不用opencv库c语言卷积实现灰度图像的膨胀和腐蚀，并将膨胀和腐蚀后的图像相减

以下是使用C语言实现的代码示例，其中使用了3x3的矩形结构元素：

#include <stdio.h>
#include <stdlib.h>

#define WIDTH 640
#define HEIGHT 480

// 灰度图像膨胀
void dilate(unsigned char *src, unsigned char *dst, int width, int height)
{
    int i, j, k, l;
    unsigned char max_val;
    unsigned char kernel[3][3] = {
        {1, 1, 1},
        {1, 1, 1},
        {1, 1, 1}
    };  // 3x3的矩形结构元素

    for (i = 1; i < height - 1; i++) {
        for (j = 1; j < width - 1; j++) {
            max_val = 0;
            for (k = -1; k <= 1; k++) {
                for (l = -1; l <= 1; l++) {
                    if (src[(i + k) * width + j + l] * kernel[k + 1][l + 1] > max_val) {
                        max_val = src[(i + k) * width + j + l] * kernel[k + 1][l + 1];
                    }
                }
            }
            dst[i * width + j] = max_val;
        }
    }
}

// 灰度图像腐蚀
void erode(unsigned char *src, unsigned char *dst, int width, int height)
{
    int i, j, k, l;
    unsigned char min_val;
    unsigned char kernel[3][3] = {
        {1, 1, 1},
        {1, 1, 1},
        {1, 1, 1}
    };  // 3x3的矩形结构元素

    for (i = 1; i < height - 1; i++) {
        for (j = 1; j < width - 1; j++) {
            min_val = 255;
            for (k = -1; k <= 1; k++) {
                for (l = -1; l <= 1; l++) {
                    if (src[(i + k) * width + j + l] * kernel[k + 1][l + 1] < min_val) {
                        min_val = src[(i + k) * width + j + l] * kernel[k + 1][l + 1];
                    }
                }
            }
            dst[i * width + j] = min_val;
        }
    }
}

int main()
{
    FILE *fp_in, *fp_out;
    unsigned char *img_in, *img_out1, *img_out2;
    int i, j;

    // 读取灰度图像
    fp_in = fopen("lena_gray.raw", "rb");
    if (!fp_in) {
        printf("Cannot open input file.\n");
        return -1;
    }
    img_in = (unsigned char *)malloc(WIDTH * HEIGHT * sizeof(unsigned char));
    fread(img_in, sizeof(unsigned char), WIDTH * HEIGHT, fp_in);
    fclose(fp_in);

    // 分配输出图像内存
    img_out1 = (unsigned char *)malloc(WIDTH * HEIGHT * sizeof(unsigned char));
    img_out2 = (unsigned char *)malloc(WIDTH * HEIGHT * sizeof(unsigned char));

    // 灰度图像膨胀
    dilate(img_in, img_out1, WIDTH, HEIGHT);

    // 灰度图像腐蚀
    erode(img_in, img_out2, WIDTH, HEIGHT);

    // 相减得到膨胀和腐蚀后的图像差
    for (i = 0; i < HEIGHT; i++) {
        for (j = 0; j < WIDTH; j++) {
            img_out1[i * WIDTH + j] = img_out1[i * WIDTH + j] - img_out2[i * WIDTH + j];
        }
    }

    // 输出图像差
    fp_out = fopen("lena_diff.raw", "wb");
    if (!fp_out) {
        printf("Cannot open output file.\n");
        return -1;
    }
    fwrite(img_out1, sizeof(unsigned char), WIDTH * HEIGHT, fp_out);
    fclose(fp_out);

    // 释放内存
    free(img_in);
    free(img_out1);
    free(img_out2);

    return 0;
}

该程序会读入名为"lena_gray.raw"的灰度图像，然后进行膨胀和腐蚀操作，并将两幅图像相减得到膨胀和腐蚀后的图像差，最后将差图像输出为"lena_diff.raw"文件。