Bmp图像的哈夫曼编码代码

1、Bmp图像的哈夫曼编码代码#include <stdio.h>#include <stdlib.h>#include <string.h>#include <math.h>#include <windows.h>#include <ctype.h> #include <malloc.h>typedef structunsigned int weight;unsigned int parent,lchild,rchild;HTNode, *huffmantree;/ 动态分配数组存储赫夫曼树typedef cha

2、r *huffmancode;/ 动态分配数组存储赫夫曼编码表int power(int i)int j,result=1;for(j=0;j<i;j+)result*=2;return result;void write_ temp,FILE *fp2)int i;unsigned char result=0;for(i=8;i>0;i-)if(temp8-i!='0')result+=power(i-1);strcpy(temp,temp+8);void select(huffmantree HT, unsigned int i, unsigned int *s

3、1, unsigned int *s2)/ s1为最小的两个值中序号小的那个unsigned int j,temp;for(j=1;j<=i;j+)if(HTj.parent=0)*s2=j;break;for(;j<=i;j+)if(HTj.parent=0 && j!=*s2)*s1=j;break;for(j=1;j<=i;j+)if(HTj.parent=0 && HTj.weight < HT*s1.weight && *s2!=j)*s1=j;for(j=1;j<=i;j+)if(HTj.parent=0

4、 && HTj.weight < HT*s2.weight && *s1!=j)*s2=j;if(*s1>*s2)temp=*s1;*s1=*s2;*s2=temp;void huffmancoding(huffmantree &HT, huffmancode &HC,unsigned long int *w, unsigned int n)/ w存放n个字符的权值(均>0),构造赫夫曼树HT,并求出n个字符的赫夫曼编码HCunsigned int s1,s2,start,c,f,i,m;/ 0号单元未用huffmantree

5、p;char *cd;if (n<=1) return;m=2*n-1;HT=(huffmantree)malloc(m+1)*sizeof(HTNode);/malloc 向系统申请分配指定size个字节的内存空间。for(p=HT+1,i=1; i<=n; +i,+p,+w)p->weight=*w;p->parent=0;p->lchild=0;p->rchild=0;for(; i<=m; +i,+p)p->weight=0;p->parent=0;p->lchild=0;p->rchild=0;for(i=n+1; i

6、<=m; +i)/ 建赫夫曼树 / 在HT1i-1中选择parent为0且weight最小的两个结点,其序号分别为s1和s2select(HT,i-1,&s1,&s2);HTs1.parent=i; HTs2.parent=i;HTi.lchild=s1; HTi.rchild=s2;HTi.weight=HTs1.weight+HTs2.weight; / 从叶子到根逆向求每个字符的赫夫曼编码HC=(huffmancode)malloc(n+1)*sizeof(char *);/ 分配n个字符编码的头指针向量(0不用cd=(char *)malloc(n*sizeof(

7、char); cdn-1='0'/ 编码结束符for(i=1; i<=n; +i)/ 逐个字符求赫夫曼编码start=n-1;/ 编码结束符位置for(c=i,f=HTi.parent; f!=0; c=f,f=HTf.parent)/ 从叶子到根逆向求编码if(HTf.lchild=c)cd-start='0'else cd-start='1'HCi=(char *)malloc(n-start)*sizeof(char); / 为第i个字符编码分配空间strcpy(HCi,&cdstart);/ 从cd复制编码(串)到HCfre

8、e(cd);/ 释放工作空间void main()char w256="0"char temp40="0"unsigned char len;unsigned long int count256=0,weight256=0,n=0,i=0;unsigned int q=0;unsigned long int *p;char 260="0",260="0",houzui8="0"char *point;char colorplat1024;FILE *fp,*fp2;huffmantree HT;

9、huffmancode HC;BITMAP bf;/BMP文件头结构体 BITMAPINFOHEADER bi;/BMP信息头结构体 /打开文件 printf("input the ：");gets();/从stdin流中读取字符串，直至接受到换行符或EOF时停止，并将读取的结果存放在str指针所指向的字符数组中。strcpy();for(point=(); *point!='.' point-);/文件名修改strcpy(houzui,point);strcpy(point,".shq");if(fp=fopen(,"rb&q

10、uot;)=NULL)/fopen函数用来打开一个文件printf("errorn");exit(1);/读取信息头、文件头 fread( &bf,sizeof(BITMAP), 1, fp ); /把指针fp所指向的文件的头信息写入bf（地址） fread( &bi,sizeof(BITMAPINFOHEADER), 1, fp ); if(bf.bfType != 0x4d42) /校验图片类型printf("文件非bmp格式 n");exit(1);if(bi.biBitCount<24)int tm;(int)tm=pow(

11、2.,bi.biBitCount);fread(colorplat,4*tm,1,fp);while(fread(&q,1,1,fp)countq+;fclose(fp);for(p=count;i<256;p+,i+)weightn+=*p;huffmancoding(HT,HC,weight,n);for(i=0,n=1;i<256;i+)if(counti!=0)printf("%d: ",i);printf("%sn",HCn+);if(fp=fopen(,"rb")=NULL) /只读打开或建立一个二进制

12、文件，只允许读数据printf("errorn");exit(1);if(fp2=fopen(,"wb")=NULL) /只写打开或建立一个二进制文件，只允许写数据printf("errorn");exit(1);fwrite( &bf,sizeof(BITMAP), 1 ,fp2 );fwrite( &bi,sizeof(BITMAPINFOHEADER), 1, fp2 );if(bi.biBitCount<24)/调用套色板fwrite(colorplat,4*(int)pow(2.,bi.biBitCount),1,fp2);fwrite(houzui,8,1,fp2);for(i=1;i<=256;i+)len=strlen(HCi);fwrite(&len,1,1,fp2);fwrite(HCi,len,1,fp2);fseek(fp,54L,0);/跳过文件头while(fread(&q,1,1,fp)strca