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• Extract image of every frame of a video using react-native-ffmpeg

  1er octobre 2020, par EdG

  I have looked all over the internet to get a way to extract image of everyframe of a video using react-native-ffmpeg. I am making a mobile app and I want to show all per frame images on the video timeline. I want to do this natively on mobile so that I can utilise hardware power of mobile. That is the reason I am looking for react-native-ffmpeg kind of library. Am I in the right direction ? This npmjs.com/package/react-native-ffmpeg is what I am trying to use. I need to know the command to do the job.

  


• Concatenate mp4 video files on iOS using Libavformat

  3 mars 2017, par Felix

  I need to merge (i.e. concatenate) multiple video files (using H.264 codec) in an iOS application. The problem is I can’t use AVFoundation because it can’t handle the video format on iOS (no problem on MacOS). So I tried to use the FFmpeg library, specifically Libavformat for this task. I found C code that looks useful here : http://stackoverflow.com/a/16293046. But i can’t get it to work and don’t understand it completly. The output video file appears to play only black frames. I’m using the precompiled libraries from the FFmpeg CocoaPod.

  I was able to convert a single test video (which has 1GB) using the command line tool on my Mac :

  $ ffmpeg -i input.mp4 -vcodec copy output.mp4
  
  ffmpeg version 3.2.4-tessus Copyright (c) 2000-2017 the FFmpeg developers
  
    built with Apple LLVM version 8.0.0 (clang-800.0.42.1)
  
    configuration: --cc=/usr/bin/clang --prefix=/opt/ffmpeg --extra-version=tessus --enable-avisynth --enable-fontconfig --enable-gpl --enable-libass --enable-libbluray --enable-libfreetype --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopus --enable-libschroedinger --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libzmq --enable-version3 --disable-ffplay --disable-indev=qtkit --disable-indev=x11grab_xcb
  
    libavutil      55. 34.101 / 55. 34.101
  
    libavcodec     57. 64.101 / 57. 64.101
  
    libavformat    57. 56.101 / 57. 56.101
  
    libavdevice    57.  1.100 / 57.  1.100
  
    libavfilter     6. 65.100 /  6. 65.100
  
    libswscale      4.  2.100 /  4.  2.100
  
    libswresample   2.  3.100 /  2.  3.100
  
    libpostproc    54.  1.100 / 54.  1.100
  
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'input.mp4':
  
    Metadata:
  
      major_brand     : mp42
  
      minor_version   : 0
  
      compatible_brands: mp42mp41isomiso2
  
      creation_time   : 2016-09-14T14:35:53.000000Z
  
    Duration: 00:04:32.29, start: 0.000000, bitrate: 30013 kb/s
  
      Stream #0:0(eng): Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 29958 kb/s, 50 fps, 50 tbr, 5k tbn, 100 tbc (default)
  
      Metadata:
  
        creation_time   : 2016-09-14T14:35:53.000000Z
  
        handler_name    : VideoHandler
  
      Stream #0:1(eng): Audio: aac (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default)
  
      Metadata:
  
        creation_time   : 2016-09-14T14:35:53.000000Z
  
        handler_name    : SoundHandler
  
  Output #0, mp4, to 'output.mp4':
  
    Metadata:
  
      major_brand     : mp42
  
      minor_version   : 0
  
      compatible_brands: mp42mp41isomiso2
  
      encoder         : Lavf57.56.101
  
      Stream #0:0(eng): Video: h264 (Main) ([33][0][0][0] / 0x0021), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], q=2-31, 29958 kb/s, 50 fps, 50 tbr, 10k tbn, 5k tbc (default)
  
      Metadata:
  
        creation_time   : 2016-09-14T14:35:53.000000Z
  
        handler_name    : VideoHandler
  
      Stream #0:1(eng): Audio: aac (LC) ([64][0][0][0] / 0x0040), 48000 Hz, stereo, fltp, 128 kb/s (default)
  
      Metadata:
  
        creation_time   : 2016-09-14T14:35:53.000000Z
  
        handler_name    : SoundHandler
  
        encoder         : Lavc57.64.101 aac
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (copy)
  
    Stream #0:1 -> #0:1 (aac (native) -> aac (native))
  
  Press [q] to stop, [?] for help
  
  frame=13577 fps=1280 q=-1.0 Lsize=  997604kB time=00:04:32.28 bitrate=30013.7kbits/s speed=25.7x    
  
  video:993034kB audio:4268kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.030246%
  
  [aac @ 0x7fa849809e00] Qavg: 942.999

  This process is very fast (10 seconds) and I can play the resulting video on iOS using AVFoundation frameworks. If i could do the same for each input video using Libavformat in my iOS app i could solve my problem by merging the videos in a second step using AVAssetExportSession.

  Any help is appreciated.

• Video files are not opening for sample applications in Info Sphere Streams

  10 mars 2017, par Pavan Kumar

  I am new to IBM Info Sphere Streams, I read an article which says IBM Info Sphere streams is capable of doing Image processing. After some research I got to know that, we have to install OpenCV and FFMpeg lybraries with its dependecies. I have installed all of them and tried sample applications. I can run applications which contains Images as input, but when it comes to processing with videos it’s not working. I am unable to use x11viewer operator as well. I am getting the following error while working with sample videos.

  (Streams com.ibm.streamsx.opencv::X11Viewer operator:7889): GLib-GObject-CRITICAL **: g_object_unref: assertion `G_IS_OBJECT (object)' failed
  
  28 Feb 2017 14:00:34.672 [7889] ERROR #splapptrc,J[0],P[0],vid0,spl_pe M[PEImpl.cpp:process:1270]  - CDISR5079E: An exception occurred during the processing of the processing element. The error is: Unable to open camera {0}. 

  I did not install any GPU device drivers here but when I used the following commands I am getting results like below,

  [streamsadmin@streamsqse output]$ lspci | grep VGA
  
  00:0f.0 VGA compatible controller: VMware SVGA II Adapter
  
  
  
  [streamsadmin@streamsqse output]$ find /dev -group video
  
  /dev/fb0
  
  /dev/dri/card0
  
  /dev/dri/renderD128
  
  /dev/dri/controlD64
  
  /dev/agpgart

  and

  glxinfo | grep -i vendor
  
  server glx vendor string: SGI
  
  client glx vendor string: Mesa Project and SGI
  
  OpenGL vendor string: VMware, Inc

  My doubt here is, whether I have installed GPU Drivers properly or do I need to install them again ? Can anyone help me to resolve this issue.

  And I am unable to open those videos by using any player as well.