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• Compression of a video with constant background

  28 juin 2017, par Spirou003

  (sorry if my english is bad, I can read it but I don’t write it quite well...)

  I want to compress some videos, which have two particularities :

  • there is a background that covers 90% of the area, during the whole video
  • most of the others elements can be separately described by a picture in move

  My videos are like this one, and don’t have audio. As you can see, almost everything can be described only by using a fixed background, few small images in move, plus a noise. Moreover, this noise will be almost nul and then an entropic coding would be very efficient. I think it will produce tiny files (< 5 Mo) even if the duration is in hours, a result that is very appreciable since I have actually recorded 30h of game (actual size is 3 Go).

  Is there any way to get new video files, that benefit of these informations ? If yes, what are the implication of a such encoding for watching these videos with Windows Media Player, or for usage with ffmpeg ?

  I searched with Google after anything that can help me, but I don’t know which keyword I can use for this, then I didn’t found anything usefull :-(

  Thanks in advance :-)

  PS : another example, the video is accelerated but shows the interesting moves

• Converting mp3 files to ogg vorbis while retaining cover art using FFmpeg

  22 juin 2017, par refi64

  Title says it all. I’ve tried :

  ffmpeg -i 01_FFXV_OST.mp3 -c:a libvorbis 01_FFXV_OST.ogg

  but I get :

  ffmpeg version git-2017-01-22-f1214ad Copyright (c) 2000-2017 the FFmpeg developers
  
    built with gcc 4.8 (Ubuntu 4.8.4-2ubuntu1~14.04.3)
  
    configuration: --extra-libs=-ldl --prefix=/opt/ffmpeg --mandir=/usr/share/man --enable-avresample --disable-debug --enable-nonfree --enable-gpl --enable-version3 --enable-libopencore-amrnb --enable-libopencore-amrwb --disable-decoder=amrnb --disable-decoder=amrwb --enable-libpulse --enable-libfreetype --enable-gnutls --enable-libx264 --enable-libx265 --enable-libfdk-aac --enable-libvorbis --enable-libmp3lame --enable-libopus --enable-libvpx --enable-libspeex --enable-libass --enable-avisynth --enable-libsoxr --enable-libxvid --enable-libvidstab --enable-libwavpack --enable-nvenc
  
    libavutil      55. 44.100 / 55. 44.100
  
    libavcodec     57. 75.100 / 57. 75.100
  
    libavformat    57. 63.100 / 57. 63.100
  
    libavdevice    57.  2.100 / 57.  2.100
  
    libavfilter     6. 69.100 /  6. 69.100
  
    libavresample   3.  2.  0 /  3.  2.  0
  
    libswscale      4.  3.101 /  4.  3.101
  
    libswresample   2.  4.100 /  2.  4.100
  
    libpostproc    54.  2.100 / 54.  2.100
  
  Input #0, mp3, from '01_FFXV_OST.mp3':
  
    Metadata:
  
      album           : FINAL FANTASY XV Original Soundtrack
  
      artist          : Yoko Shimomura
  
      album_artist    : SQUARE ENIX MUSIC
  
      composer        : Yoko Shimomura
  
      disc            : 1
  
      genre           : Game
  
      title           : Somnus (Instrumental Version)
  
      track           : 01
  
      date            : 2016
  
    Duration: 00:02:29.47, start: 0.023021, bitrate: 306 kb/s
  
      Stream #0:0: Audio: mp3, 48000 Hz, stereo, s16p, 301 kb/s
  
      Metadata:
  
        encoder         : LAME3.98r
  
      Stream #0:1: Video: mjpeg, yuvj444p(pc, bt470bg/unknown/unknown), 500x500 [SAR 100:100 DAR 1:1], 90k tbr, 90k tbn, 90k tbc
  
      Metadata:
  
        comment         : Cover (front)
  
  Automatic encoder selection failed for output stream #0:0. Default encoder for format ogg (codec theora) is probably disabled. Please choose an encoder manually.
  
