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• C# 16-bit grayscale Bitmap array to video

  7 mars 2024, par Everyone

  I have some scientific data that comes in 16-bit grayscale and is unsigned. I need the wide range of grayscale values and C# already supports the format for Bitmap structure using PixelFormat.Format16bppGrayScale, I am conducting some operations on the data and saving it into a List and I would like to write it into a video file for viewing.

  


  I have looked for many FFMPEG libraries out there and I saw Accord.Video.FFMPEG which does support 32-bit ARGB, when I converted the Bitmaps into ARGB it worked and I could write the video file like this :

  


    int height = images[0].Height;
  int width = images[0].Width;
  var frameRate = 8;

  // create instance of video writer
  var vFWriter = new VideoFileWriter();
  // create new video file
  vFWriter.Open(outputVid + ".mp4", width, height, frameRate, VideoCodec.MPEG4);
  
  
  for(int i=0; i/ MAIN LINE OF FOCUS
  }
  vFWriter.Close();
  vFWriter.Dispose();


  


  As can be seen in the code there is no Stride nor PixelFormat provided to the VideoFileWriter and as per the documentation there are no such properties in the class.

  


  I saw a similar issue people had with C++ and OpenCV2 where the only codec that supports 16-bit grayscale was FFV1. I knew it was a long shot but I tried it :

  


    vFWriter.Open(outputVid + ".mkv", width, height, frameRate, VideoCodec.FFV1);


  


  However, as expected, it yielded no results.

  


  The issue is an exception that is thrown stating the image being written into the VideoFileWriter about the argument being invalid :

  


  


  Unhandled Exception : System.ArgumentException : Parameter is not valid.
  
at System.Drawing.Bitmap.LockBits(Rectangle rect, ImageLockMode flags, PixelFormat format, BitmapData bitmapData)
  
at System.Drawing.Bitmap.LockBits(Rectangle rect, ImageLockMode flags, PixelFormat format)
  
at Accord.Video.FFMPEG.VideoFileWriter.WriteVideoFrame(Bitmap frame, UInt32 frameIndex)

  


  


  This is a common error when the PixelFormat is mismatched (the video writer wants 32-bit ARGB but it is receiving 16-bit grayscale).

  


  I confirmed this was the case by updating the write code to this :

  


    for(int i=0; icode>

  


  And now the exception thrown says :

  


  


  Unhandled Exception : System.ArgumentException : The provided bitmap must be 24 or 32 bpp color image or 8 bpp grayscale image.

  


  


  I cannot afford to convert to 32-bit ARGB because that only allows 256 of grayscale and I need the whole 16-bit range.

  


  I looked at other libraries that handle FFMPEG with C# and found Xabe.FFMPEG but it does not support constructing a video from images.

  


  Are there libraries other than Accord.Video.FFMPEG which are capable of constructing a video from 16-bit grayscale frames ?

  


• Revision 29188 : 2 options de plus pour personnaliser la page d’activation de la mutu : * ...

  15 juin 2009, par real3t@… — Log

  2 options de plus pour personnaliser la page d’activation de la mutu :
  * ’branding’ : texte libre en HTML
  * ’branding_logo’ => logo (sous forme de HTML)

• Revision 31960 : Sur la page de création de chaque menu, un lien direct pour voir ce qu’il ...

  7 octobre 2009, par rastapopoulos@… — Log

  Sur la page de création de chaque menu, un lien direct pour voir ce qu’il donne une fois généré.