Sur d’autres sites (4667)

• How to specify MPEG-DASH adaptation sets in FFmpeg, when using optional output audio and subtitle streams ?

  15 juillet 2021, par Sebsii

  I am using the script below to transform videos to MPEG-DASH compliant ones. I want also to be able to process video that have no audio and/or no subtitles. Because of that I marked the streams for audio and subtitles with a ? at the end of the stream specifier, f.e. -map a:0?.

  


  Now when I want to specify the adaptation sets I can set it for the video and audio streams with id=0,streams=v and id=1,streams=a, but I can not select the subtitle streams, like I would want to with id=2,streams=s, as it is stated in the docs ("To map all video (or audio) streams to an AdaptationSet, "v" (or "a") can be used as stream identifier instead of IDs."). The only thing I could do is to specify an ID, like id=2,streams=8, but for that to work, an audio and subtitle stream would be mandatory, because otherwise there is no stream with the id 8 and FFmpeg would fail. I thought of putting the -map s:0? at the first position, then I could be sure, that it is always the stream with id 0, but if the input did not have a subtitle stream, then there would be an additional adaptation set, with the first version of video. I also thought about using FFprobe to get info about the available streams, but did not look too much into depth.

  


  Does anybody know how I could tell FFmpeg, that an adaptation set should be created, when there's a stream with subtitles present independent of there being audio streams or not ?

  


  Any help is much appreciated.

  


  #!/bin/bash

INPUT_PATH=$1
OUTPUT_PATH=$2

FPS=25
GOP_SIZE=100
PRESET_P=veryfast
V_SIZE_1=256x144
V_SIZE_2=426x240
V_SIZE_3=640x360
V_SIZE_4=854x480
V_SIZE_5=1280x720
V_SIZE_6=1920x1080

ffmpeg -i "$INPUT_PATH" \
    -preset $PRESET_P -keyint_min $GOP_SIZE -g $GOP_SIZE -sc_threshold 0 \
    -r $FPS -c:v libx264 -pix_fmt yuv420p -c:a aac -c:s copy \
    -map v:0 -s:0 $V_SIZE_1 -b:v:0 160k -maxrate:0 160k -bufsize:0 320k \
    -map v:0 -s:1 $V_SIZE_2 -b:v:1 450k -maxrate:1 450k -bufsize:1 900k \
    -map v:0 -s:2 $V_SIZE_3 -b:v:2 1M -maxrate:2 1M -bufsize:2 2M \
    -map v:0 -s:3 $V_SIZE_4 -b:v:3 2.5M -maxrate:3 2.5M -bufsize:3 5M \
    -map v:0 -s:4 $V_SIZE_5 -b:v:4 5M -maxrate:4 5M -bufsize:4 10M \
    -map v:0 -s:5 $V_SIZE_6 -b:v:5 8M -maxrate:5 8M -bufsize:5 16M \
    -map a:0? -b:a:0 128k -ac:a:0 1 \
    -map a:0? -b:a:1 384k -ac:a:1 2 \
    -map s:0? \
    -use_template 1 -use_timeline 1  \
    -seg_duration 4 -adaptation_sets "id=0,streams=v id=1,streams=a id=2,streams=s" \
    -f dash "$OUTPUT_PATH"


  


• Serving static video content directly vs. via adaptive streaming protocols (HLS, DASH)

  7 mai 2020, par astralmaster

  Is there an advantage of serving static video content (not a live stream) via adaptive streaming protocols such as HLS or DASH over serving them directly as files using HTTP server in terms of speed ?

  



  Example case is when you have a 500MB mp4 h264+AAC video that you have to serve on a website via HTML5 video element. Would you rather serve it directly, since most popular browsers implement functions such as seek without downloading the whole file first ; or would you rather use ffmpeg or similar solution to create HLS chunks from the mp4 file and instead provide .m3u8 playlist source to the HTML5 video element. Is there a real advantage in terms of speed of doing this ?

  



  Which one would you implement if you had hundreds of video files all served as static content ?

