[FFmpeg-devel] [PATCH v5 1/3] avformat/hlsenc:addition of #EXT-X-MEDIA tag and AUDIO attribute
vdixit at akamai.com
vdixit at akamai.com
Thu Nov 30 13:32:23 EET 2017
From: Vishwanath Dixit <vdixit at akamai.com>
---
doc/muxers.texi | 12 +++++++++
libavformat/dashenc.c | 3 ++-
libavformat/hlsenc.c | 62 ++++++++++++++++++++++++++++++++++++++++++++---
libavformat/hlsplaylist.c | 4 ++-
libavformat/hlsplaylist.h | 2 +-
5 files changed, 77 insertions(+), 6 deletions(-)
diff --git a/doc/muxers.texi b/doc/muxers.texi
index 3d0c7bf..93db549 100644
--- a/doc/muxers.texi
+++ b/doc/muxers.texi
@@ -834,6 +834,18 @@ be a video only stream with video bitrate 1000k, the second variant stream will
be an audio only stream with bitrate 64k and the third variant stream will be a
video only stream with bitrate 256k. Here, three media playlist with file names
out_1.m3u8, out_2.m3u8 and out_3.m3u8 will be created.
+ at example
+ffmpeg -re -i in.ts -b:a:0 32k -b:a:1 64k -b:v:0 1000k -b:v:1 3000k \
+ -map 0:a -map 0:a -map 0:v -map 0:v -f hls \
+ -var_stream_map "a:0,agroup:aud_low a:1,agroup:aud_high v:0,agroup:aud_low v:1,agroup:aud_high" \
+ -master_pl_name master.m3u8 \
+ http://example.com/live/out.m3u8
+ at end example
+This example creates two audio only and two video only variant streams. In
+addition to the #EXT-X-STREAM-INF tag for each variant stream in the master
+playlist, #EXT-X-MEDIA tag is also added for the two audio only variant streams
+and they are mapped to the two video only variant streams with audio group names
+'aud_low' and 'aud_high'.
By default, a single hls variant containing all the encoded streams is created.
diff --git a/libavformat/dashenc.c b/libavformat/dashenc.c
index 1783675..90cd2d0 100644
--- a/libavformat/dashenc.c
+++ b/libavformat/dashenc.c
@@ -753,7 +753,8 @@ static int write_manifest(AVFormatContext *s, int final)
char playlist_file[64];
AVStream *st = s->streams[i];
get_hls_playlist_name(playlist_file, sizeof(playlist_file), NULL, i);
- ff_hls_write_stream_info(st, out, st->codecpar->bit_rate, playlist_file);
+ ff_hls_write_stream_info(st, out, st->codecpar->bit_rate,
+ playlist_file, NULL);
}
avio_close(out);
if (use_rename)
diff --git a/libavformat/hlsenc.c b/libavformat/hlsenc.c
index cdfbf45..8d4b333 100644
--- a/libavformat/hlsenc.c
+++ b/libavformat/hlsenc.c
@@ -142,6 +142,7 @@ typedef struct VariantStream {
AVStream **streams;
unsigned int nb_streams;
int m3u8_created; /* status of media play-list creation */
+ char *agroup; /* audio group name */
char *baseurl;
} VariantStream;
@@ -1077,7 +1078,7 @@ static int create_master_playlist(AVFormatContext *s,
VariantStream * const input_vs)
{
HLSContext *hls = s->priv_data;
- VariantStream *vs;
+ VariantStream *vs, *temp_vs;
AVStream *vid_st, *aud_st;
AVIOContext *master_pb = 0;
AVDictionary *options = NULL;
@@ -1111,6 +1112,34 @@ static int create_master_playlist(AVFormatContext *s,
ff_hls_write_playlist_version(master_pb, hls->version);
+ /* For audio only variant streams add #EXT-X-MEDIA tag with attributes*/
+ for (i = 0; i < hls->nb_varstreams; i++) {
+ vs = &(hls->var_streams[i]);
+
+ if (vs->has_video || vs->has_subtitle || !vs->agroup)
+ continue;
+
+ m3u8_name_size = strlen(vs->m3u8_name) + 1;
+ m3u8_rel_name = av_malloc(m3u8_name_size);
+ if (!m3u8_rel_name) {
+ ret = AVERROR(ENOMEM);
+ goto fail;
+ }
+ av_strlcpy(m3u8_rel_name, vs->m3u8_name, m3u8_name_size);
+ ret = get_relative_url(hls->master_m3u8_url, vs->m3u8_name,
+ m3u8_rel_name, m3u8_name_size);
+ if (ret < 0) {
+ av_log(s, AV_LOG_ERROR, "Unable to find relative URL\n");
+ goto fail;
+ }
+
+ avio_printf(master_pb, "#EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID=\"group_%s\"",
+ vs->agroup);
+ avio_printf(master_pb, ",NAME=\"audio_0\",DEFAULT=YES,URI=\"%s\"\n",
+ m3u8_rel_name);
+ av_freep(&m3u8_rel_name);
+ }
+
/* For variant streams with video add #EXT-X-STREAM-INF tag with attributes*/
for (i = 0; i < hls->nb_varstreams; i++) {
vs = &(hls->var_streams[i]);
