/* * ===================================================================================== * * Filename: haffman.c * * Description: huffman coder decoder * * Version: 1.0 * Created: * Revision: none * Compiler: gcc * * * ===================================================================================== */ #include <unistd.h> #include <assert.h> #include <stdio.h> #include <stdlib.h> #include <stdio.h> #include <math.h> #include <stdlib.h> #include <string.h> #define N 256 #define Maxsize 80 #define SOME 1 #define Empty 0 #define FULL -1 typedef unsigned long int WeightType; typedef unsigned char MyType; typedef struct //哈夫曼树 { MyType ch; //存字符 WeightType weight; /* 用来存放各个结点的权值 */ int parent, LChild, RChild; /*指向双亲、孩子结点的指针 */ } HTNode; typedef struct //队列 { int tag; int front; int rear; MyType length; char elem[Maxsize]; } SeqQueue; void writeFile(); void printHFM(HTNode * ht, int n); void code(char **hc, int n, unsigned char *ch); int InitQueue(SeqQueue * Q) { if (!Q) return 1; Q->tag = Empty; Q->front = Q->rear = 0; Q->length = 0; return 0; } int In_seqQueue(SeqQueue * Q, char x) { if (Q->front == Q->rear && Q->tag == SOME) return FULL; //full Q->elem[Q->rear] = x; // printf("in = %c",x); Q->rear = (Q->rear + 1) % Maxsize; Q->length++; Q->tag = SOME; return SOME; } int Out_Queue(SeqQueue * Q, char *x) { if (Q->tag == Empty) return Empty; *x = Q->elem[Q->front]; Q->length--; Q->front = (Q->front + 1) % Maxsize; if (Q->front == Q->rear) Q->tag = Empty; return SOME; } /* ------------------以上是队列的操作------------------------- */ void SelectMinTree(HTNode * ht, int n, int *k) { int i, temp; WeightType min; // printf(" Selecting……n= %d",n); for (i = 0; i <= n; i++) { if (0 == ht[i].parent) { min = ht[i].weight; //init min temp = i; break; } } for (i++; i <= n; i++) { if (0 == ht[i].parent && ht[i].weight < min) { min = ht[i].weight; temp = i; } } *k = temp; } // 对哈夫曼树排序，并统计叶子数量 int SortTree(HTNode * ht) { short i, j; HTNode tmp; for (i = N - 1; i >= 0; i--) { for (j = 0; j < i; j++) if (ht[j].weight < ht[j + 1].weight) { tmp = ht[j]; ht[j] = ht[j + 1]; ht[j + 1] = tmp; } } for (i = 0; i < N; i++) if (0 == ht[i].weight) return i; return i; //返回叶子个数 } //求哈夫曼0-1字符编码表 char **CrtHuffmanCode(HTNode * ht, short LeafNum) /*从叶子结点到根，逆向求每个叶子结点对应的哈夫曼编码*/ { char *cd, **hc; //容器 int i, start, p, last; hc = (char **)malloc((LeafNum) * sizeof(char *)); /*分配n个编码的头指针 */ if (1 == LeafNum) //只有一个叶子节点时 { hc[0] = (char *)malloc((LeafNum + 1) * sizeof(char)); strcpy(hc[0], "0"); return hc; } cd = (char *)malloc((LeafNum + 1) * sizeof(char)); /*分配求当前编码的工作空间 */ cd[LeafNum] = ' '; /*从右向左逐位存放编码，首先存放编码结束符 */ for (i = 0; i < LeafNum; i++) { /*求n个叶子结点对应的哈夫曼编码 */ start = LeafNum; /*初始化编码起始指针 */ last = i; for (p = ht[i].parent; p != 0; p = ht[p].parent) { /*从叶子到根结点求编码 */ if (ht[p].LChild == last) cd[--start] = '0'; /*左分支标0 */ else cd[--start] = '1'; /*右分支标1 */ last = p; } hc[i] = (char *)malloc((LeafNum - start) * sizeof(char)); /*为第i个编码分配空间 */ strcpy(hc[i], &cd[start]); // printf("%3d号 %3c 码长:%2d;编码:%s ", ht[i].ch, ht[i].ch, LeafNum - start, &cd[start]); } //getchar(); free(cd); // Printcode(hc,n); return hc; } HTNode *CreatHFM(FILE * fp, short *n, WeightType * FileLength) { HTNode *ht = NULL; int i, m, s1, s2; MyType ch; ht = (HTNode *)malloc(2 * N * sizeof(HTNode)); if (!ht) exit(1); for (i = 0; i < N; i++) { ht[i].weight = 0; ht[i].ch = (MyType)i; /*1-n号ch 为字符，初始化 */ } for (*FileLength = 0; !feof(fp); ++(*FileLength)) { ch = fgetc(fp); //fread(&ch,1,1,fp); ht[ch].weight++; //printf("ht[%c].weight= %ld ",0,ht[0].weight); } --(*FileLength); //去掉文件结束后的长度 *n = SortTree(ht); m = *n * 2 - 1; //free(&ht[m+1]); //printf("叶子个数= %d ",*n);//getchar(); if (1 == *n) { ht[0].parent = 1; return ht; } else if (0 > *n) return NULL; for (i = m - 1; i >= 0; i--) { ht[i].LChild = 0; ht[i].parent = 0; ht[i].RChild = 0; } /* ------------初始化完毕！对应算法步骤1--------- */ for (i = *n; i < m; i++) //创建非叶子结点,建哈夫曼树 { //在ht[0]~ht[i-1]的范围内选择两个parent为0且weight最小的结点，其序号分别赋值给s1、s2返回 SelectMinTree(ht, i - 1, &s1); ht[s1].parent = i; ht[i].LChild = s1; SelectMinTree(ht, i - 1, &s2); ht[s2].parent = i; ht[i].RChild = s2; ht[i].weight = ht[s1].weight + ht[s2].weight; } /*哈夫曼树建立完毕 */// puts(" over^_^"); return ht; } //从队列里取8个字符（0、1），转换成一个字节 MyType GetBits(SeqQueue * Q) { MyType i, bits = 0; char x; for (i = 0; i < 8; i++) { if (Out_Queue(Q, &x) != Empty) { //printf("%c",x); if ('0' == x) bits = bits << 1; else bits = (bits << 1) | 1; } else break; } //printf(" bits=%d ",bits);puts(""); return bits; } //求最长（最短）编码长度 void MaxMinLength(FILE * File, HTNode * ht, char **hc, short NLeaf, MyType * Max, MyType * Min) { int i; MyType length; *Max = *Min = strlen(hc[0]); for (i = 0; i < NLeaf; i++) { length = strlen(hc[i]); fwrite(&ht[i].ch, sizeof(MyType), 1, File); //字符和对应的 fwrite(&length, sizeof(MyType), 1, File); //编码长度写进文件 if (length > *Max) *Max = length; if (length < *Min) *Min = length; } } //把出现过的字符编码表经过压缩写进文件 short CodeToFile(FILE * fp, char **hc, short n, SeqQueue * Q, MyType * length) { int i; char *p; MyType j, bits; short count = 0; for (i = 0; i < n; i++) // 将n个叶子压缩并写入文件 { for (p = hc[i]; ' ' != *p; p++) In_seqQueue(Q, *p); while (Q->length > 8) { // puts("出队"); bits = GetBits(Q); //出队8个元素 fputc(bits, fp); //fwrite(&bits,sizeof(char),1,fp); //printf("压字符 %c ",bits); count++; } } // printf("码字最后剩: %d ",Q->length); *length = Q->length; i = 8 - *length; bits = GetBits(Q); //取8个如果队不空 for (j = 0; j < i; j++) bits = bits << 1; //printf("压 字符 %c ",bits); fputc(bits, fp); //fwrite(&bits,sizeof(char),1,fp); count++; //printf(" 指 针 在%d ",ftell(fp)); InitQueue(Q); return count; } //压缩 void Compress() { char desFile[80], rename[80]; MyType maxLen, minLen, ch, bits, n, finalLength; int i; short LeafNum, codeNum; WeightType count = 0, Length = 