[FFmpeg-user] Using FFMpeg to produce LL-HLS

[Simon Brown]

>
>
>
> > Am 18.02.2020 um 17:24 schrieb Simon Brown <simon.k.brown at gmail.com>:
> >
> > Is the codec tag h264 different to what libx264 produces?  Is there a
> > reason it can't work with h264 codec tag?
>
> Contrary to what is sometimes claimed you have to read errors from top:
> The issue is apparently that the dash muxer requires to know the bitrate of
> the h264 stream.
>
> Carl Eugen
> _______________________________________________
>
> Thank you Carl.  I have now rejigged the command line to try and use ldash
instead of lhls, but am getting the same error, though now it's no longer
complaining about not having a bit rate because that is set.

C:\xampp\htdocs>\ffmpeg-20200216-8578433-win64-static\bin\ffmpeg.exe -i
udp://127.0.0.1:9034 -codec copy -b:v 6000k -window_size 5
-extra_window_size 5 -use_timeline 1 -seg_duration 1 -frag_duration 0.2
-streaming 1 -adaptation_sets "id=0,streams=v id=1,streams=a"
-dash_segment_type mp4 -ldash 1 -f dash manifest.mpd
ffmpeg version git-2020-02-16-8578433 Copyright (c) 2000-2020 the FFmpeg
developers
  built with gcc 9.2.1 (GCC) 20200122
  configuration: --enable-gpl --enable-version3 --enable-sdl2
--enable-fontconfig --enable-gnutls --enable-iconv --enable-libass
--enable-libdav1d --enable-libbluray --enable-libfreetype
--enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb
--enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy
--enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx
--enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265
--enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp
--enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc
--enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom
--enable-libmfx --enable-ffnvcodec --enable-cuvid --enable-d3d11va
--enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth
--enable-libopenmpt --enable-amf
  libavutil      56. 41.100 / 56. 41.100
  libavcodec     58. 70.100 / 58. 70.100
  libavformat    58. 38.101 / 58. 38.101
  libavdevice    58.  9.103 / 58.  9.103
  libavfilter     7. 76.100 /  7. 76.100
  libswscale      5.  6.100 /  5.  6.100
  libswresample   3.  6.100 /  3.  6.100
  libpostproc    55.  6.100 / 55.  6.100
Input #0, mpegts, from 'udp://127.0.0.1:9034':
  Duration: N/A, start: 82854.078300, bitrate: N/A
  Program 1
    Stream #0:0[0x1100]: Video: h264 (Main) ([27][0][0][0] / 0x001B),
yuv420p(tv, top first), 1920x1080 [SAR 1:1 DAR 16:9], 25 fps, 16.67 tbr,
90k tbn, 50 tbc
    Stream #0:1[0x1110]: Audio: aac (LC) ([15][0][0][0] / 0x000F), 48000
Hz, stereo, fltp, 192 kb/s
[dash @ 0000020ab5934040] Opening 'init-stream0.m4s' for writing
[mp4 @ 0000020ab4fbd040] Tag [27][0][0][0] incompatible with output codec
id '27' (avc1)
Could not write header for output file #0 (incorrect codec parameters ?):
Invalid data found when processing input
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
  Stream #0:1 -> #0:1 (copy)
    Last message repeated 1 times

If instead I try to reencode, the stream information is similar, but
different:
[dash @ 00000272b2bec140] Opening 'init-stream0.m4s' for writing
Output #0, dash, to 'manifest.mpd':
  Metadata:
    encoder         : Lavf58.38.101
    Stream #0:0: Video: h264 (libx264), yuv420p, 1920x1080 [SAR 1:1 DAR
16:9], q=-1--1, 6000 kb/s, 16.67 fps, 45k tbn, 16.67 tbc
    Metadata:
      encoder         : Lavc58.70.100 libx264
    Side data:
      cpb: bitrate max/min/avg: 0/0/6000000 buffer size: 0 vbv_delay: N/A
[
So h264 is ok, but Main/avc1 isn't.  But libx264 is ok.  Aren't these much
the same thing?  What do I need to do to my encoded stream to make the dash
muxer accept it?

Cheers,
Simon