#include <stdio.h>
#include <time.h>

float inputImage[5][5] = {
	{1,2,3,4,5},
	{6,7,8,9,10},
	{11,12,13,14,15},
	{16,17,18,19,20},
	{21,22,23,24,25}
};

float kernel[3][3] = {
	{1.0f / 16,2.0f / 16,1.0f / 16},
	{2.0f / 16,4.0f / 16,2.0f / 16},
	{1.0f / 16,2.0f / 16,1.0f / 16}
};

void applyGaussianBlur(float src[][5], int w, int h, float dst[][5], float kernel[][3]) {
	for (int i = 1; i < h - 1; ++i) {
		for (int j = 1; j < w - 1; ++j) {
			dst[i][j] =
				src[i - 1][j - 1] * kernel[0][0] + src[i - 1][j] * kernel[0][1] + src[i - 1][j + 1] * kernel[0][2] +
				src[i][j - 1] * kernel[1][0] + src[i][j] * kernel[1][1] + src[i][j + 1] * kernel[1][2] +
				src[i + 1][j - 1] * kernel[2][0] + src[i + 1][j] * kernel[2][1] + src[i + 1][j + 1] * kernel[2][2];
		}
	}
}
int main() {
	float outputImage[5][5] = { 0 };
	clock_t start, end;
	start = clock();
	applyGaussianBlur(inputImage, 5, 5, outputImage, kernel);
	end = clock();
	double timeSpent = (double)(end - start) / CLOCKS_PER_SEC;
	for (int i = 0; i < 5; i++) {
		for (int j = 0; j < 5; j++) {
			printf("%-4.1f ", outputImage[i][j]);
		}
		printf("\n");
	}
	printf("The timeSpent is %1.32f second\n", timeSpent);
}