[FFmpeg-devel] [PATCH 09/13] avformat/flvenc: add support for writing multi track audio
Timo Rothenpieler
timo at rothenpieler.org
Tue May 21 12:02:18 EEST 2024
---
libavformat/flvenc.c | 90 +++++++++++++++++++++++++++++++++-----------
1 file changed, 67 insertions(+), 23 deletions(-)
diff --git a/libavformat/flvenc.c b/libavformat/flvenc.c
index 056940afc5..ab729702a5 100644
--- a/libavformat/flvenc.c
+++ b/libavformat/flvenc.c
@@ -131,7 +131,7 @@ typedef struct FLVContext {
int flags;
int64_t *last_ts;
int *metadata_pkt_written;
- int *video_track_idx_map;
+ int *track_idx_map;
} FLVContext;
static int get_audio_flags(AVFormatContext *s, AVCodecParameters *par)
@@ -764,19 +764,33 @@ static int flv_get_multichannel_body_size(AVCodecParameters* par)
return res;
}
-static void flv_write_multichannel_header(AVFormatContext* s, AVCodecParameters* par, int64_t ts)
+static void flv_write_multichannel_header(AVFormatContext* s, AVCodecParameters* par, int64_t ts, int stream_index)
{
AVIOContext *pb = s->pb;
+ FLVContext *flv = s->priv_data;
+
+ int track_idx = flv->track_idx_map[stream_index];
int data_size = flv_get_multichannel_body_size(par);
+ if (track_idx)
+ data_size += 2;
avio_w8(pb, FLV_TAG_TYPE_AUDIO);
avio_wb24(pb, data_size + 5); // size
put_timestamp(pb, ts);
avio_wb24(pb, 0); // streamid
- avio_w8(pb, FLV_CODECID_EX_HEADER | AudioPacketTypeMultichannelConfig);
+ if (track_idx) {
+ avio_w8(pb, FLV_CODECID_EX_HEADER | AudioPacketTypeMultitrack);
+ avio_w8(pb, MultitrackTypeOneTrack | AudioPacketTypeMultichannelConfig);
+ } else {
+ avio_w8(pb, FLV_CODECID_EX_HEADER | AudioPacketTypeMultichannelConfig);
+ }
+
write_codec_fourcc(pb, par->codec_id);
+ if (track_idx)
+ avio_w8(pb, track_idx);
+
flv_write_multichannel_body(s, par);
avio_wb32(pb, data_size + 5 + 11); // previous tag size
@@ -786,6 +800,7 @@ static void flv_write_codec_header(AVFormatContext* s, AVCodecParameters* par, i
int64_t data_size;
AVIOContext *pb = s->pb;
FLVContext *flv = s->priv_data;
+ int track_idx = flv->track_idx_map[stream_index];
int extended_flv = 0;
if (par->codec_id == AV_CODEC_ID_AAC || par->codec_id == AV_CODEC_ID_H264
@@ -802,15 +817,26 @@ static void flv_write_codec_header(AVFormatContext* s, AVCodecParameters* par, i
avio_wb24(pb, 0); // streamid
pos = avio_tell(pb);
if (par->codec_type == AVMEDIA_TYPE_AUDIO) {
- extended_flv = par->codec_id == AV_CODEC_ID_OPUS
- || par->codec_id == AV_CODEC_ID_FLAC
- || par->codec_id == AV_CODEC_ID_AC3
- || par->codec_id == AV_CODEC_ID_EAC3;
+ extended_flv = (par->codec_id == AV_CODEC_ID_AAC && track_idx)
+ || (par->codec_id == AV_CODEC_ID_MP3 && track_idx)
+ || par->codec_id == AV_CODEC_ID_OPUS
+ || par->codec_id == AV_CODEC_ID_FLAC
+ || par->codec_id == AV_CODEC_ID_AC3
+ || par->codec_id == AV_CODEC_ID_EAC3;
