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• FFmpeg AVFrame to OpenGL texture without YUV to RGB soft conversion

  15 novembre 2018, par zebeurton

  I want to decode an encrypted H264 video file on iOS. I already have ported our decryption algorithm and it is working fine. However, we cannot directly use H264 hardware decoder due to lack of API in SDK.

  So I am trying to find an alternative to decode H264 video. I am trying to use FFmpeg to decode these video even if there are some possible LGPL license issues. I decode H264 video without any problems and I render H264 frames thanks to OpenGL ES texture. But there are some performance issues. I instrumented my code and the bottleneck is the ffmpeg rescaling and YUV to RGB conversion.
  I know that I can use OpenGL ES 2.0 shaders to convert YUV to RGB with GPU acceleration (related post Alternative to ffmpeg for iOS).
  I also know how AVFrame structure is composed : data[0] for Y data, data[1] for U data and data[1] for V data. But I do not understand how can I use line size[x] with data[x] to transmit data to OpenGL texture.

  Does anybody have an example of AVFrame YUV to OpenGL texture ?

  Thanks,
  David

• FFmpeg AVFrame to OpenGL texture without YUV to RGB soft conversion

  23 février 2012, par zebeurton

  I want to decode an encrypted H264 video file on iOS. I already have ported our decryption algorithm and it is working fine. However, we cannot directly use H264 hardware decoder due to lack of API in SDK.

  So I am trying to find an alternative to decode H264 video. I am trying to use FFmpeg to decode these video even if there are some possible LGPL license issues. I decode H264 video without any problems and I render H264 frames thanks to OpenGL ES texture. But there are some performance issues. I instrumented my code and the bottleneck is the ffmpeg rescaling and YUV to RGB conversion.
  I know that I can use OpenGL ES 2.0 shaders to convert YUV to RGB with GPU acceleration (related post Alternative to ffmpeg for iOS).
  I also know how AVFrame structure is composed : data[0] for Y data, data[1] for U data and data[1] for V data. But I do not understand how can I use line size[x] with data[x] to transmit data to OpenGL texture.

  Does anybody have an example of AVFrame YUV to OpenGL texture ?

  Thanks,
  David

• Can't call FFMPEG from CMD after installing chocolatey+ffmpeg on windows docker container

  19 novembre 2022, par Adil Abdul Rahman

  I have a C# code that is dependent on FFMPEG via CMD/powershell. I am trying to run CLI ffmpeg via a C# code in a windows container with sdk:6.0-windowsservercore-ltsc2022. I found this guide(use 12ft.io to bypass paywall) that says to install chocolatey and then install ffmpeg through that like so :

  


  USER ContainerAdministrator
EXPOSE 3389/tcp


RUN powershell.exe \
  Set-ExecutionPolicy Bypass -Scope Process -Force; \
  iwr -Uri 'https://community.chocolatey.org/install.ps1' -UseBasicParsing -OutFile $home/choco_install.ps1; \
  powershell $home/choco_install.ps1; \
  del $home/choco_install.ps1; \
  choco; \
  exit 0;
  
RUN powershell.exe \
  powershell choco install chocolatey-compatibility.extension -y --force; \
  powershell choco install chocolatey-core.extension -y --force; \
  powershell choco install ffmpeg-full -y --force; \
  ffmpeg; \
  exit 0;


  


  ( I am using this guide for C# dockerfile )

  


  And my C# Code :

  


  string command = $"/C ffmpeg -i \"{VideoUri}\" -vn -ac 1 {outputName}.mp3";
Process.Start("cmd.exe", command).WaitForExit();


  


  But I am running into some trouble. My C# code throws this error :

  


  'ffmpeg' is not recognized as an internal or external command, operable program or batch file.

  


  I have tried calling FFMPEG from the dockerfile to test if it has installed but it just returns this :

  


  Step 5/17 : RUN powershell.exe   powershell choco install chocolatey-compatibility.extension -y --force;   powershell choco install chocolatey-core.extension -y --force;   powershell choco install ffmpeg-full -y --force;   ffmpeg;   exit 0;
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