[FFmpeg-devel] [PATCH v1 3/4] avformat: add subtitle support in master playlist m3u8

Steven Liu lq at chinaffmpeg.org
Sun Mar 29 11:32:06 EEST 2020



> 2020年3月26日 下午9:56,lance.lmwang at gmail.com 写道:
> 
> From: Limin Wang <lance.lmwang at gmail.com>
> 
> Test with the following command for the webvtt subtitle:
> $ ./ffmpeg -y -i input_with_subtitle.mkv \
> -b:v:0 5250k -c:v h264 -pix_fmt yuv420p -profile:v main -level 4.1 \
> -b:a:0 256k \
> -c:s webvtt -c:a mp2 -ar 48000 -ac 2 -map 0:v -map 0:a:0 -map 0:s:0 \
> -f hls -var_stream_map "v:0,a:0,s:0,sgroup:subtitle” \
What about add the example into doc/muxer.texi ?
> -master_pl_name master.m3u8 -t 300 -hls_time 10 -hls_init_time 4 -hls_list_size \
> 10 -master_pl_publish_rate 10  -hls_flags \
> delete_segments+discont_start+split_by_time ./tmp/video.m3u8
> 
> Check the master m3u8:
> $ cat tmp/master.m3u8
> #EXTM3U
> #EXT-X-VERSION:3
> #EXT-X-MEDIA:TYPE=SUBTITLES,GROUP-ID="subtitle",NAME="subtitle_0",DEFAULT=YES,URI="video_vtt.m3u8"
> #EXT-X-STREAM-INF:BANDWIDTH=6056600,RESOLUTION=1280x720,CODECS="avc1.4d4829,mp4a.40.33",SUBTITLES="subtitle"
> video.m3u8
> 
> Check the result by convert to mkv:
> $ ./ffmpeg -strict experimental -i ./tmp/master.m3u8 -c:v copy -c:a mp2 -c:s srt ./test.mkv
> 
> Signed-off-by: Limin Wang <lance.lmwang at gmail.com>
> ---
> libavformat/dashenc.c     |  2 +-
> libavformat/hlsenc.c      | 26 ++++++++++++++++++++++++--
> libavformat/hlsplaylist.c | 17 ++++++++++++++++-
> libavformat/hlsplaylist.h |  4 +++-
> 4 files changed, 44 insertions(+), 5 deletions(-)
> 
> diff --git a/libavformat/dashenc.c b/libavformat/dashenc.c
> index 94d463972a..d1fe90b00c 100644
> --- a/libavformat/dashenc.c
> +++ b/libavformat/dashenc.c
> @@ -1311,7 +1311,7 @@ static int write_manifest(AVFormatContext *s, int final)
>             get_hls_playlist_name(playlist_file, sizeof(playlist_file), NULL, i);
>             ff_hls_write_stream_info(st, c->m3u8_out, stream_bitrate,
>                                      playlist_file, agroup,
> -                                     codec_str_ptr, NULL);
> +                                     codec_str_ptr, NULL, NULL);
>         }
>         dashenc_io_close(s, &c->m3u8_out, temp_filename);
>         if (use_rename)
> diff --git a/libavformat/hlsenc.c b/libavformat/hlsenc.c
> index a0a3a4647b..d7b9c0e20a 100644
> --- a/libavformat/hlsenc.c
> +++ b/libavformat/hlsenc.c
> @@ -164,6 +164,7 @@ typedef struct VariantStream {
>     int is_default; /* default status of audio group */
>     char *language; /* audio lauguage name */
>     char *agroup; /* audio group name */
> +    char *sgroup; /* subtitle group name */
>     char *ccgroup; /* closed caption group name */
>     char *baseurl;
>     char *varname; // variant name
> @@ -1289,7 +1290,9 @@ static int create_master_playlist(AVFormatContext *s,
>     unsigned int i, j;
>     int ret, bandwidth;
>     const char *m3u8_rel_name = NULL;
> +    const char *vtt_m3u8_rel_name = NULL;
>     char *ccgroup;
> +    char *sgroup = NULL;
>     ClosedCaptionsStream *ccs;
>     const char *proto = avio_find_protocol_name(hls->master_m3u8_url);
>     int is_file_proto = proto && !strcmp(proto, "file");
> @@ -1412,13 +1415,24 @@ static int create_master_playlist(AVFormatContext *s,
>                         vs->ccgroup);
>         }
> 
> +        if (vid_st && vs->sgroup) {
> +            sgroup = vs->sgroup;
> +            vtt_m3u8_rel_name = get_relative_url(hls->master_m3u8_url, vs->vtt_m3u8_name);
> +            if (!vtt_m3u8_rel_name) {
> +                av_log(s, AV_LOG_WARNING, "Unable to find relative subtitle URL\n");
> +                break;
> +            }
> +
> +            ff_hls_write_subtitle_rendition(hls->m3u8_out, sgroup, vtt_m3u8_rel_name, vs->language, i, hls->has_default_key ? vs->is_default : 1);
> +        }
> +
>         if (!hls->has_default_key || !hls->has_video_m3u8) {
>             ff_hls_write_stream_info(vid_st, hls->m3u8_out, bandwidth, m3u8_rel_name,
> -                    aud_st ? vs->agroup : NULL, vs->codec_attr, ccgroup);
> +                    aud_st ? vs->agroup : NULL, vs->codec_attr, ccgroup, sgroup);
>         } else {
>             if (vid_st) {
>                 ff_hls_write_stream_info(vid_st, hls->m3u8_out, bandwidth, m3u8_rel_name,
> -                                         aud_st ? vs->agroup : NULL, vs->codec_attr, ccgroup);
