用C語言編寫程式實現Zip或者Rar無損壓縮演算法

用C語言編寫程式實現Zip或者Rar無損壓縮演算法

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * **                                                                  **HUFF.C Huffman encode for multimedia application 8*8 pixel Ver 3  **                                                                  **Ver 1:  Complied in Borland Turbo C++ 3.0                         **Ver 2:  Complied in Microsoft Visual C++ 6.0                      **Ver 3:  Complied in Microsoft Visual C++ 6.0                      **          add code to print code table of the compression         **          print output message in Chinese                         **                                                                  **by Lee Meitz, Solid Mechanics, Huazhong Univ of Sci and Tech      **2001.11.15 - 2001.12.27                                           ** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */#include <stdio.h>#include <stdlib.h>#include <time.h>#define  DNUM 64    //define data number 8*8#define  LOOP 10000 //times of compressiontypedef struct{    unsigned short weight, data;    unsigned short parent, lchild, rchild;} HuffNode;typedef struct{    unsigned char code;    unsigned short codelength;} HuffCode;unsigned int fCount[256] = {0};unsigned int data_num;unsigned int code_size;unsigned int last_bit;void FrequencyCount(unsigned char*);         //頻率統計void HuffSelect(HuffNode*, int, int*, int*); //從結點中選出權最小的兩個節點void HuffmanCodeTable(HuffNode*, HuffCode*); //構造huffman樹，產生huffman編碼錶void HuffmanCompress(unsigned char*, unsigned char *, HuffCode*); //壓縮資料void BitPrint(unsigned char*);               //按位列印結果，用於調試void main(){    int i, j, loop;                               //variable for loop    HuffNode hfdata[2*DNUM] = {{0, 0, 0, 0, 0}};  //Huffman node    HuffCode code_table[256] = {{0, 0}};          //code table will be searched by subscript    unsigned char hfcode[2*DNUM];                 //output code    time_t time1, time2;/*  unsigned char pixel[DNUM] = {    1,2,3,4, 1,2,3,4, 1,2,3,4, 1,1,1,1};*//*  unsigned char pixel[DNUM] = {        139,144,149,153,155,155,155,155,        144,151,153,156,159,156,156,156,        150,155,160,163,158,156,156,156,        159,161,162,160,160,159,159,159,        159,160,161,162,162,155,155,155,        161,161,161,161,160,157,157,157,        162,162,161,163,162,157,157,157,        162,162,161,161,163,158,158,158};*/    unsigned char pixel[DNUM] = { //random data        141, 101, 126, 111, 163, 112, 133, 156,        103, 144, 111, 176, 117, 120, 188, 187,        175, 164, 190, 156, 112, 179, 142, 119,        140, 111, 127, 186, 196, 190, 189, 127,        185, 103, 185, 110, 192, 139, 159, 104,        151, 193, 178, 198, 114, 170, 179, 149,        124, 149, 165, 108, 141, 176, 113, 164,        101, 140, 120, 126, 173, 189, 158, 184};/*  unsigned char pixel[DNUM] = {        202, 221, 159, 183, 41, 136, 247, 66,        146, 29, 101, 108, 45, 61, 210, 236,        90, 130, 54, 66, 132, 206, 119, 232,        184, 135, 96, 78, 120, 41, 231, 203,        150, 94, 172, 142, 122, 180, 150, 204,        232, 121, 180, 221, 3, 207, 115, 147,        72, 149, 169, 121, 76, 208, 235, 43,        107, 58, 0, 237, 197, 7, 210, 89};*/    FrequencyCount(pixel);    time1 = time(NULL);    for (loop=0; loop<LOOP; loop++) {        //set huffman nodes data and weight, i=0:255, j=1:64        for (i=0, j=1, data_num=0; i<256; i++) {            if (fCount[i]) {                hfdata[j].weight = fCount[i];                hfdata[j++].data = i;                data_num ++;            }        }        //build huffman tree and generate huffman code table        HuffmanCodeTable(hfdata, code_table);        //compress source data to huffman code using code table        HuffmanCompress(pixel, hfcode, code_table);        //initial hfdata and code_table        for (j=0; j<2*DNUM; j++) {            hfdata[j].data=0;            hfdata[j].lchild=0;            hfdata[j].parent=0;            hfdata[j].rchild=0;            hfdata[j].weight=0;        }    }    time2 = time(NULL);    //conclude    printf("\n哈夫曼編碼壓縮圖塊，壓縮報告\n華中科技大學力學系：李美之\n");    printf("\n◎來源資料（%d位元組）:\n ", DNUM);    for (i=0; i<DNUM; i++) {        printf(i%8==7 ? "%02X\n " : "%02X ", pixel[i]);    }    