Convert screenshot to OpenCV Mat #36

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1. DarthAffe commented on Jul 15, 2024

   

   DarthAffe

   on Jul 15, 2024

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   hey, this is just based on the docs and not tested. it assumes that emgu.cv is used and opencv has BGRA as internal color format (I couldn't verify that).

   IImage image = default; // get your image here
   Mat material = new Mat(image.Height, image.Width, DepthType.Cv8U, image.ColorFormat.BytesPerPixel);
   image.CopyTo(new Span<byte>((void*)material.DataPointer, image.Width * image.Height * image.ColorFormat.BytesPerPixel));

   or

   RefImage<ColorBGRA> image = default; // get your image here
   Mat material = new Mat(image.Height, image.Width, DepthType.Cv8U, ColorBGRA.ColorFormat.BytesPerPixel);
   image.CopyTo(new Span<ColorBGRA>((void*)material.DataPointer, image.Width * image.Height));

   I'm currently working on abstracting this kind of conversion a bit more to make it easier in the future.
2. rxerox commented on Jul 17, 2024

   

   rxerox

   on Jul 17, 2024

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   Hi, nice and quick answer. Your right, I'am using emgu.cv, and I try your 2nd sample code : it's work fine.

   Again, many thanks ;)
3. glasscake commented on Jun 17, 2025

   

   glasscake

   on Jun 17, 2025

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   hey, this is just based on the docs and not tested. it assumes that emgu.cv is used and opencv has BGRA as internal color format (I couldn't verify that).

   IImage image = default; // get your image here
   Mat material = new Mat(image.Height, image.Width, DepthType.Cv8U, image.ColorFormat.BytesPerPixel);
   image.CopyTo(new Span((void*)material.DataPointer, image.Width * image.Height * image.ColorFormat.BytesPerPixel));
   or

   RefImage image = default; // get your image here
   Mat material = new Mat(image.Height, image.Width, DepthType.Cv8U, ColorBGRA.ColorFormat.BytesPerPixel);
   image.CopyTo(new Span((void*)material.DataPointer, image.Width * image.Height));
   I'm currently working on abstracting this kind of conversion a bit more to make it easier in the future.

   Just for reference I got this code working with OpenCVSharp using the following:

   IImage<ColorBGRA> image = fullscreen.Image;
   Mat material = new Mat(image.Height, image.Width, MatType.CV_8UC4);
   image.CopyTo(new Span<ColorBGRA>((void*)material.DataPointer, image.Width * image.Height));