> +                                         aud_st ? vs->agroup : NULL, vs->codec_attr, ccgroup, sgroup);
>             }
>         }
>     }
> @@ -1893,6 +1907,7 @@ static int parse_variant_stream_mapstring(AVFormatContext *s)
>      * practical usage)
>      *
>      * agroup: is key to specify audio group. A string can be given as value.
> +     * sgroup: is key to specify subtitle group. A string can be given as value.
>      */
>     p = av_strdup(hls->var_stream_map);
>     if (!p)
> @@ -1960,6 +1975,12 @@ static int parse_variant_stream_mapstring(AVFormatContext *s)
>                 if (!vs->agroup)
>                     return AVERROR(ENOMEM);
>                 continue;
> +            } else if (av_strstart(keyval, "sgroup:", &val)) {
> +                av_free(vs->sgroup);
> +                vs->sgroup = av_strdup(val);
> +                if (!vs->sgroup)
> +                    return AVERROR(ENOMEM);
> +                continue;
>             } else if (av_strstart(keyval, "ccgroup:", &val)) {
>                 av_free(vs->ccgroup);
>                 vs->ccgroup = av_strdup(val);
> @@ -2516,6 +2537,7 @@ static void hls_free_variant_streams(struct HLSContext *hls)
>         av_freep(&vs->m3u8_name);
>         av_freep(&vs->streams);
>         av_freep(&vs->agroup);
> +        av_freep(&vs->sgroup);
>         av_freep(&vs->language);
>         av_freep(&vs->ccgroup);
>         av_freep(&vs->baseurl);
> diff --git a/libavformat/hlsplaylist.c b/libavformat/hlsplaylist.c
> index 56244496c0..43f9d281ba 100644
> --- a/libavformat/hlsplaylist.c
> +++ b/libavformat/hlsplaylist.c
> @@ -48,9 +48,22 @@ void ff_hls_write_audio_rendition(AVIOContext *out, char *agroup,
>     avio_printf(out, "URI=\"%s\"\n", filename);
> }
> 
> +void ff_hls_write_subtitle_rendition(AVIOContext *out, char *sgroup,
> +                                  const char *filename, char *language, int name_id, int is_default) {
> +    if (!out || !filename)
> +        return;
> +
> +    avio_printf(out, "#EXT-X-MEDIA:TYPE=SUBTITLES,GROUP-ID=\"%s\"", sgroup);
> +    avio_printf(out, ",NAME=\"subtitle_%d\",DEFAULT=%s,", name_id, is_default ? "YES" : "NO");
> +    if (language) {
> +        avio_printf(out, "LANGUAGE=\"%s\",", language);
> +    }
> +    avio_printf(out, "URI=\"%s\"\n", filename);
> +}
> +
> void ff_hls_write_stream_info(AVStream *st, AVIOContext *out,
>                               int bandwidth, const char *filename, char *agroup,
> -                              char *codecs, char *ccgroup) {
> +                              char *codecs, char *ccgroup, char *sgroup) {
> 
>     if (!out || !filename)
>         return;
> @@ -71,6 +84,8 @@ void ff_hls_write_stream_info(AVStream *st, AVIOContext *out,
>         avio_printf(out, ",AUDIO=\"group_%s\"", agroup);
>     if (ccgroup && ccgroup[0])
>         avio_printf(out, ",CLOSED-CAPTIONS=\"%s\"", ccgroup);
> +    if (sgroup && sgroup[0])
> +        avio_printf(out, ",SUBTITLES=\"%s\"", sgroup);
>     avio_printf(out, "\n%s\n\n", filename);
> }
> 
> diff --git a/libavformat/hlsplaylist.h b/libavformat/hlsplaylist.h
> index a8d29d62d3..a124bdcffb 100644
> --- a/libavformat/hlsplaylist.h
> +++ b/libavformat/hlsplaylist.h
> @@ -39,9 +39,11 @@ typedef enum {
> void ff_hls_write_playlist_version(AVIOContext *out, int version);
> void ff_hls_write_audio_rendition(AVIOContext *out, char *agroup,
>                                   const char *filename, char *language, int name_id, int is_default);
> +void ff_hls_write_subtitle_rendition(AVIOContext *out, char *sgroup,
> +                                  const char *filename, char *language, int name_id, int is_default);
> void ff_hls_write_stream_info(AVStream *st, AVIOContext *out,
>                               int bandwidth, const char *filename, char *agroup,
> -                              char *codecs, char *ccgroup);
> +                              char *codecs, char *ccgroup, char *sgroup);
> void ff_hls_write_playlist_header(AVIOContext *out, int version, int allowcache,
>                                   int target_duration, int64_t sequence,
>                                   uint32_t playlist_type, int iframe_mode);
> -- 
> 2.21.0
> 
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
> 
> To unsubscribe, visit link above, or email
> ffmpeg-devel-request at ffmpeg.org with subject "unsubscribe".

Thanks

Steven Liu





More information about the ffmpeg-devel mailing list