Migrate from NGINX-RTMP, support HLS variant, multiple bitrate, HLS multi-bitrate

[winlinvip]

https://github.com/arut/nginx-rtmp-module/wiki/Directives#hls_variant
NGINX-RTMP matches several stream names and then generates a single HLS multi-bitrate stream.

TRANS_BY_GPT3

[mbeacom]

@winlinvip Is this something you're looking for contributions on or do you plan to write this yourself? Thanks for everything!

[winlinvip]

Both are ok.

[jpransxdev]

This would be crazy useful. I stumbled upon SRS and was very excited but with no support for HLS variants SRS does not fit my use case :) Unfortunately am unable to contribute to this :(

[winlinvip]

Plan in SRS4.

[jb-alvarado]

For people how needs this feature: you can realize this now already with srs:

• prepare your defaultVhost with transcoding:

transcode live/stream {
        enabled     on;
        ffmpeg      /usr/local/bin/ffmpeg;
        engine half {
            enabled         on;
            iformat         live_flv;
            vfilter {
                v           quiet;
            }

            vcodec          libx264;
            vfps            25;
            vwidth          512;
            vheight         288;
            vprofile        main;
            vpreset         medium;

            vparams {
                crf         23;
                x264opts    keyint=50:min-keyint=50:no-scenecut;
                maxrate     650k;
                bufsize     1300k;
            }

            acodec          copy;
            oformat         flv;
            output          rtmp://localhost:1935/live/half;
        }
    }

    hls {
        enabled         on;
        hls_path        /var/www/srs/live;
        hls_fragment    6;
        hls_window      1800;
        hls_cleanup     on;
        hls_dispose     5;
        hls_m3u8_file   [stream]_hq.m3u8;
        hls_ts_file     [stream]_hq-[seq].ts;
    }

• then add a second vhost for localhost and add there a new hls statement:

    hls {
        enabled         on;
        hls_path        /var/www/srs/live;
        hls_fragment    6;
        hls_window      1800;
        hls_cleanup     on;
        hls_dispose     5;
        hls_m3u8_file   [stream]_lq.m3u8;
        hls_ts_file     [stream]_lq-[seq].ts;
    }

• then create a master.m3u8:

#EXTM3U
#EXT-X-VERSION:3
#EXT-X-ALLOW-CACHE:YES
#EXT-X-MEDIA-SEQUENCE:0
#EXT-X-TARGETDURATION:15
#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=2149280,CODECS="mp4a.40.2,avc1.64001f",RESOLUTION=1024x576,NAME="1024"
live/stream_hq.m3u8
#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=460560,CODECS="mp4a.40.5,avc1.420016",RESOLUTION=512x288,NAME="512"
live/half_lq.m3u8

• set the correct BANDWIDTH

If you need more resolutions just add in transcode more outputs under vparams, maybe like this:

...
s           1024x576;
crf         23;
x264opts    keyint=50:min-keyint=50:no-scenecut;
maxrate     1300k;
bufsize     2600k;
f           flv;
c:a         copy;
y           rtmp://127.0.1.1:1935/live/big;
crf         23;
x264opts    keyint=50:min-keyint=50:no-scenecut;
maxrate     650k;
bufsize     1300k;
...

and add more vhosts.

Here is a working gist

[winlinvip]

@jb-alvarado 👍 Thanks! It's a better solution to use FFMPEG to transcode RTMP to multiple HLS streams.