Bmp图像的哈夫曼编码代码.doc

Bmp图像的哈夫曼编码代码#include #include #include #include #include #include #include typedef structunsigned int weight;unsigned int parent,lchild,rchild;HTNode, *huffmantree;/ 动态分配数组存储赫夫曼树typedef char *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;j0;i-)if(temp8-i!=0)result+=power(i-1);strcpy(temp,temp+8);void select(huffmantree HT, unsigned int i, unsigned int *s1, 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 & HTj.weight *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 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; iweight=*w;p-parent=0;p-lchild=0;p-rchild=0;for(; iweight=0;p-parent=0;p-lchild=0;p-rchild=0;for(i=n+1; i=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(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HCfree(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 filename260=0,filename2260=0,houzui8=0;char *point;char colorplat1024;FILE *fp,*fp2;huffmantree HT;huffmancode HC;BITMAPFILEHEADER bf;/BMP文件头结构体 BITMAPINFOHEADER bi;/BMP信息头结构体 /打开文件 printf(input the file name ：);gets(filename);/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(filename2,filename);for(point=filename2+strlen(filename2); *point!=.; point-);/文件名修改strcpy(houzui,point);strcpy(point,.shq);if(fp=fopen(filename,rb)=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(BITMAPFILEHEADER), 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.biBitCount24)int tm;(int)tm=pow(2.,bi.biBitCount);fread(colorplat,4*tm,1,fp);while(fread(&q,1,1,fp)countq+;fclose(fp);for(p=count;i256;p+,i+)weightn+=*p;huffmancoding(HT,HC,weight,n);for(i=0,n=1;i256;i+)if(counti!=0)printf(%d: ,i);printf(%sn,HCn+);if(fp=fopen(filename,rb)=NULL) /只读打开或建立一个二进制文件，只允许读数据printf(errorn);exit(1);if(fp2=fopen(filename2,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(BITMAPFILEHEADER), 1 ,fp2 );fwrite( &bi,sizeof(BITMAPINFOHEADER), 1, fp2 );if(bi.biBitCount24)/调用套色板fwrite(colorplat,4*(int)pow(2.,bi.biBitCount),1,fp2);fwrite(h