  Error selecting an encoder for stream 0:0

  Adding on -c:v copy does...nothing :

  ffmpeg version git-2017-01-22-f1214ad Copyright (c) 2000-2017 the FFmpeg developers
  
    built with gcc 4.8 (Ubuntu 4.8.4-2ubuntu1~14.04.3)
  
    configuration: --extra-libs=-ldl --prefix=/opt/ffmpeg --mandir=/usr/share/man --enable-avresample --disable-debug --enable-nonfree --enable-gpl --enable-version3 --enable-libopencore-amrnb --enable-libopencore-amrwb --disable-decoder=amrnb --disable-decoder=amrwb --enable-libpulse --enable-libfreetype --enable-gnutls --enable-libx264 --enable-libx265 --enable-libfdk-aac --enable-libvorbis --enable-libmp3lame --enable-libopus --enable-libvpx --enable-libspeex --enable-libass --enable-avisynth --enable-libsoxr --enable-libxvid --enable-libvidstab --enable-libwavpack --enable-nvenc
  
    libavutil      55. 44.100 / 55. 44.100
  
    libavcodec     57. 75.100 / 57. 75.100
  
    libavformat    57. 63.100 / 57. 63.100
  
    libavdevice    57.  2.100 / 57.  2.100
  
    libavfilter     6. 69.100 /  6. 69.100
  
    libavresample   3.  2.  0 /  3.  2.  0
  
    libswscale      4.  3.101 /  4.  3.101
  
    libswresample   2.  4.100 /  2.  4.100
  
    libpostproc    54.  2.100 / 54.  2.100
  
  Input #0, mp3, from '01_FFXV_OST.mp3':
  
    Metadata:
  
      album           : FINAL FANTASY XV Original Soundtrack
  
      artist          : Yoko Shimomura
  
      album_artist    : SQUARE ENIX MUSIC
  
      composer        : Yoko Shimomura
  
      disc            : 1
  
      genre           : Game
  
      title           : Somnus (Instrumental Version)
  
      track           : 01
  
      date            : 2016
  
    Duration: 00:02:29.47, start: 0.023021, bitrate: 306 kb/s
  
      Stream #0:0: Audio: mp3, 48000 Hz, stereo, s16p, 301 kb/s
  
      Metadata:
  
        encoder         : LAME3.98r
  
      Stream #0:1: Video: mjpeg, yuvj444p(pc, bt470bg/unknown/unknown), 500x500 [SAR 100:100 DAR 1:1], 90k tbr, 90k tbn, 90k tbc
  
      Metadata:
  
        comment         : Cover (front)
  
  [ogg @ 0x2ac6e00] Unsupported codec id in stream 0
  
  Could not write header for output file #0 (incorrect codec parameters ?): Invalid argument
  
  Stream mapping:
  
    Stream #0:1 -> #0:0 (copy)
  
    Stream #0:0 -> #0:1 (mp3 (native) -> vorbis (libvorbis))
  
      Last message repeated 1 times

  I have absolutely no clue what to do next. I’ve also tried adding -c:v copy to no avail :

  ffmpeg version git-2017-01-22-f1214ad Copyright (c) 2000-2017 the FFmpeg developers
  
    built with gcc 4.8 (Ubuntu 4.8.4-2ubuntu1~14.04.3)
  
    configuration: --extra-libs=-ldl --prefix=/opt/ffmpeg --mandir=/usr/share/man --enable-avresample --disable-debug --enable-nonfree --enable-gpl --enable-version3 --enable-libopencore-amrnb --enable-libopencore-amrwb --disable-decoder=amrnb --disable-decoder=amrwb --enable-libpulse --enable-libfreetype --enable-gnutls --enable-libx264 --enable-libx265 --enable-libfdk-aac --enable-libvorbis --enable-libmp3lame --enable-libopus --enable-libvpx --enable-libspeex --enable-libass --enable-avisynth --enable-libsoxr --enable-libxvid --enable-libvidstab --enable-libwavpack --enable-nvenc
  
    libavutil      55. 44.100 / 55. 44.100
  
    libavcodec     57. 75.100 / 57. 75.100
  
    libavformat    57. 63.100 / 57. 63.100
  
    libavdevice    57.  2.100 / 57.  2.100
  
    libavfilter     6. 69.100 /  6. 69.100
  
    libavresample   3.  2.  0 /  3.  2.  0
  
    libswscale      4.  3.101 /  4.  3.101
  
    libswresample   2.  4.100 /  2.  4.100
  
    libpostproc    54.  2.100 / 54.  2.100
  
  Input #0, mp3, from '01_FFXV_OST.mp3':
  
