Re: [FFmpeg-devel] [PATCH v8 1/3] avformat/hlsenc:addition of #EXT-X-MEDIA tag and AUDIO attribute

[Steven Liu]

2017-12-22 19:30 GMT+08:00 刘歧 :
>
>
>> On 22 Dec 2017, at 19:05, Dixit, Vishwanath  wrote:
>>
>> On 12/19/17 11:53 AM, 刘歧 wrote:
>>> On 19 Dec 2017, at 14:09, vdi...@akamai.com wrote:
 From: Vishwanath Dixit 

 ---
 doc/muxers.texi   | 12 +
 libavformat/dashenc.c |  3 ++-
 libavformat/hlsenc.c  | 64 
 ---
 libavformat/hlsplaylist.c |  4 ++-
 libavformat/hlsplaylist.h |  2 +-
 5 files changed, 79 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.
 +@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
 +@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 5687530..f363418 100644
 --- a/libavformat/dashenc.c
 +++ b/libavformat/dashenc.c
 @@ -759,7 +759,8 @@ 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 e3442c3..53dc835 100644
 --- a/libavformat/hlsenc.c
 +++ b/libavformat/hlsenc.c
 @@ -144,6 +144,7 @@ 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;

 @@ -1085,7 +1086,7 @@ 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;
AVDictionary *options = NULL;
unsigned int i, j;
 @@ -1117,6 +1118,34 @@ static int create_master_playlist(AVFormatContext 
 *s,

ff_hls_write_playlist_version(hls->m3u8_out, 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(hls->m3u8_out, 
 "#EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID=\"group_%s\"",
 +vs->agroup);
 +avio_printf(hls->m3u8_out, 
 ",NAME=\"audio_0\",DEFAULT=YES,URI=\"%s\"\n",
 +m3u8_rel_name);
 +av_freep(_rel_name);
 +}
 +
/* For variant streams with video add #EXT-X-STREAM-INF tag with 
 attributes*/
for (i = 0; i < hls->nb_varstreams; i++) 

Re: [FFmpeg-devel] [PATCH v8 1/3] avformat/hlsenc:addition of #EXT-X-MEDIA tag and AUDIO attribute

[刘歧]

> On 22 Dec 2017, at 19:05, Dixit, Vishwanath  wrote:
> 
> On 12/19/17 11:53 AM, 刘歧 wrote:
>> On 19 Dec 2017, at 14:09, vdi...@akamai.com wrote:
>>> From: Vishwanath Dixit 
>>> 
>>> ---
>>> doc/muxers.texi   | 12 +
>>> libavformat/dashenc.c |  3 ++-
>>> libavformat/hlsenc.c  | 64 
>>> ---
>>> libavformat/hlsplaylist.c |  4 ++-
>>> libavformat/hlsplaylist.h |  2 +-
>>> 5 files changed, 79 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.
>>> +@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
>>> +@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 5687530..f363418 100644
>>> --- a/libavformat/dashenc.c
>>> +++ b/libavformat/dashenc.c
>>> @@ -759,7 +759,8 @@ 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 e3442c3..53dc835 100644
>>> --- a/libavformat/hlsenc.c
>>> +++ b/libavformat/hlsenc.c
>>> @@ -144,6 +144,7 @@ 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;
>>> 
>>> @@ -1085,7 +1086,7 @@ 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;
>>>AVDictionary *options = NULL;
>>>unsigned int i, j;
>>> @@ -1117,6 +1118,34 @@ static int create_master_playlist(AVFormatContext *s,
>>> 
>>>ff_hls_write_playlist_version(hls->m3u8_out, 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(hls->m3u8_out, 
>>> "#EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID=\"group_%s\"",
>>> +vs->agroup);
>>> +avio_printf(hls->m3u8_out, 
>>> ",NAME=\"audio_0\",DEFAULT=YES,URI=\"%s\"\n",
>>> +m3u8_rel_name);
>>> +av_freep(_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]);
>>> @@ -1149,6 +1178,25 @@ static int create_master_playlist(AVFormatContext *s,
>>>continue;
>>>}
>>> 
>>> +/**
>>> 

Re: [FFmpeg-devel] [PATCH v8 1/3] avformat/hlsenc:addition of #EXT-X-MEDIA tag and AUDIO attribute

[Dixit, Vishwanath]