printf("\n◎壓縮資料（%d位元組）:\n ", code_size);    for (i=0; i<code_size; i++) {        printf(i%8==7 ? "%02X\n " : "%02X ", hfcode[i]);    }    //列印碼錶    printf("\n\n◎碼錶－編碼字典（%d項）\n", data_num);    for (i=0; i<256; i++) {        if (code_table[i].codelength) {            printf("%3d|%02X: ", i, i);            for (j=0; j<code_table[i].codelength; j++) {                printf("%d", ((code_table[i].code << j)&0x80)>>7);            }            printf("\t");        }    }    printf("\n\n◎壓縮率：%2.0f%% \t壓縮時間：%.3f毫秒\n",(float)code_size/DNUM * 100, 1E3*(time2-time1)/LOOP);}void BitPrint(unsigned char *hfcode){    int i, j;    int endbit = last_bit;    unsigned char thebyte;    for (i=0; i < code_size-1; i++) {        thebyte = hfcode[i];        for (j=0; j<8; j++) {            printf("%d", ((thebyte<<j)&0x80)>>7);        }    }    if (last_bit == 7) {        endbit = -1;    }    thebyte = hfcode[i];    for (j=7; j>endbit; j--) {        printf("%d", ((thebyte<<(7-j))&0x80)>>7);    }}void HuffmanCompress(unsigned char *pixel, unsigned char *hfcode, HuffCode * code_table){    int i, j;    int curbit=7; //current bit in _thebyte_    unsigned int bytenum=0; //number of destination code can also be position of byte processed in destination    unsigned int ptbyte=0; //position of byte processed in destination    unsigned int curlength; //code's length of _curcode_    unsigned char curcode; //current byte's huffman code    unsigned char thebyte=0; //destination byte write    unsigned char value; //current byte's value (pixel[])    //process every byte    for (i=0; i<DNUM; i++) {        value = pixel[i];        curcode = (code_table[value]).code;        curlength = (code_table[value]).codelength;        //move out every bit from curcode to destination        for (j=0;j<=curlength;j++) {            if ((curcode<<j)&0x80) {                thebyte |= (unsigned char)(0x01<<curbit);            }            curbit --;            if (curbit < 0) {                hfcode[ptbyte++] = thebyte;                thebyte = 0;                curbit  = 7;                bytenum ++;            }        }    }    //think about which bit is the end    if (curbit != 7) {        hfcode[ptbyte] = thebyte;        bytenum ++;    }    code_size = bytenum;    last_bit  = curbit;}void HuffmanCodeTable(HuffNode *hfdata, HuffCode *code_table){    int i, j; //variable for loop    int tree_num = 2*data_num - 1; //node of huffman tree    int min1, min2; //two minimum weight    int p; //the id of parent node    unsigned char curcode; //current code being processing    int curlength; //current code's length    //build huffman tree    for (i=data_num; i<tree_num; i++) {        HuffSelect(hfdata, i, &min1, &min2);        hfdata[min1].parent = i+1;        hfdata[min2].parent = i+1;        hfdata[i+1].lchild = min1;        hfdata[i+1].rchild = min2;        hfdata[i+1].weight = hfdata[min1].weight + hfdata[min2].weight;    }    //generate huffman code    //i present the i th code, j present from leaf to root in huffman tree    //hfdata[i].data (0:255) is a byte number    //編碼從葉讀到根，按位從高往低壓入一個位元組，讀編碼從左向右    for (i=1; i<=data_num; i++) {        curcode = 0;        curlength = 0;        for (j=i, p=hfdata[j].parent; p!=0; j=p, p=hfdata[j].parent) {            curlength ++;            if (j==hfdata[p].lchild) curcode >>= 1;            else curcode = (curcode >> 1) | 0x80; //0x80 = 128 = B1000 0000        }        code_table[hfdata[i].data].code = curcode;        code_table[hfdata[i].data].codelength = curlength;    }}void HuffSelect(HuffNode *hfdata, int end, int *min1, int *min2){    int i; //variable for loop    int s1, s2;    HuffNode wath[30];    for (i=0; i<30; i++) {        wath[i] = hfdata[i];    }    s1 = s2 = 1;    while (hfdata[s1].parent) {        s1++;    }    for (i=2; i<=end; i++) {        if (hfdata[i].parent == 0 && hfdata[i].weight < hfdata[s1].weight) {            s1 = i;        }    }    while (hfdata[s2].parent || s1 == s2) {        s2++;    }    for (i=1; i<=end; i++) {        if (hfdata[i].parent ==0 && hfdata[i].weight < hfdata[s2].weight && (i - s1)) {            s2 = i;        }    }    *min1 = s1;    *min2 = s2;}void FrequencyCount(unsigned char *chs){    int i;    for (i=0; i<DNUM; i++) {        fCount[*(chs+i)] ++;    }}