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• Where are there working exdamples for QSV enabled ffmpeg filters ?

  2 août 2021, par Bart Lederman

  I'm re-posting this question in a modified form because I'm told that stack overflow doesn't allow anyone to ask for the location of documentation. So now I'm not asking for documentation, I just want working examples of how the QSV enabled filters are used, with a specific question on why async doesn't work with vpp_qsv .

  


  I have a PC running Windows which is QSV capable. I've found the codec and at least one QSV filter which really speed up decoding and encoding AVC (x264) videos.

  


  But the experience is extremely aggravating, as I cannot find a list anywhere that I can find on what the filters and arguments actually are.

  


  The closest I've come for vpp_qsv is this :

  


  https://github.com/FFmpeg/FFmpeg/blob/master/libavfilter/vf_vpp_qsv.c

  


  It's a good start, but it has no examples of what the arguments actually are.
Source code doesn't explain how the filters actually work. However, this source code does say that async_depth is a valid qualifier.

  


  The few examples I've been able to find in various places (including stackoverflow) do not work.

  


  By experimentation, I've found that this works :

  


  ffmpeg -hide_banner -init_hw_device qsv=qsv -hwaccel qsv -i "input.mts" -c:a aac -c:v h264_qsv -preset veryslow -vf "vpp_qsv=cw=628:cx=0:w=640:h=480" -q:v 30 "output.mp4"

  


  I can add other things to the filter. For example :

  


  "vpp_qsv=deinterlace=2:cw=628:cx=0:w=640:h=480"

  


  will work. However, this will NOT work :

  


  "vpp_qsv=cw=628:cx=0:w=640:h=480:async_depth=4"

  


  even though there are examples posted that say it will.

  


  [Parsed_vpp_qsv_0 @ 0000000005bff8c0] Option 'async_depth' not found [AVFilterGraph @ 0000000007327dc0] Error initializing filter 'vpp_qsv' with args 'cw=628:cx=0:w=640:h=480:async_depth=4' Error reinitializing filters ! Failed to inject frame into filter network : Option not found Error while processing the decoded data for stream #0:0

  


  I also have been unable to find good examples of using more than one QSV enabled filter at the same time.

  


  I'm using the newest version of ffmpeg I can find :

  


  I :\ffmpeg -version ffmpeg version 4.4-full_build-www.gyan.dev Copyright (c) 2000-2021 the FFmpeg developers built with gcc 10.2.0 (Rev6, Built by MSYS2 project) configuration : —enable-gpl —enable-version3 —enable-static —disable-w32threads —disable-autodetect —enable-fontconfig —enable-iconv —enable-gnutls —enable-libxml 2 —enable-gmp —enable-lzma —enable-libsnappy —enable-zlib —enable-librist —enable-libsrt —enable-libssh —enable-libzmq —enable-avisynth —enable-libbluray —enab le-libcaca —enable-sdl2 —enable-libdav1d —enable-libzvbi —enable-librav1e —enable-libsvtav1 —enable-libwebp —enable-libx264 —enable-libx265 —enable-libxvid —ena ble-libaom —enable-libopenjpeg —enable-libvpx —enable-libass —enable-frei0r —enable-libfreetype —enable-libfribidi —enable-libvidstab —enable-libvmaf —enable-lib zimg —enable-amf —enable-cuda-llvm —enable-cuvid —enable-ffnvcodec —enable-nvdec —enable-nvenc —enable-d3d11va —enable-dxva2 —enable-libmfx —enable-libglslang - -enable-vulkan —enable-opencl —enable-libcdio —enable-libgme —enable-libmodplug —enable-libopenmpt —enable-libopencore-amrwb —enable-libmp3lame —enable-libshine - -enable-libtheora —enable-libtwolame —enable-libvo-amrwbenc —enable-libilbc —enable-libgsm —enable-libopencore-amrnb —enable-libopus —enable-libspeex —enable-libv orbis —enable-ladspa —enable-libbs2b —enable-libflite —enable-libmysofa —enable-librubberband —enable-libsoxr —enable-chromaprint libavutil 56. 70.100 / 56. 70.100 libavcodec 58.134.100 / 58.134.100 libavformat 58. 76.100 / 58. 76.100 libavdevice 58. 13.100 / 58. 13.100 libavfilter 7.110.100 / 7.110.100 libswscale 5. 9.100 / 5. 9.100 libswresample 3. 9.100 / 3. 9.100 libpostproc 55. 9.100 / 55. 9.100

  


  and the output of "ffmpeg -filters" says I have the various QSV enabled filters on my system.

  


  I have searched dozens and dozens of sites including Intel and ffmpeg.org and I cannot find a clear explanation of how the various QSV enabled filters work, with examples that will actually execute on my system. Could someone please point me to where this filter is explained ? (This is NOT, I repeat, NOT a banned request for documentation. I'm asking how to use a specific qualifier in a specific filter.)

