82 lines
1.9 KiB
C
82 lines
1.9 KiB
C
#include <assert.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include "compressor.h"
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#define BUFSIZE 1024
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int ByteRLEEncode(char* bufferIn, int size, char* bufferOut) {
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int posIn = 0, count = 1, posOut = 0;
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char byteCurrent, byteRLE = bufferIn[posIn++];
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while (posIn != size) {
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byteCurrent = bufferIn[posIn++];
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if (byteCurrent == byteRLE) {
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count++;
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if (count == 256) {
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bufferOut[posOut++] = byteRLE;
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bufferOut[posOut++] = 255;
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count = 1;
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}
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} else {
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bufferOut[posOut++] = byteRLE;
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bufferOut[posOut++] = count;
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byteRLE = byteCurrent;
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count = 1;
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}
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}
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bufferOut[posOut++] = byteRLE;
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bufferOut[posOut++] = count;
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return posOut;
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}
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int mycompress(char* bufferIn, int size, char* bufferOut){
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return ByteRLEEncode(bufferIn, size, bufferOut);;
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}
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void compress(FILE *infile, FILE *outfile){
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char buffer[BUFSIZE];
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memset(buffer,0,BUFSIZE);
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while(1){
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int insize = fread(buffer,sizeof(char),BUFSIZE,infile);
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if (insize == 0){
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if (feof(infile)){
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// end of file
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break;
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}
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assert(!ferror(infile));
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}
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char outbuf[BUFSIZE*2];
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// Doplnte implementaciu kompresie.
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int outsize = mycompress(buffer,insize,outbuf);
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if (outsize > 0){
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fwrite(outbuf,sizeof(char),outsize,outfile);
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}
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}
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}
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void decompress(FILE *infile, FILE *outfile){
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unsigned char RLEMetadata[2];
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char RLEData[255];
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while (fread(RLEMetadata, 2, 1, infile)) {
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printf("%c %d\n", RLEMetadata[0], RLEMetadata[1]);
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for (int i = 0; i < RLEMetadata[1]; i++) {
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RLEData[i] = RLEMetadata[0];
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}
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fwrite(RLEData, RLEMetadata[1], 1, outfile);
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}
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}
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