if (extended_flv) {
- avio_w8(pb, FLV_CODECID_EX_HEADER | AudioPacketTypeSequenceStart);
+ if (track_idx) {
+ avio_w8(pb, FLV_CODECID_EX_HEADER | AudioPacketTypeMultitrack);
+ avio_w8(pb, MultitrackTypeOneTrack | AudioPacketTypeSequenceStart);
+ } else {
+ avio_w8(pb, FLV_CODECID_EX_HEADER | AudioPacketTypeSequenceStart);
+ }
+
write_codec_fourcc(pb, par->codec_id);
+ if (track_idx)
+ avio_w8(pb, track_idx);
+
if (par->codec_id == AV_CODEC_ID_AAC) {
flv_write_aac_header(s, par);
} else if (par->codec_id == AV_CODEC_ID_OPUS || par->codec_id == AV_CODEC_ID_FLAC) {
@@ -824,7 +850,6 @@ static void flv_write_codec_header(AVFormatContext* s, AVCodecParameters* par, i
flv_write_aac_header(s, par);
}
} else {
- int track_idx = flv->video_track_idx_map[stream_index];
// If video stream has track_idx > 0 we need to send H.264 as extended video packet
extended_flv = (par->codec_id == AV_CODEC_ID_H264 && track_idx)
|| par->codec_id == AV_CODEC_ID_HEVC
@@ -868,7 +893,7 @@ static void flv_write_codec_header(AVFormatContext* s, AVCodecParameters* par, i
if (par->codec_type == AVMEDIA_TYPE_AUDIO && (extended_flv ||
(av_channel_layout_compare(&par->ch_layout, &(AVChannelLayout)AV_CHANNEL_LAYOUT_STEREO) == 1 &&
av_channel_layout_compare(&par->ch_layout, &(AVChannelLayout)AV_CHANNEL_LAYOUT_MONO) == 1)))
- flv_write_multichannel_header(s, par, ts);
+ flv_write_multichannel_header(s, par, ts, stream_index);
}
static int flv_append_keyframe_info(AVFormatContext *s, FLVContext *flv, double ts, int64_t pos)
@@ -930,12 +955,12 @@ static int shift_data(AVFormatContext *s)
static int flv_init(struct AVFormatContext *s)
{
int i;
- int video_ctr = 0;
+ int video_ctr = 0, audio_ctr = 0;
FLVContext *flv = s->priv_data;
flv->last_ts = av_mallocz(sizeof(*flv->last_ts) * s->nb_streams);
flv->metadata_pkt_written = av_mallocz(sizeof(*flv->metadata_pkt_written) * s->nb_streams);
- flv->video_track_idx_map = av_mallocz(sizeof(*flv->video_track_idx_map) * s->nb_streams);
+ flv->track_idx_map = av_mallocz(sizeof(*flv->track_idx_map) * s->nb_streams);
for (i = 0; i < s->nb_streams; i++) {
AVCodecParameters *par = s->streams[i]->codecpar;
@@ -946,7 +971,7 @@ static int flv_init(struct AVFormatContext *s)
s->streams[i]->avg_frame_rate.num) {
flv->framerate = av_q2d(s->streams[i]->avg_frame_rate);
}
- flv->video_track_idx_map[i] = video_ctr++;
+ flv->track_idx_map[i] = video_ctr++;
if (flv->video_par && flv->flags & FLV_ADD_KEYFRAME_INDEX) {
av_log(s, AV_LOG_ERROR,
"at most one video stream is supported in flv with keyframe index\n");
@@ -977,12 +1002,22 @@ static int flv_init(struct AVFormatContext *s)
}
break;
case AVMEDIA_TYPE_AUDIO:
- if (flv->audio_par) {
- av_log(s, AV_LOG_ERROR,
- "at most one audio stream is supported in flv\n");
+ if (audio_ctr &&
