Ingest no audio stream (HLS trouble)

[Mike K]

Hi. I use SRS 2.
When i catch my camera stream with no audio, on output from ingest i getting stream with audo "undf" codec and results HLS on mobile platforms doesnt work.

ffmoeg info HLS .ts file:
[NULL @ 0x237f1e0] start time for stream 0 is not set in estimate_timings_from_pts
[mpegts @ 0x237b420] Could not find codec parameters for stream 0 (Audio: aac ([15][0][0][0] / 0x000F), 0 channels, fltp): unspecified sample rate
Consider increasing the value for the 'analyzeduration' and 'probesize' options

Example of hls stream: http://cam.utl.ru/22/hls/live.m3u8

[Winlin]

HLS does not support video only.

[Winlin]

Maybe SRS should support this.

[Winlin]

Use SRS ingest to drop audio and output HLS:

vhost __defaultVhost__ {
    hls {
        enabled         on;
        hls_fragment    10;
        hls_window      60;
        hls_path        ./objs/nginx/html;
        hls_m3u8_file   [app]/[stream]/live.m3u8;
        hls_ts_file     [app]/[stream]/[timestamp].ts;
    }
    ingest livestream {
        enabled      on;
        input {
            type    file;
            url     doc/source.200kbps.768x320.flv;
        }
        ffmpeg      ./objs/ffmpeg/bin/ffmpeg;
        engine {
            enabled    on;
            vcodec copy;
            acodec an;
            output          rtmp://127.0.0.1:[port]/live?vhost=[vhost]/livestream;
        }
    }
}

Get the info of HLS:

winlin:livestream winlin$ ffmpeg -i live.m3u8 
    Stream #0:0: Audio: aac ([15][0][0][0] / 0x000F), 0 channels, fltp
    Stream #0:1: Video: h264 (High) ([27][0][0][0] / 0x001B), yuv420p, 768x320 [SAR 1:1 DAR 12:5], 25 fps, 25 tbr, 90k tbn, 50 tbc

There is no audio stream, but the HLS indicates the audio codec is AAC.

[Winlin]

This because the SRS never know the codec of video and audio when write the ts PAT/PMT info.
So we must set the vcodec and acodec of HLS:

        # the default audio codec of hls.
        # when codec changed, write the PAT/PMT table, but maybe ok util next ts.
        # so user can set the default codec for mp3.
        # the available audio codec:
        #       aac, mp3, an
        # default: aac
        hls_acodec      an;
        # the default video codec of hls.
        # when codec changed, write the PAT/PMT table, but maybe ok util next ts.
        # so user can set the default codec for pure audio(without video) to vn.
        # the available video codec:
        #       h264, vn
        # default: h264
        hls_vcodec      h264;

So, we change the config of SRS to:

vhost __defaultVhost__ {
    hls {
        enabled         on;
        hls_fragment    10;
        hls_window      60;
        hls_path        ./objs/nginx/html;
        hls_m3u8_file   [app]/[stream]/live.m3u8;
        hls_ts_file     [app]/[stream]/[timestamp].ts;
        hls_acodec      an;
        hls_vcodec      h264;
    }
    ingest livestream {
        enabled      on;
        input {
            type    file;
            url     doc/source.200kbps.768x320.flv;
        }
        ffmpeg      ./objs/ffmpeg/bin/ffmpeg;
        engine {
            enabled    on;
            vcodec copy;
            acodec an;
            output          rtmp://127.0.0.1:[port]/live?vhost=[vhost]/livestream;
        }
    }
}

And the info of SRS:

winlin:srs winlin$ ./objs/srs -v
2.0.172
winlin:livestream winlin$ ffmpeg -i live.m3u8 
    Stream #0:0: Video: h264 (High) ([27][0][0][0] / 0x001B), yuv420p, 768x320 [SAR 1:1 DAR 12:5], 25 fps, 25 tbr, 90k tbn, 50 tbc

And it's test ok on:

1. MAC safari.
2. MAC chrome, jwplayer.
3. MAC VLC.
4. Android 4.4