@@ -1143,6 +1172,25 @@ static int create_master_playlist(AVFormatContext *s,
continue;
}
+ /**
+ * Traverse through the list of audio only rendition streams and find
+ * the rendition which has highest bitrate in the same audio group
+ */
+ if (vs->agroup) {
+ for (j = 0; j < hls->nb_varstreams; j++) {
+ temp_vs = &(hls->var_streams[j]);
+ if (!temp_vs->has_video && !temp_vs->has_subtitle &&
+ temp_vs->agroup &&
+ !strcmp(temp_vs->agroup, vs->agroup)) {
+ if (!aud_st)
+ aud_st = temp_vs->streams[0];
+ if (temp_vs->streams[0]->codecpar->bit_rate >
+ aud_st->codecpar->bit_rate)
+ aud_st = temp_vs->streams[0];
+ }
+ }
+ }
+
bandwidth = 0;
if (vid_st)
bandwidth += vid_st->codecpar->bit_rate;
@@ -1150,7 +1198,8 @@ static int create_master_playlist(AVFormatContext *s,
bandwidth += aud_st->codecpar->bit_rate;
bandwidth += bandwidth / 10;
- ff_hls_write_stream_info(vid_st, master_pb, bandwidth, m3u8_rel_name);
+ ff_hls_write_stream_info(vid_st, master_pb, bandwidth, m3u8_rel_name,
+ aud_st ? vs->agroup : NULL);
av_freep(&m3u8_rel_name);
}
@@ -1500,6 +1549,7 @@ static int parse_variant_stream_mapstring(AVFormatContext *s)
/**
* Expected format for var_stream_map string is as below:
* "a:0,v:0 a:1,v:1"
+ * "a:0,agroup:a0 a:1,agroup:a1 v:0,agroup:a0 v:1,agroup:a1"
* This string specifies how to group the audio, video and subtitle streams
* into different variant streams. The variant stream groups are separated
* by space.
@@ -1508,6 +1558,7 @@ static int parse_variant_stream_mapstring(AVFormatContext *s)
* respectively. Allowed values are 0 to 9 digits (limited just based on
* practical usage)
*
+ * agroup: is key to specify audio group. A string can be given as value.
*/
p = av_strdup(hls->var_stream_map);
q = p;
@@ -1546,7 +1597,10 @@ static int parse_variant_stream_mapstring(AVFormatContext *s)
while (keyval = av_strtok(varstr, ",", &saveptr2)) {
varstr = NULL;
- if (av_strstart(keyval, "v:", &val)) {
+ if (av_strstart(keyval, "agroup:", &val)) {
+ vs->agroup = av_strdup(val);
+ continue;
+ } else if (av_strstart(keyval, "v:", &val)) {
codec_type = AVMEDIA_TYPE_VIDEO;
} else if (av_strstart(keyval, "a:", &val)) {
codec_type = AVMEDIA_TYPE_AUDIO;
@@ -2005,6 +2059,7 @@ fail:
av_freep(&vs->m3u8_name);
av_freep(&vs->vtt_m3u8_name);
av_freep(&vs->streams);
+ av_freep(&vs->agroup);
av_freep(&vs->baseurl);
if (vs->avf)
avformat_free_context(vs->avf);
@@ -2246,6 +2301,7 @@ static int hls_write_trailer(struct AVFormatContext *s)
av_free(old_filename);
av_freep(&vs->m3u8_name);
av_freep(&vs->streams);
+ av_freep(&vs->agroup);
av_freep(&vs->baseurl);
}
diff --git a/libavformat/hlsplaylist.c b/libavformat/hlsplaylist.c
index 235e519..5e12682 100644
--- a/libavformat/hlsplaylist.c
+++ b/libavformat/hlsplaylist.c
@@ -36,7 +36,7 @@ void ff_hls_write_playlist_version(AVIOContext *out, int version) {
}
void ff_hls_write_stream_info(AVStream *st, AVIOContext *out,
- int bandwidth, char *filename) {
+ int bandwidth, char *filename, char *agroup) {
if (!out || !filename)
return;
@@ -50,6 +50,8 @@ void ff_hls_write_stream_info(AVStream *st, AVIOContext *out,
if (st && st->codecpar->width > 0 && st->codecpar->height > 0)
avio_printf(out, ",RESOLUTION=%dx%d", st->codecpar->width,
st->codecpar->height);
+ if (agroup && strlen(agroup) > 0)
+ avio_printf(out, ",AUDIO=\"group_%s\"", agroup);
avio_printf(out, "\n%s\n\n", filename);
}
diff --git a/libavformat/hlsplaylist.h b/libavformat/hlsplaylist.h
index 4cbc8ca..3231733 100644
--- a/libavformat/hlsplaylist.h
+++ b/libavformat/hlsplaylist.h
@@ -43,7 +43,7 @@ static inline int hls_get_int_from_double(double val)
void ff_hls_write_playlist_version(AVIOContext *out, int version);
void ff_hls_write_stream_info(AVStream *st, AVIOContext *out,
- int bandwidth, char *filename);
+ int bandwidth, char *filename, char *agroup);
void ff_hls_write_playlist_header(AVIOContext *out, int version, int allowcache,
int target_duration, int64_t sequence,
uint32_t playlist_type);
--
1.9.1
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