ? dts : pts;
pkt->stream_index = st->index;
pkt->pos = pos;
- if (flv->new_extradata[stream_type]) {
+ if (!multitrack && flv->new_extradata[stream_type]) {
int ret = av_packet_add_side_data(pkt, AV_PKT_DATA_NEW_EXTRADATA,
flv->new_extradata[stream_type],
flv->new_extradata_size[stream_type]);
@@ -1526,6 +1591,16 @@ retry_duration:
flv->new_extradata[stream_type] = NULL;
flv->new_extradata_size[stream_type] = 0;
}
+ } else if (multitrack
+ && flv->mt_extradata_cnt > track_idx
+ && flv->mt_extradata[track_idx]) {
+ int ret = av_packet_add_side_data(pkt, AV_PKT_DATA_NEW_EXTRADATA,
+ flv->mt_extradata[track_idx],
+ flv->mt_extradata_sz[track_idx]);
+ if (ret >= 0) {
+ flv->mt_extradata[track_idx] = NULL;
+ flv->mt_extradata_sz[track_idx] = 0;
+ }
}
if (stream_type == FLV_STREAM_TYPE_AUDIO &&
(sample_rate != flv->last_sample_rate ||
--
2.45.2
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