纯高斯模糊源码

#define _CRT_SECURE_NO_WARNINGS

#include <stdlib.h>#include <stdint.h>#include <math.h>#include <conio.h>#include <malloc.h>#include "time.h"  #define SQRT_2PI 2.506628274631#pragma pack(push,2)typedef struct{uint16_t bfType;uint32_t bfileSize;uint32_t bfReserved;uint32_t bOffBits;uint32_t biSize;uint32_t biWidth;uint32_t biHeight;uint16_t biPlanes;uint16_t biBitCount;uint32_t biCompression;uint32_t biSizeImage;uint32_t biXPelsPerMeter;uint32_t biYPelsPerMeter;uint32_t biClrUsed;uint32_t biClrImportant;} bmp_header_t;#pragma pack(pop)typedef struct{bmp_header_t header;char *data;} bmp_t;int win_size(double);double Gauss(double, double);double *GaussAlgorithm(int, double);void bmp_free(bmp_t *);bmp_t *bmp_open(FILE *);int bmp_write(bmp_t*, FILE*);bmp_t *GaussBlur(bmp_t*, double);int main(int argc, char** argv){char *InputName, *OutputName;FILE *InputFile, *OutputFile;bmp_t *bmp = NULL, *blur = NULL;clock_t start, finish;     double duration; InputName = "input.bmp"; OutputName = "output.bmp";if (0 != fopen_s(&InputFile, InputName, "rb")){printf("File not found\n");_getch();return 1;}bmp = bmp_open(InputFile);fclose(InputFile);OutputFile = fopen(OutputName, "wb");if (OutputFile == NULL) {fprintf(stderr, "Can't open %s\n", OutputName);return EXIT_FAILURE;}start = clock();  blur = GaussBlur(bmp, 4.0);finish = clock();          duration = (double)(finish - start) / CLOCKS_PER_SEC;          printf( "%f seconds\n", duration );      bmp_write(blur, OutputFile);  fclose(OutputFile);bmp_free(bmp);free(blur);getchar();return 0;}bmp_t *GaussBlur(bmp_t *src, double sigma) {introw, col, col_r, col_g, col_b, winsize, halfsize, k, count, rows, count1, count2, count3;int width, height;double  row_g, row_b, row_r, col_all;unsigned char  r_r, r_b, r_g, c_all;char *tmp;double *algorithm;count=0;width = 3*src->header.biWidth; height = src->header.biHeight;if ((width % 4) != 0) width += (4 - (width % 4)); bmp_t *blur;blur = (bmp_t*)malloc(sizeof(bmp_t));blur->header = src->header;blur->header.biWidth = src->header.biWidth;blur->header.biHeight = src->header.biHeight;blur->header.biSizeImage = width * blur->header.biHeight;blur->data = (char*)malloc(blur->header.biSizeImage);winsize = win_size(sigma);algorithm = GaussAlgorithm(winsize, sigma); winsize *= 3; halfsize = winsize / 2;tmp = (char*)calloc(width * height, sizeof(char)); for (row = 0; row < height; row++){col_r = 0;col_g = 1;col_b = 2;for (rows = 0; rows < width; rows += 3){row_r = row_g = row_b = 0.0;count1 = count2 = count3 = 0;for (k = 1; k < winsize; k += 3){if ((k + col_r - halfsize >= 0) && (k + col_r - halfsize < width)){r_r = *(src->data + row * width + col_r + k - halfsize);row_r += (int)(r_r)* algorithm[count1];count1++;}if ((k + col_g - halfsize >= 0) && (k + col_g - halfsize < width)){r_g = *(src->data + row * width + col_g + k - halfsize);row_g += (int)(r_g)* algorithm[count2];count2++;}if ((k + col_b - halfsize >= 0) && (k + col_b - halfsize < width)){r_b = *(src->data + row * width + col_b + k - halfsize);row_b += (int)(r_b)* algorithm[count3];count3++;}}*(tmp + row * width + col_r) = (unsigned char)(ceil(row_r));*(tmp + row * width + col_g) = (unsigned char)(ceil(row_g));*(tmp + row * width + col_b) = (unsigned char)(ceil(row_b));col_r += 3;col_g += 3;col_b += 3;}}winsize /= 3;halfsize = winsize / 2;for (col = 0; col < width; col++)for (row = 0; row < height; row++){col_all = 0.0;for (k = 0; k < winsize; k++)if ((k + row - halfsize >= 0) && (k + row - halfsize < height)){c_all = *(tmp + (row + k - halfsize) * width + col);col_all += ((int)c_all) * algorithm[k];}*(blur->data + row * width + col) = (unsigned char)(ceil(col_all));}free(tmp);free(algorithm);return blur;}double* GaussAlgorithm(int win_size, double sigma){int wincenter, x;double *kern, sum = 0.0;wincenter = win_size / 2;kern = (double*)calloc(win_size, sizeof(double));for (x = 0; x < wincenter + 1; x++){kern[wincenter - x] = kern[wincenter + x] = Gauss(sigma, x);sum += kern[wincenter - x] + ((x != 0) ? kern[wincenter + x] : 0.0);}for (x = 0; x < win_size; x++)kern[x] /= sum;return kern;}double Gauss(double sigma, double x){return exp(-(x * x) / (2.0 * sigma * sigma)) / (sigma * SQRT_2PI);}int win_size(double sigma){return (1 + (((int)ceil(3 * sigma)) * 2)); }bmp_t *bmp_open(FILE *f) {bmp_t *bmp;bmp = (bmp_t *)malloc(sizeof(bmp_t));bmp->data = NULL;if (fread(&(bmp->header), sizeof(bmp_header_t), 1, f)) {bmp->data = (char*)malloc(bmp->header.biSizeImage);if (fread(bmp->data, bmp->header.biSizeImage, 1, f))return bmp;}fprintf(stderr, "Error reading file");bmp_free(bmp);return NULL;}int bmp_write(bmp_t *bmp, FILE *out) {return fwrite(&(bmp->header), sizeof(bmp_header_t), 1, out)&& fwrite(bmp->data, bmp->header.biSizeImage, 1, out);}void bmp_free(bmp_t *bmp){if (bmp == NULL) return;if (bmp->data != NULL) free(bmp->data);free(bmp);}

电脑配置(开发环境VS2010)：

原图像：

模糊后：

图像大小（5000*3000bmp图像），模糊半径sigma=4.0(≈12*12的模糊核)，从处理效果上看，模糊并没有自己想想的严重，主要是图片比较大，细节分布距离比较大的缘故。所以大图像使用大的模糊核，小图像使用小的模糊核是有道理的。

处理时间：

图像大小（1024*681）模糊半径同上

图像大小（1024*685）模糊半径同上

我一开始练习，开始慢慢练习，ㄟ(⊙ω⊙ㄟ)哈！！

可见同样的模糊半径处理较小的图片，模糊的效果会更加的明显！