  


• Dash.js not playing mpd files made with ffmpeg

  31 décembre 2022, par Macster

  I'm using ffmpeg to create chunks and manifest of a webm file which I want to live stream with Dash.js. Unfortunately Dash.js won't play the mpd file, no matter which way I create the chunks and manifest. However, the sample mpd URL from Dash.js is working.

  


  Commands

  


  ffmpeg -re -r 25 -i Dash/strm.webm
-map 0:v:0
-pix_fmt yuv420p
-c:v libvpx
-s 640x480 -keyint_min 60 -g 60 -speed 6 -tile-columns 4 -frame-parallel 1 -threads 8 -static-thresh 0 -max-intra-rate 300 -deadline realtime -lag-in-frames 0 -error-resilient 1
-b:v 3000k
-f webm_chunk
-header "Dash/glass_360.hdr"
-chunk_start_index 1 Dash/glass_360_%d.chk
-map 0:a:0
-c:a libvorbis
-b:a 128k -ar 44100
-f webm_chunk
-audio_chunk_duration 2000
-header Dash/glass_171.hdr
-chunk_start_index 1 Dash/glass_171_%d.chk


//Manifest
ffmpeg
-f webm_dash_manifest -live 1
-i Dash/glass_360.hdr
-f webm_dash_manifest -live 1
-i Dash/glass_171.hdr
-c copy
-map 0 -map 1
-f webm_dash_manifest -live 1
-adaptation_sets "id=0,streams=0 id=1,streams=1"
-chunk_start_index 1
-chunk_duration_ms 2000
-time_shift_buffer_depth 7200
-minimum_update_period 7200 Dash/glass_video_manifest.mpd


  


  Manifest output

  


  ffmpeg version git-2020-05-27-8b5ffae Copyright (c) 2000-2020 the FFmpeg developers
  built with gcc 9.3.1 (GCC) 20200523
  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-libsrt --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-libvmaf --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --disable-w32threads --enable-libmfx --enable-ffnvcodec --enable-cuda-llvm --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt --enable-amf
  libavutil      56. 49.100 / 56. 49.100
  libavcodec     58. 87.101 / 58. 87.101
  libavformat    58. 43.100 / 58. 43.100
  libavdevice    58.  9.103 / 58.  9.103
  libavfilter     7. 83.100 /  7. 83.100
  libswscale      5.  6.101 /  5.  6.101
  libswresample   3.  6.100 /  3.  6.100
  libpostproc    55.  6.100 / 55.  6.100
Input #0, webm_dash_manifest, from 'Dash/glass_360.hdr':
  Metadata:
    ENCODER         : Lavf58.43.100
  Duration: N/A, bitrate: N/A
    Stream #0:0(eng): Video: vp8, yuv420p, 640x480, SAR 1:1 DAR 4:3, 1k tbr, 1k tbn, 1k tbc (default)
    Metadata:
      ALPHA_MODE      : 1
      ENCODER         : Lavc58.87.101 libvpx
      webm_dash_manifest_file_name: glass_360.hdr
      webm_dash_manifest_track_number: 1
Input #1, webm_dash_manifest, from 'Dash/glass_171.hdr':
  Metadata:
    ENCODER         : Lavf58.43.100
  Duration: N/A, bitrate: N/A
    Stream #1:0(eng): Audio: vorbis, 44100 Hz, mono, fltp (default)
    Metadata:
      ENCODER         : Lavc58.87.101 libvorbis
      webm_dash_manifest_file_name: glass_171.hdr
      webm_dash_manifest_track_number: 1
Output #0, webm_dash_manifest, to 'Dash/glass_video_manifest.mpd':
  Metadata:
    encoder         : Lavf58.43.100
    Stream #0:0(eng): Video: vp8, yuv420p, 640x480 [SAR 1:1 DAR 4:3], q=2-31, 1k tbr, 1k tbn, 1k tbc (default)
    Metadata:
      ALPHA_MODE      : 1
      ENCODER         : Lavc58.87.101 libvpx
      webm_dash_manifest_file_name: glass_360.hdr
      webm_dash_manifest_track_number: 1
    Stream #0:1(eng): Audio: vorbis, 44100 Hz, mono, fltp (default)
    Metadata:
      ENCODER         : Lavc58.87.101 libvorbis
      webm_dash_manifest_file_name: glass_171.hdr
      webm_dash_manifest_track_number: 1
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
  Stream #1:0 -> #0:1 (copy)
Press [q] to stop, [?] for help
frame=    0 fps=0.0 q=-1.0 Lsize=       1kB time=00:00:00.00 bitrate=N/A speed=   0x
video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:4kB muxing overhead: unknown


