public static void convolve(Kernel2D_F64 kernel, GrayF64 input, GrayF64 output) { final double[] dataSrc = input.data; final double[] dataDst = output.data; final double[] dataKer = kernel.data; final int kernelWidth = kernel.getWidth(); final int offsetL = kernel.getOffset(); final int offsetR = kernelWidth - offsetL - 1; final int width = input.getWidth(); final int height = input.getHeight(); // convolve across the left and right borders for (int y = 0; y < height; y++) { int minI = y >= offsetL ? -offsetL : -y; int maxI = y < height - offsetR ? offsetR : height - y - 1; int indexDst = output.startIndex + y * output.stride; for (int x = 0; x < offsetL; x++) { double total = 0; double weight = 0; for (int i = minI; i <= maxI; i++) { int indexSrc = input.startIndex + (y + i) * input.stride + x; int indexKer = (i + offsetL) * kernelWidth; for (int j = -x; j <= offsetR; j++) { double w = dataKer[indexKer + j + offsetL]; weight += w; total += (dataSrc[indexSrc + j]) * w; } } dataDst[indexDst++] = (total / weight); } indexDst = output.startIndex + y * output.stride + width - offsetR; for (int x = width - offsetR; x < width; x++) { int maxJ = width - x - 1; double total = 0; double weight = 0; for (int i = minI; i <= maxI; i++) { int indexSrc = input.startIndex + (y + i) * input.stride + x; int indexKer = (i + offsetL) * kernelWidth; for (int j = -offsetL; j <= maxJ; j++) { double w = dataKer[indexKer + j + offsetL]; weight += w; total += (dataSrc[indexSrc + j]) * w; } } dataDst[indexDst++] = (total / weight); } } // convolve across the top border while avoiding convolving the corners again for (int y = 0; y < offsetL; y++) { int indexDst = output.startIndex + y * output.stride + offsetL; for (int x = offsetL; x < width - offsetR; x++) { double total = 0; double weight = 0; for (int i = -y; i <= offsetR; i++) { int indexSrc = input.startIndex + (y + i) * input.stride + x; int indexKer = (i + offsetL) * kernelWidth; for (int j = -offsetL; j <= offsetR; j++) { double w = dataKer[indexKer + j + offsetL]; weight += w; total += (dataSrc[indexSrc + j]) * w; } } dataDst[indexDst++] = (total / weight); } } // convolve across the bottom border for (int y = height - offsetR; y < height; y++) { int maxI = height - y - 1; int indexDst = output.startIndex + y * output.stride + offsetL; for (int x = offsetL; x < width - offsetR; x++) { double total = 0; double weight = 0; for (int i = -offsetL; i <= maxI; i++) { int indexSrc = input.startIndex + (y + i) * input.stride + x; int indexKer = (i + offsetL) * kernelWidth; for (int j = -offsetL; j <= offsetR; j++) { double w = dataKer[indexKer + j + offsetL]; weight += w; total += (dataSrc[indexSrc + j]) * w; } } dataDst[indexDst++] = (total / weight); } } }