+ par->codec_id != AV_CODEC_ID_AAC &&
+ par->codec_id != AV_CODEC_ID_MP3 &&
+ par->codec_id != AV_CODEC_ID_OPUS &&
+ par->codec_id != AV_CODEC_ID_FLAC &&
+ par->codec_id != AV_CODEC_ID_AC3 &&
+ par->codec_id != AV_CODEC_ID_EAC3) {
+ av_log(s, AV_LOG_ERROR, "Unsupported multi-track codec.\n");
return AVERROR(EINVAL);
}
- flv->audio_par = par;
+ flv->track_idx_map[i] = audio_ctr++;
+ if (flv->audio_par)
+ av_log(s, AV_LOG_WARNING,
+ "more than one audio stream is not supported by most flv demuxers.\n");
+ else
+ flv->audio_par = par;
if (get_audio_flags(s, par) < 0)
return unsupported_codec(s, "Audio", par->codec_id);
if (par->codec_id == AV_CODEC_ID_PCM_S16BE)
@@ -1154,9 +1189,11 @@ static int flv_write_packet(AVFormatContext *s, AVPacket *pkt)
uint8_t frametype = pkt->flags & AV_PKT_FLAG_KEY ? FLV_FRAME_KEY : FLV_FRAME_INTER;
int flags = -1, flags_size, ret = 0;
int64_t cur_offset = avio_tell(pb);
- int track_idx = flv->video_track_idx_map[pkt->stream_index];
+ int track_idx = flv->track_idx_map[pkt->stream_index];
- int extended_audio = par->codec_id == AV_CODEC_ID_OPUS
+ int extended_audio = (par->codec_id == AV_CODEC_ID_AAC && track_idx)
+ || (par->codec_id == AV_CODEC_ID_MP3 && track_idx)
+ || par->codec_id == AV_CODEC_ID_OPUS
|| par->codec_id == AV_CODEC_ID_FLAC
|| par->codec_id == AV_CODEC_ID_AC3
|| par->codec_id == AV_CODEC_ID_EAC3;
@@ -1173,8 +1210,8 @@ static int flv_write_packet(AVFormatContext *s, AVPacket *pkt)
else
flags_size = 1;
- if (par->codec_type == AVMEDIA_TYPE_VIDEO && track_idx)
- flags_size += 2; // additional header bytes for multi-track video
+ if ((par->codec_type == AVMEDIA_TYPE_VIDEO || par->codec_type == AVMEDIA_TYPE_AUDIO) && track_idx)
+ flags_size += 2; // additional header bytes for multi-track flv
if ((par->codec_id == AV_CODEC_ID_HEVC ||
(par->codec_id == AV_CODEC_ID_H264 && track_idx))
@@ -1341,8 +1378,15 @@ static int flv_write_packet(AVFormatContext *s, AVPacket *pkt)
if (h2645 && pkttype == PacketTypeCodedFrames)
avio_wb24(pb, pkt->pts - pkt->dts);
} else if (extended_audio) {
- avio_w8(pb, FLV_CODECID_EX_HEADER | AudioPacketTypeCodedFrames);
+ if (track_idx) {
+ avio_w8(pb, FLV_CODECID_EX_HEADER | AudioPacketTypeMultitrack);
+ avio_w8(pb, MultitrackTypeOneTrack | AudioPacketTypeCodedFrames);
+ } else {
+ avio_w8(pb, FLV_CODECID_EX_HEADER | AudioPacketTypeCodedFrames);
+ }
write_codec_fourcc(pb, par->codec_id);
+ if (track_idx)
+ avio_w8(pb, track_idx);
} else {
av_assert1(flags>=0);
avio_w8(pb, flags);
@@ -1432,7 +1476,7 @@ static void flv_deinit(AVFormatContext *s)
av_freep(&flv->last_ts);
av_freep(&flv->metadata_pkt_written);
- av_freep(&flv->video_track_idx_map);
+ av_freep(&flv->track_idx_map);
}
static const AVOption options[] = {
--
2.43.2
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