  


• Video Conferencing in HTML5 : WebRTC via Socket.io

  
  5 février 2013, par silvia

  Six months ago I experimented with Web sockets for WebRTC and the early implementations of PeerConnection in Chrome. Last week I gave a presentation about WebRTC at Linux.conf.au, so it was time to update that codebase.

  I decided to use socket.io for the signalling following the idea of Luc, which made the server code even smaller and reduced it to a mere reflector :

   var app = require(’http’).createServer().listen(1337) ;
   var io = require(’socket.io’).listen(app) ;
   io.sockets.on(’connection’, function(socket) 
  
           socket.on(’message’, function(message) 
  
           socket.broadcast.emit(’message’, message) ;
  
       ) ;
  
   ) ;
  

  Then I turned to the client code. I was surprised to see the massive changes that PeerConnection has gone through. Check out my slide deck to see the different components that are now necessary to create a PeerConnection.

  I was particularly surprised to see the SDP object now fully exposed to JavaScript and thus the ability to manipulate it directly rather than through some API. This allows Web developers to manipulate the type of session that they are asking the browsers to set up. I can imaging e.g. if they have support for a video codec in JavaScript that the browser does not provide built-in, they can add that codec to the set of choices to be offered to the peer. While it is flexible, I am concerned if this might create more problems than it solves. I guess we’ll have to wait and see.

  I was also surprised by the need to use ICE, even though in my experiment I got away with an empty list of ICE servers – the ICE messages just got exchanged through the socket.io server. I am not sure whether this is a bug, but I was very happy about it because it meant I could run the whole demo on a completely separate network from the Internet.

  The most exciting news since my talk is that Mozilla and Google have managed to get a PeerConnection working between Firefox and Chrome – this is the first cross-browser video conference call without a plugin ! The code differences are minor.

  Since the specification of the WebRTC API and of the MediaStream API are now official Working Drafts at the W3C, I expect other browsers will follow. I am also looking forward to the possibilities of :

  • multi-peer video conferencing like the efforts around webrtc.io,
  • the media stream recording API,
  • and the peer-to-peer data API.

  The best places to learn about the latest possibilities of WebRTC are webrtc.org and the W3C WebRTC WG. code.google.com has open source code that continues to be updated to the latest released and interoperable features in browsers.

  The video of my talk is in the process of being published. There is a MP4 version on the Linux Australia mirror server, but I expect it will be published properly soon. I will update the blog post when that happens.

• Video Conferencing in HTML5 : WebRTC via Socket.io

  
  1er janvier 2014, par silvia

  Six months ago I experimented with Web sockets for WebRTC and the early implementations of PeerConnection in Chrome. Last week I gave a presentation about WebRTC at Linux.conf.au, so it was time to update that codebase.

  I decided to use socket.io for the signalling following the idea of Luc, which made the server code even smaller and reduced it to a mere reflector :

   var app = require(’http’).createServer().listen(1337) ;
   var io = require(’socket.io’).listen(app) ;
   io.sockets.on(’connection’, function(socket) 
  
           socket.on(’message’, function(message) 
  
           socket.broadcast.emit(’message’, message) ;
  
       ) ;
  
   ) ;
  

  Then I turned to the client code. I was surprised to see the massive changes that PeerConnection has gone through. Check out my slide deck to see the different components that are now necessary to create a PeerConnection.

  I was particularly surprised to see the SDP object now fully exposed to JavaScript and thus the ability to manipulate it directly rather than through some API. This allows Web developers to manipulate the type of session that they are asking the browsers to set up. I can imaging e.g. if they have support for a video codec in JavaScript that the browser does not provide built-in, they can add that codec to the set of choices to be offered to the peer. While it is flexible, I am concerned if this might create more problems than it solves. I guess we’ll have to wait and see.

  I was also surprised by the need to use ICE, even though in my experiment I got away with an empty list of ICE servers – the ICE messages just got exchanged through the socket.io server. I am not sure whether this is a bug, but I was very happy about it because it meant I could run the whole demo on a completely separate network from the Internet.

  The most exciting news since my talk is that Mozilla and Google have managed to get a PeerConnection working between Firefox and Chrome – this is the first cross-browser video conference call without a plugin ! The code differences are minor.

  Since the specification of the WebRTC API and of the MediaStream API are now official Working Drafts at the W3C, I expect other browsers will follow. I am also looking forward to the possibilities of :

  • multi-peer video conferencing like the efforts around webrtc.io,
  • the media stream recording API,
  • and the peer-to-peer data API.

  The best places to learn about the latest possibilities of WebRTC are webrtc.org and the W3C WebRTC WG. code.google.com has open source code that continues to be updated to the latest released and interoperable features in browsers.

  The video of my talk is in the process of being published. There is a MP4 version on the Linux Australia mirror server, but I expect it will be published properly soon. I will update the blog post when that happens.