private static Image <Complex, TDepth> prepareImage <TDepth>(Image <Gray, TDepth> image, int biggestKernelWidth, int biggestKernelHeight,
ConvolutionBorder options,
out int fillX, out int fillY)
where TDepth : struct
{
int FFTNumOfCols = (int)System.Math.Pow(2.0, System.Math.Ceiling(System.Math.Log(biggestKernelWidth + image.Width, 2.0)));
int FFTNumOfRows = (int)System.Math.Pow(2.0, System.Math.Ceiling(System.Math.Log(biggestKernelHeight + image.Height, 2.0)));
fillX = System.Math.Min(image.Width, biggestKernelWidth / 2);
fillY = System.Math.Min(image.Height, biggestKernelHeight / 2);
Rectangle centerRegion = new Rectangle(fillX, fillY, image.Width, image.Height);
Image <Gray, TDepth> paddedImage = new Image <Gray, TDepth>(FFTNumOfCols, FFTNumOfRows);
//center
paddedImage.GetSubRect(centerRegion).SetValue(image);
if (options == ConvolutionBorder.BorderMirror)
{
ParallelConvolution.MirrorBorders(image, paddedImage, fillX, fillY);
}
Image <Complex, TDepth> paddedImageCmplx = new Image <Complex, TDepth>(new Image <Gray, TDepth>[] { paddedImage, paddedImage.CopyBlank() });
paddedImageCmplx.FFT(FourierTransform.Direction.Forward, true);
return(paddedImageCmplx);
}
private static IImage prepareSourceImage(IImage src, Size kernelSize, ConvolutionBorder options, out Rectangle validRegion)
{
var preparedSrc = Image.Create(src.ColorInfo, src.Width + kernelSize.Width, src.Height + kernelSize.Height);
Rectangle centerRegion = new Rectangle(kernelSize.Width / 2, kernelSize.Height / 2, src.Width, src.Height);
preparedSrc.GetSubRect(centerRegion).SetValue(src);
if (options == ConvolutionBorder.BorderMirror)
{
ParallelConvolution.MirrorBorders(src, preparedSrc, centerRegion.X, centerRegion.Y);
}
validRegion = centerRegion;
return(preparedSrc);
}
private static IEnumerable <Image <Gray, TDepth> > ConvolveSeparated <TDepth>(Image <Gray, TDepth> image, Image <Gray, TDepth>[] kernels, ConvolutionBorder options)
where TDepth : struct /*float and double */
{
int biggestKernelWidth, biggestKernelHeight;
ParallelConvolution.GetTheBiggestSize(kernels, out biggestKernelWidth, out biggestKernelHeight);
int fillX, fillY;
var paddedIm = prepareImage(image, biggestKernelWidth, biggestKernelHeight, options, out fillX, out fillY);
foreach (var kernel in kernels)
{
var preparedKernel = prepareKernel(kernel, paddedIm.Size);
var convolvedIm = paddedIm.Mul(preparedKernel, null);
yield return(getConvolutionResult(convolvedIm, fillX, fillY, image.Size, true));
}
}
private static Image <Gray, TDepth> convolve <TDepth>(Image <Gray, TDepth> image, Image <Gray, TDepth>[] kernels, ConvolutionBorder options)
where TDepth : struct
{
int biggestKernelWidth, biggestKernelHeight;
ParallelConvolution.GetTheBiggestSize(kernels, out biggestKernelWidth, out biggestKernelHeight);
int fillX, fillY;
var paddedIm = prepareImage(image, biggestKernelWidth, biggestKernelHeight, options, out fillX, out fillY);
Image <Complex, TDepth> convolvedIm = paddedIm;
foreach (var kernel in kernels)
{
var preparedKernel = prepareKernel(kernel, convolvedIm.Size);
convolvedIm = convolvedIm.Mul(preparedKernel, null);
}
return(getConvolutionResult(convolvedIm, fillX, fillY, image.Size, true));
}