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c#gaussianconvolutioniplimage

How to handle ImgData in C#?

I'm trying to implement an retinex filter following the one posted here. At the beginning he defines:

#define pc(image, x, y, c) image->imageData[(image->widthStep * y) + (image->nChannels * x) + c]

and when doing the gaussian convolution he is using it as:

v1 += kernel[k] * (unsigned char)pc(temp, i, source, 0);

and later:

pc(img, i, j, 0) = (char)int2smallint(v1);

I'm not able to translate this to C#, neither do I understand what he's doing exactly. There are no unsigned chars in C# and also the way he access the image data is completely different. So, what is the best way to implement this in C#?

Solution

  • ok i solved it. This:

    v1 += kernel[k] * (unsigned char)pc(temp, i, source, 0);

    is translated to:

    IntPtr ptr = img.ImageData;
v1 += kernel[k] * Marshal.ReadByte(ptr, (i * img.WidthStep) + (source * img.NChannels) + 0);

    Marshal is the answer :)