  


  Manifest file
  (glass_video_manifest.mpd)
  
I tried to delete the ContetntComponent like suggested in other questions, but it didn't work.

  


  &lt;?xml version="1.0" encoding="UTF-8"?>&#xA;&#xA;<period start="PT0S">&#xA;<adaptationset mimetype="video/webm" codecs="vp8" lang="eng" bitstreamswitching="true" subsegmentalignment="true" subsegmentstartswithsap="1">&#xA;<contentcomponent type="video"></contentcomponent>&#xA;<segmenttemplate timescale="1000" duration="2000" media="glass_$RepresentationID$_$Number$.chk" startnumber="1" initialization="glass_$RepresentationID$.hdr"></segmenttemplate>&#xA;<representation bandwidth="1000000" width="640" height="480" codecs="vp8" mimetype="video/webm" startswithsap="1"></representation>&#xA;</adaptationset>&#xA;<adaptationset mimetype="audio/webm" codecs="vorbis" lang="eng" bitstreamswitching="true" subsegmentalignment="true" subsegmentstartswithsap="1">&#xA;<contentcomponent type="audio"></contentcomponent>&#xA;<segmenttemplate timescale="1000" duration="2000" media="glass_$RepresentationID$_$Number$.chk" startnumber="1" initialization="glass_$RepresentationID$.hdr"></segmenttemplate>&#xA;<representation bandwidth="128000" audiosamplingrate="44100" codecs="vorbis" mimetype="audio/webm" startswithsap="1"></representation>&#xA;</adaptationset>&#xA;</period>&#xA;&#xA;

  


  Dash.js-Player

  


  <code class="echappe-js">&lt;script&gt;&amp;#xA;&amp;#xA;(function(){&amp;#xA;  // var url = &quot;https://dash.akamaized.net/envivio/EnvivioDash3/manifest.mpd&quot;;&amp;#xA;  var url = &quot;http://localhost:8081/videos/Dash/glass_live_manifest.mpd&quot;;&amp;#xA;  var player = dashjs.MediaPlayer().create();&amp;#xA;                &amp;#xA;  // config&amp;#xA;  targetLatency = 2.0;        // Lowering this value will lower latency but may decrease the player&amp;#x27;s ability to build a stable buffer.&amp;#xA;  minDrift = 0.05;            // Minimum latency deviation allowed before activating catch-up mechanism.&amp;#xA;  catchupPlaybackRate = 0.5;  // Maximum catch-up rate, as a percentage, for low latency live streams.&amp;#xA;  stableBuffer = 2;           // The time that the internal buffer target will be set to post startup/seeks (NOT top quality).&amp;#xA;  bufferAtTopQuality = 2;     // The time that the internal buffer target will be set to once playing the top quality.&amp;#xA;&amp;#xA;   player.updateSettings({&amp;#xA;      &amp;#x27;streaming&amp;#x27;: {&amp;#xA;          &amp;#x27;liveDelay&amp;#x27;: 2,&amp;#xA;          &amp;#x27;liveCatchUpMinDrift&amp;#x27;: 0.05,&amp;#xA;          &amp;#x27;liveCatchUpPlaybackRate&amp;#x27;: 0.5,&amp;#xA;          &amp;#x27;stableBufferTime&amp;#x27;: 2,&amp;#xA;          &amp;#x27;bufferTimeAtTopQuality&amp;#x27;: 2,&amp;#xA;          &amp;#x27;bufferTimeAtTopQualityLongForm&amp;#x27;: 2,&amp;#xA;          &amp;#x27;bufferToKeep&amp;#x27;: 2,&amp;#xA;          &amp;#x27;bufferAheadToKeep&amp;#x27;: 2,&amp;#xA;          &amp;#x27;lowLatencyEnabled&amp;#x27;: true,&amp;#xA;          &amp;#x27;fastSwitchEnabled&amp;#x27;: true,&amp;#xA;          &amp;#x27;abr&amp;#x27;: {&amp;#xA;               &amp;#x27;limitBitrateByPortal&amp;#x27;: true&amp;#xA;          },&amp;#xA;       }&amp;#xA;   });&amp;#xA;&amp;#xA;   console.log(player.getSettings());&amp;#xA;&amp;#xA;   setInterval(() =&gt; {&amp;#xA;      console.log(&amp;#x27;Live latency= &amp;#x27;, player.getCurrentLiveLatency());&amp;#xA;      console.log(&amp;#x27;Buffer length= &amp;#x27;, player.getBufferLength(&amp;#x27;video&amp;#x27;));&amp;#xA;     }, 3000);&amp;#xA;&amp;#xA;     player.initialize(document.querySelector(&quot;#videoPlayer&quot;), url, true);&amp;#xA;&amp;#xA;   })();&amp;#xA;&lt;/script&gt;&#xA;