On 12/19/17 11:53 AM, 刘歧 wrote:
> On 19 Dec 2017, at 14:09, vdi...@akamai.com wrote:
>> From: Vishwanath Dixit 
>>
>> ---
>> doc/muxers.texi   | 12 +
>> libavformat/dashenc.c |  3 ++-
>> libavformat/hlsenc.c  | 64 
>> ---
>> libavformat/hlsplaylist.c |  4 ++-
>> libavformat/hlsplaylist.h |  2 +-
>> 5 files changed, 79 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.
>> +@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
>> +@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 5687530..f363418 100644
>> --- a/libavformat/dashenc.c
>> +++ b/libavformat/dashenc.c
>> @@ -759,7 +759,8 @@ 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 e3442c3..53dc835 100644
>> --- a/libavformat/hlsenc.c
>> +++ b/libavformat/hlsenc.c
>> @@ -144,6 +144,7 @@ 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;
>>
>> @@ -1085,7 +1086,7 @@ 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;
>> AVDictionary *options = NULL;
>> unsigned int i, j;
>> @@ -1117,6 +1118,34 @@ static int create_master_playlist(AVFormatContext *s,
>>
>> ff_hls_write_playlist_version(hls->m3u8_out, 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(hls->m3u8_out, 
>> "#EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID=\"group_%s\"",
>> +vs->agroup);
>> +avio_printf(hls->m3u8_out, 
>> ",NAME=\"audio_0\",DEFAULT=YES,URI=\"%s\"\n",
>> +m3u8_rel_name);
>> +av_freep(_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]);
>> @@ -1149,6 +1178,25 @@ 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 

Re: [FFmpeg-devel] [PATCH v8 1/3] avformat/hlsenc:addition of #EXT-X-MEDIA tag and AUDIO attribute

[刘歧]

On 19 Dec 2017, at 14:09, vdi...@akamai.com wrote:
> 
> From: Vishwanath Dixit 
> 
> ---
> doc/muxers.texi   | 12 +
> libavformat/dashenc.c |  3 ++-
> libavformat/hlsenc.c  | 64 ---
> libavformat/hlsplaylist.c |  4 ++-
> libavformat/hlsplaylist.h |  2 +-
> 5 files changed, 79 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.
> +@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
> +@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 5687530..f363418 100644
> --- a/libavformat/dashenc.c
> +++ b/libavformat/dashenc.c
> @@ -759,7 +759,8 @@ 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 e3442c3..53dc835 100644
> --- a/libavformat/hlsenc.c
> +++ b/libavformat/hlsenc.c
> @@ -144,6 +144,7 @@ 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;
> 
> @@ -1085,7 +1086,7 @@ 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;
>AVDictionary *options = NULL;
>unsigned int i, j;
> @@ -1117,6 +1118,34 @@ static int create_master_playlist(AVFormatContext *s,
> 
>ff_hls_write_playlist_version(hls->m3u8_out, 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(hls->m3u8_out, 
> "#EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID=\"group_%s\"",
> +vs->agroup);
> +avio_printf(hls->m3u8_out, 
> ",NAME=\"audio_0\",DEFAULT=YES,URI=\"%s\"\n",
> +m3u8_rel_name);
> +av_freep(_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]);
> @@ -1149,6 +1178,25 @@ 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 && 

[FFmpeg-devel] [PATCH v8 1/3] avformat/hlsenc:addition of #EXT-X-MEDIA tag and AUDIO attribute

[vdixit]

From: Vishwanath Dixit 

---
 doc/muxers.texi   | 12 +
 libavformat/dashenc.c |  3 ++-
 libavformat/hlsenc.c  | 64 ---
 libavformat/hlsplaylist.c |  4 ++-
 libavformat/hlsplaylist.h |  2 +-
 5 files changed, 79 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.
+@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
+@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 5687530..f363418 100644
--- a/libavformat/dashenc.c
+++ b/libavformat/dashenc.c
@@ -759,7 +759,8 @@ 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 e3442c3..53dc835 100644
--- a/libavformat/hlsenc.c
+++ b/libavformat/hlsenc.c
@@ -144,6 +144,7 @@ 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;
 
@@ -1085,7 +1086,7 @@ 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;
 AVDictionary *options = NULL;
 unsigned int i, j;
@@ -1117,6 +1118,34 @@ static int create_master_playlist(AVFormatContext *s,
 
 ff_hls_write_playlist_version(hls->m3u8_out, 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(hls->m3u8_out, 
"#EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID=\"group_%s\"",
+vs->agroup);
+avio_printf(hls->m3u8_out, 
",NAME=\"audio_0\",DEFAULT=YES,URI=\"%s\"\n",
+m3u8_rel_name);
+av_freep(_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]);
@@ -1149,6 +1178,25 @@ 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 &&
+!av_strcasecmp(temp_vs->agroup, vs->agroup)) {
+if (!aud_st)
+aud_st = temp_vs->streams[0];
+if