0, FileLength; FILE *fp, *compressFile; SeqQueue *Q; HTNode *ht = NULL; char **hc = NULL, **Map = NULL, *p; printf("filename to be compressed:"); scanf("%s", desFile); //getchar();//fflush(stdin);//清空输入缓冲区域 printf("filename after compressed:"); scanf("%s", rename); if (' ' == rename[0]) { printf("输入不能为空，请重新输入:"); scanf("%s", rename); } compressFile = fopen(rename, "wb"); fp = fopen(desFile, "rb"); //原文件 if (!fp || !compressFile) { puts("Cannot open file."); return; } ht = CreatHFM(fp, &LeafNum, &FileLength); //创建哈夫曼树,统计叶子个数和原文件长度 if (!FileLength) { // printf("文件为空，无须压缩..."); fclose(fp); fclose(compressFile); free(ht); return; } Q = (SeqQueue *)malloc(sizeof(SeqQueue)); InitQueue(Q); //SEEK_SET:文件开头 SEEK_CUR:当前位置 SEEK_END:文件结尾 hc = CrtHuffmanCode(ht, LeafNum); //取得哈夫曼0、1编码,hc的长度为LeafNum //Map为了取编码好定位，再建立全部(256个)// Map = (char **)malloc(N * sizeof(char *)); //字符编码表 if (!Map) { puts("申请空间失败"); return; } for (i = 0; i < N; i++) //初始化 Map[i] = NULL; for (i = 0; i < LeafNum; i++) // 定位，编码指针数组Map[256] Map[(int)(ht[i].ch)] = hc[i]; fseek(compressFile, sizeof(WeightType) + sizeof(short) + 6 * sizeof(MyType), SEEK_SET); //先占个位置 //先占个位置,等下填压缩叶子编码剩几个和最长编码长//getchar(); MaxMinLength(compressFile, ht, hc, LeafNum, &maxLen, &minLen); //获得最长码串长度,顺便填写字符对应编码长 // for(i = 0;i < LeafNum;i++) // if(ht[i].ch == (MyType)1) // printf("char %c %s ",ht[i].ch,hc[i]); free(ht); //getchar();printf("最长码串长度: %d ",MaxCode);printf("ftell = %d ",ftell(compressFile)); codeNum = CodeToFile(compressFile, hc, LeafNum, Q, &finalLength); //把字符转成其二进制编码写入文件,返回压成多少个 rewind(compressFile); //使文件指针移到开始printf("ftelll = %d ",ftell(compressFile)); fseek(compressFile, sizeof(WeightType) + sizeof(MyType), SEEK_SET); fwrite(&LeafNum, sizeof(short), 1, compressFile); //写入叶子个数 fwrite(&maxLen, sizeof(MyType), 1, compressFile); //最长码串长度 fwrite(&minLen, sizeof(MyType), 1, compressFile); //最短码串长度 //printf("MaxLen %d Min %d ftell = %d ",maxLen,minLen,ftell(compressFile));getchar(); fwrite(&codeNum, sizeof(short), 1, compressFile); //填写叶子编码压多少个 fwrite(&finalLength, sizeof(MyType), 1, compressFile); //最后剩 //printf("叶子共压：%d个,最后剩%d个 ",codeNum,finalLength); fseek(compressFile, 2 * LeafNum * sizeof(MyType) + codeNum, SEEK_CUR); //printf("开始正文ftell= %d 原文长%d ",ftell(compressFile),FileLength);getchar(); fseek(fp, 0, SEEK_SET); printf("Please wait a minute,compressing..."); while (count < FileLength) { ch = fgetc(fp); //fread(&ch,sizeof(MyType),1,fp); ++count; // printf("Read读 : %c 值 %d %s ",ch,ch,Map[ch]); for (p = Map[ch]; *p != ' '; p++) In_seqQueue(Q, *p); //printf(" Qlength: %d ",Q->length); while (Q->length > 8) // printf("OutQueue: "); { bits = GetBits(Q); //出队8个元素,合成一个字节 fputc(bits, compressFile); //fwrite(&bits,1,1,compressFile); Length++; // printf("压：%c ",bits); } } //end of while //最后一个bits ; finalLength = Q->length; //printf("最后剩Qlength:%d ",Q->length); n = 8 - finalLength; bits = GetBits(Q); //printf("最后Qlength:%d ",Q->length); for (i = 0; i < n; i++) bits = bits << 1; //以‘0’补 //fputc(bits,compressFile); fwrite(&bits, sizeof(MyType), 1, compressFile); //printf(" final压：%c ",bits); Length++; rewind(compressFile); //原文件长fwrite(&FileLength,sizeof(WeightType),1,compressFile); fwrite(&Length, sizeof(WeightType), 1, compressFile); //压缩后的长 fwrite(&finalLength, sizeof(char), 1, compressFile); //最后的串长 Length = Length + 12 + codeNum; //printf("原文件长 %ld;压缩后 %ld ",FileLength,Length); if (Length >= FileLength) puts(" Compression rate: 0.0%"); else printf(" Compression rate: %.2lf%c ", (double)((FileLength - Length) / (double)FileLength) * 100.0, '%'); fclose(fp); fclose(compressFile); free(Q); free(hc); free(Map); } //把读出的字符，转换成8个0、1字符串并入队 void ToQueue(SeqQueue * Q, MyType ch) { int i; MyType temp; for (i = 0; i < 8; i++) { temp = ch << i; temp = temp >> 7; if (1 == temp) In_seqQueue(Q, '1'); //printf("1"); else In_seqQueue(Q, '0'); //printf("0"); } //puts(""); } //解压缩 void UnCompress() { MyType *str, MaxLength, MinLength, ch, *num, finalLength = 0, final = 0; FILE *cf, *uf; short NLeaf, Ncom; char CName[N], UName[N], **hc, *p, x, *buf; SeqQueue *Q = NULL; int i, j; WeightType srcLen = 0, thisFile = 0; fflush(stdin); //清空输入缓冲区域 printf("filename to be uncompressed:"); scanf("%s", CName); if (CName[0] == ' ') { printf("try again:"); scanf("%s", CName); fflush(stdin); } fflush(stdin); //清空输入缓冲区域 printf("filename after uncompressed:"); scanf("%s", UName); if (UName[0] == ' ') { printf("try again:"); scanf("%s", UName); } cf = fopen(CName, "rb"); uf = fopen(UName, "wb"); if (!cf || !uf) { puts("Cannot open files."); return; } fread(&srcLen, sizeof(WeightType), 1, cf); //printf("压后文件长：%ld ",srcLen); fread(&finalLength, 1, 1, cf); // printf("原文件压剩:%d个 ",finalLength); fread(&NLeaf, sizeof(short), 1, cf); //printf("叶子:%d个 ",NLeaf); fread(&MaxLength, sizeof(MyType), 1, cf); fread(&MinLength, sizeof(MyType), 1, cf); //printf("MaxLength = %d;minLen= %d,Leaf= %d ",MaxLength,MinLength,NLeaf);getchar(); Q = (SeqQueue *)malloc(sizeof(SeqQueue)); buf = (char *)malloc((2 + MaxLength * sizeof(char))); str = (MyType *)malloc(NLeaf * sizeof(MyType)); num = (MyType *)malloc(NLeaf * sizeof(MyType)); //压缩叶子数量x和最后剩长 if (!Q || !str || !num || !buf) { puts("Memery error."); exit(1); } InitQueue(Q); //初始化 fread(&Ncom, sizeof(short), 1, cf); fread(&final, sizeof(MyType), 1, cf); for (i = 0; i < NLeaf; i++) //读取叶子及其码长 { fread(&str[i], sizeof(MyType), 1, cf); fread(&num[i], sizeof(MyType), 1, cf); //printf("chars= %c;num= %d ",Chars[i],CHlength[i]); } //printf("read ftell= %d ",ftell(cf));//getchar(); // printf(" 叶子码字压缩后%d个,最后剩%d个 ",Ncom,final); hc = (char **)malloc((NLeaf) * sizeof(char *)); //hc为编码表的指针数组 if (!hc) exit(1); --Ncom; //printf("开始取叶子编码ftell = %d Ncom=%d ",ftell(cf),Ncom); for (j = i = 0; i < Ncom; i++) { ch = fgetc(cf); //fread(&ch,1,1,cf); ToQueue(Q, ch); //printf("Q->Len= %d ",Q->length); while (Q->length > MaxLength) { hc[j] = p = (char *)malloc(1 + num[j]); for (ch = 0; ch < num[j]; ch++) { Out_Queue(Q, &x); *p++ = x; } *p = ' '; //printf("%c编 码%s ",str[j],hc[j]); j++; } } ch = fgetc(cf); //fread(&ch,1,1,cf);//最后一个 ToQueue(Q, ch); final = 8 - final; while (Q->length > final) { p = hc[j] = (char *)malloc(1 + num[j]); for (ch = 0; ch < num[j]; ch++) { Out_Queue(Q, &x); *p++ = x; } *p = ' '; //printf("%c编码%s ",str[j],hc[j]);getchar(); j++; } InitQueue(Q); --srcLen; --MinLength; //printf("开始解压正文%d ,压后长= %d ",ftell(cf),srcLen);getchar(); printf("Please wait a minute,uncompressing..."); while (thisFile < srcLen) { // printf("QLength= %d ",Q->length); ch = fgetc(cf); //fread(&ch,sizeof(MyType),1,cf); ToQueue(Q, ch); thisFile++; // printf("char:%c",ch); //完了后队列长于码串的最大值 while (Q->length > MaxLength) { for (i = 0; i < MinLength; i++) { Out_Queue(Q, &x); buf[i] = x; } for (; i < MaxLength; i++) { Out_Queue(Q, &x); buf[i] = x; buf[i + 1] = ' '; for (j = 0; j < NLeaf; j++) { if (i + 1 == num[j] && 0 == strcmp(hc[j], buf)) { ch = str[j]; //printf("出队 %s ",buf); fputc(ch, uf); //fwrite(&ch,1,1,uf);////printf("解 出：%c ",ch); break; } } if (j < NLeaf) break; } } //while MaxLength } ch = fgetc(cf); //fread(&ch,1,1,cf);//读取最后一个压缩字getchar(); ToQueue(Q, ch); finalLength = 8 - finalLength; while (Q->length > finalLength) { for (i = 0; i < MinLength; i++) { Out_Queue(Q, &x); buf[i] = x; } for (; i < MaxLength; i++) { Out_Queue(Q, &x); buf[i] = x; buf[i + 1] = ' '; for (j = 0; j < NLeaf; j++) { if (i + 1 == num[j] && 0 == strcmp(hc[j], buf)) { ch = str[j]; //printf("出 %s ",buf); fputc(ch, uf); //fwrite(&ch,1,1,uf);//printf("解 出：%c ",ch); break; } } if (j < NLeaf) break; } } //printf("Q->length= %d ",Q->length);printf("ftell= %d ",ftell(uf)); free(Q); free(str); free(num); free(hc); fclose(uf); fclose(cf); } int main(int argc, char *argv[]) { char choice, blank[] = " "; // writeFile(); system("color 8a"); while (1) { system("clear"); //清屏 puts(" * * * *Welcome use huffman encoder\decoder* * *"); puts(" **********************^_^***********************"); puts(" * *"); printf(" * %s 1 ]. Compress %s* ", blank, blank); puts(" * *"); printf(" * %s 2 ]. Uncompress%s * ", blank, blank); puts(" * *"); printf(" * %s 3 ]. Exit ^_^ %s * ", blank, blank); puts(" * *"); puts(" ************************************************"); printf (" (Apply to text file) Copyright 2011 By Bocai "); printf(" Choose (1 to 3):"); choice = getchar(); puts(""); getchar(); fflush(stdin); //清空输入缓冲区域，否则键入的回车符将作为程序结尾处的scanf输入，此函数在stdio.h中 switch (choice) { case '1': Compress(); printf("Press Enter to continue..."); getchar(); break; case '2': UnCompress(); printf(" Press Enter to continue..."); getchar(); break; case '3': return 0; break; } } return 0; } /*----------------------------END----------------------------------------*/