  


  Chrome

  


  {debug: {…}, streaming: {…}}
dash.all.min.js:2 XHR finished loading: GET "http://localhost:8081/videos/Dash/glass_live_manifest.mpd".
load @ dash.all.min.js:2
C @ dash.all.min.js:2
load @ dash.all.min.js:2
load @ dash.all.min.js:2
load @ dash.all.min.js:2
load @ dash.all.min.js:2
se @ dash.all.min.js:2
te @ dash.all.min.js:2
initialize @ dash.all.min.js:2
(anonymous) @ Dash:92
(anonymous) @ Dash:94
DevTools failed to load SourceMap: Could not parse content for http://localhost:8081/js/dash.all.min.js.map: Cannot read property 'length' of undefined
Dash:88 Live latency=  NaN
Dash:89 Buffer length=  NaN
Dash:88 Live latency=  NaN
Dash:89 Buffer length=  NaN
Dash:88 Live latency=  NaN
Dash:89 Buffer length=  NaN
Dash:88 Live latency=  NaN
Dash:89 Buffer length=  NaN
Dash:88 Live latency=  NaN
Dash:89 Buffer length=  NaN


  


  UPDATE

  


  Well, it seems like the problem in general was, that the mpd's wouldn't play from that /dash folder. So i took a look into the code and found a bad routing. Anyways, the mpd would't start with the given command I used, probably becasue it creates a dynamic manifest, like @Markus Schumann says. So I'm going with a new one which seems to be working for now, but not very well.

  


  ffmpeg -y -re -i strm.webm 
-c:v libx264 -x264opts "keyint=24:min-keyint=24:no-scenecut" 
-r 24 -c:a aac -b:a 128k -bf 1 -b_strategy 0 -sc_threshold 0 -pix_fmt yuv420p 
-map 0:v:0 -map 0:a:0 -map 0:v:0 -map 0:a:0 -map 0:v:0 -map 0:a:0 -b:v:0 250k  
-filter:v:0 "scale=-2:240" -profile:v:0 baseline -b:v:1 750k  
-filter:v:1 "scale=-2:480" -profile:v:1 main -b:v:2 1500k 
-filter:v:2 "scale=-2:720" -profile:v:2 high 
-use_timeline 1 -use_template 1 -window_size 5 -adaptation_sets "id=0,streams=v id=1,streams=a" 
-f dash glass_video_manifest.mpd