    Metadata:
  
      album           : FINAL FANTASY XV Original Soundtrack
  
      artist          : Yoko Shimomura
  
      album_artist    : SQUARE ENIX MUSIC
  
      composer        : Yoko Shimomura
  
      disc            : 1
  
      genre           : Game
  
      title           : Somnus (Instrumental Version)
  
      track           : 01
  
      date            : 2016
  
    Duration: 00:02:29.47, start: 0.023021, bitrate: 306 kb/s
  
      Stream #0:0: Audio: mp3, 48000 Hz, stereo, s16p, 301 kb/s
  
      Metadata:
  
        encoder         : LAME3.98r
  
      Stream #0:1: Video: mjpeg, yuvj444p(pc, bt470bg/unknown/unknown), 500x500 [SAR 100:100 DAR 1:1], 90k tbr, 90k tbn, 90k tbc
  
      Metadata:
  
        comment         : Cover (front)
  
  [ogg @ 0x2b6ce00] Unsupported codec id in stream 0
  
  Could not write header for output file #0 (incorrect codec parameters ?): Invalid argument
  
  Stream mapping:
  
    Stream #0:1 -> #0:0 (copy)
  
    Stream #0:0 -> #0:1 (mp3 (native) -> vorbis (libvorbis))
  
      Last message repeated 1 times

  I get the same results if I change the stream order (by passing -map 0:0 -map 0:1). I’m not sure what to do next...

• MPlayer not playing HTTP video stream for a specific type of content from the same source

  2 août 2017, par Joel

  Implementation overview

  Before I dive into the question, I need to establish the context from the start.

  I am currently implementing a cloud gaming solution utilising the following :

  • Nvidia Capture SDK
  • Nvidia Video Codec SDK
  • FFmpeg
  • MPlayer

  The Nvidia Capture SDK is used to produce a shim layer (via DXGI.dll), intercepting and capturing DirectX frames so that they can be passed to the Nvidia Video Codec SDK to be encoded into an h264 video format. All this is done within DXGI.dll.

  I then pass the encoded video to FFmpeg. FFmpeg acts as an HTTP server that broadcasts the video stream for MPlayer to play.

  Problem

  I am running an Unreal Engine 4 game called "Epic Survival Game Series". The Nvidia Capture SDK’s shim layer kicks off when the game starts, and FFmpeg launches the HTTP server to start streaming. However, when I start MPlayer to receive the stream, MPlayer stops at the following message, and nothing happens after that.

  libavformat version 57.72.101 (internal)
Stream not seekable!
H264-ES file format detected

  The thing is, when I play the same video using ffplay, it works without any issue. This is not the only quirk. When I launch a different Unreal Engine 4 game called "First Person Shooter Template", MPlayer can play that video as well. Also, if I modify the Survival Game to load directly into the game level by skipping the menu, MPlayer is also able to play the video.

  Using FFmpeg to write the video to a file instead of streaming it to a video also works, no matter the game or whether I loaded into the menu or game level.

  This is very strange and I do not have any idea why this is the case. Any ideas ?

  Edit : One strange quirk I forgot to mention is that MPlayer does manage to play the video in very rare occasions - maybe once every 10-20 tries or so.

  Implementation Details

  Additional details of how certain parts are implemented.

  (1) For the Nvidia Capture SDK, I use the provided DXIFRShim example that is provided in the SDK

  (2) for the Nvidia Video Codec SDK, I use the provided NvEncoder example that is provided in the SDK

  (3) The FFmpeg command I use is this :
  ffmpeg -i - -listen 1 -threads 1 -vcodec copy -preset ultrafast -an -tune zerolatency -f h264 http://address:port
  The encoded frames from Nvidia Video Codec SDK is piped to FFmpeg.

  (4) The MPlayer command I use is this :
  mplayer -quiet -vo gl -nosound -benchmark http://address:port

  Things I’ve tried

  I am suspecting MPlayer to be the cause, so I’ve only played around with MPlayer parameters.
  mplayer http://address:port

  mplayer -fps 30 -vo gl -nosound -benchmark http://address:port

  mplayer -fps 30 -screenw 720 -screenh 1280 -vo gl -nosound -benchmark http://address:port

  mplayer -fps 30 -vo directx -nosound -benchmark http://address:port

  mplayer -fps 30 -vo null -nosound -benchmark http://address:port

  None of these worked.