纯c求图形周长

#include"stdio.h" typedef unsigned short WORD; typedef unsigned char BYTE; typedef unsigned int DWORD; typedef signed int LONG; typedef int BOOL; #define FALSE 0 #define TRUE 1 #define bmPixel 256 #define bmSize 512 typedef struct{int x;int y;}Point; LONG bmWidth,bmHeight; DWORD bmOffBits; BYTE bmImg[bmSize][bmSize]; void bmpTest(FILE* fp) { WORD bmpTag; fseek(fp,0L,SEEK_SET); fread(&bmpTag,sizeof(WORD),1,fp); if (0x4D42!=bmpTag) { puts("The format of this file is error!"); return; } } void getWidth(FILE* fp) { fseek(fp,18L,SEEK_SET); fread(&bmWidth,sizeof(LONG),1,fp); } void getHeight(FILE* fp) { fseek(fp,22L,SEEK_SET); fread(&bmHeight,sizeof(LONG),1,fp); } void getOffbit(FILE* fp) { fseek(fp,10L,SEEK_SET); fread(&bmOffBits,sizeof(DWORD),1,fp); } void getPixel(FILE *fp) { int i,j; fseek(fp,bmOffBits,SEEK_SET); for (i = 0; i < bmHeight; i++) for (j = 0; j < bmWidth; j++) { fread(&bmImg[i][j],sizeof(BYTE),1,fp); if (bmImg[i][j] >= 127) bmImg[i][j] = 255; else bmImg[i][j] = 0; } } void calcGirth(BYTE bmImg[bmSize][bmSize],bool mark[bmSize][bmSize]) { int i,j; int ans = 0; //初始化mark全部标记为false for (i = 0; i < bmHeight; i++) for (j = 0; j < bmWidth; j++) mark[i][j] = false; //从下往上计算，如果相邻的不同则标记 for (i = 1; i < bmHeight; i++) for (j = 0; j < bmWidth; j++) if (255==bmImg[i][j]&&0==bmImg[i-1][j]) mark[i][j] = true; else if (255==bmImg[i-1][j]&&0==bmImg[i][j]) mark[i-1][j] = true; //从右往左计算，如果相邻的不同则标记 for (i = 0; i < bmHeight; i++) for (j = 1; j < bmWidth; j++) if (255==bmImg[i][j]&&0==bmImg[i][j-1]) mark[i][j] = true; else if (255==bmImg[i][j-1]&&0==bmImg[i][j]) mark[i][j-1] = true; //计算周长 for (i = 0; i < bmHeight; i++) for (j = 0; j < bmWidth; j++) if (true==mark[i][j]) ans ++; //输出结果 printf("周长 = %d\n",ans); } void copyFile(FILE *srcFile,FILE *desFile) { int i,j,x,y; BYTE tmp; fseek(srcFile,0L,SEEK_SET); //读文件头信息 for (i = 0; i < bmOffBits; i++) { fread(&tmp,sizeof(BYTE),1,srcFile); fwrite(&tmp,sizeof(BYTE),1,desFile); } //读像素信息 fseek(desFile,bmOffBits,SEEK_SET); for (i = 0; i < bmHeight; i++) for (j = 0; j < bmWidth; j++) fwrite(&bmImg[i][j],sizeof(BYTE),1,desFile); } void printPoint(Point point) { int x = point.x; int y = point.y; printf("x = %d y = %d\n",x,y); } BOOL isFind(Point point) { int x = point.x; int y = point.y; if (0==bmImg[y][x]) return TRUE; return FALSE; } int main(void) { FILE *fp,*file; bool mark[bmSize][bmSize]; if (NULL == (fp = fopen("newx2.bmp","rb"))) { puts("Open the file failure!"); return FALSE; } if (NULL == (file = fopen("test.bmp","wb+"))) { puts("Create the file failure!"); return FALSE; } bmpTest(fp); getWidth(fp); getHeight(fp); getOffbit(fp); getPixel(fp); calcGirth(bmImg,mark); copyFile(fp,file); return 0; }