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MicroBenchmarks/ImageProcessing/Blur/gaussianBlurKernel.c
| /** | |||||
| Gaussian Blur Kernel | |||||
| Pankaj Kukreja | |||||
| github.com/proton0001 | |||||
| Indian Institute of Technology Hyderabad | |||||
| */ | |||||
| #include "blur.h" | |||||
| #include <math.h> // For M_PI and exp | |||||
| void gaussianBlurKernel(int height, int width, int inputImage[height][width], | |||||
| int outputImage[height][width]) { | |||||
| float sigma = 9; | |||||
| float s = 2.0 * sigma * sigma; | |||||
| int offset = (BOX_SIZE - 1) / 2; | |||||
| float sum = 0; | |||||
| float gaussianFilter[BOX_SIZE][BOX_SIZE] = {0}; | |||||
| for (int x = -1 * offset; x <= offset; x++) { | |||||
| for (int y = -1 * offset; y <= offset; y++) { | |||||
| gaussianFilter[x + offset][y + offset] = | |||||
| (exp(-(x * x + y * y) / s)) / (M_PI * s); | |||||
| sum += gaussianFilter[x + offset][y + offset]; | |||||
| } | |||||
| } | |||||
| float sum_in_current_frame = 0; | |||||
| for (int i = offset; i < height - offset; i++) { | |||||
| for (int j = offset; j < width - offset; j++) { | |||||
| /* Computing sum of (elements * corresponding gaussianFilter) in window | |||||
| * centered at i,j */ | |||||
| sum_in_current_frame = 0; | |||||
| for (int k = -1 * offset; k <= offset; k++) { | |||||
| for (int l = -1 * offset; l <= offset; l++) { | |||||
| sum_in_current_frame += (inputImage[i + k][j + l] * | |||||
| gaussianFilter[k + offset][l + offset]); | |||||
| } | |||||
| } | |||||
| outputImage[i][j] = (sum_in_current_frame) / sum; | |||||
| } | |||||
| } | |||||
| } | |||||