#include "statichuff.h"
+#include "../vfile/vfile.h"
+#include <stdlib.h>
-void putbit(char bit, char restart, char flush, FILE *fp)
+void putbit(char bit, char restart, char flush, VFILE *fp)
{
static unsigned long int bits_buffer = 0;
- static unsigned char bits_used = 0;
- int i;
+ static unsigned char bits_used = 0;
/* me obligan a emitir el output */
if ((flush == 1) && (bits_used > 0)) {
bits_buffer = bits_buffer << ((sizeof(unsigned long int)*8) - bits_used);
- fwrite(&bits_buffer,sizeof(unsigned long int),1,fp);
+ vfwrite(&bits_buffer,sizeof(unsigned long int),1,fp);
bits_buffer = 0;
bits_used = 0;
return;
/* lleno el buffer, escribo */
if (bits_used == 32) {
- fwrite(&bits_buffer,sizeof(unsigned long int),1,fp);
+ vfwrite(&bits_buffer,sizeof(unsigned long int),1,fp);
bits_buffer = 0;
bits_used = 0;
}
node1->rchild = node2->rchild;
}
-int shuff_compnode(SHUFFNODE *node1, SHUFFNODE *node2)
+int shuff_compnode(const void *node1, const void *node2)
{
- if (node1->freq < node2->freq) return 1;
- if (node1->freq > node2->freq) return -1;
+ if (((SHUFFNODE*)node1)->freq < ((SHUFFNODE*)node2)->freq) return 1;
+ if (((SHUFFNODE*)node1)->freq > ((SHUFFNODE*)node2)->freq) return -1;
return 0;
}
for (i = 0; i < 256; ++i) freqtable[i] = 0;
/* Abrimos el file */
- if ((fp = fopen(inputfile,"rb")) == NULL) return 0;
+ if ((fp = fopen(inputfile,"r")) == NULL) return 0;
while (!feof(fp)) {
/* Contamos las frecuencias */
symbol = fgetc(fp);
}
fclose(fp);
- return 1;
+ return 1;
}
SHUFFNODE *shuff_buildlist(t_freq *freqtable, int *nonzerofreqs)
SHUFFNODE *shuff_buildtree(SHUFFNODE *list, int listcount)
{
SHUFFNODE *lastsymbol = list+(listcount-1);
- SHUFFNODE *node1,*node2,*fictnode;
+ SHUFFNODE *node1,*node2;
- /* Ordenamos inicialmente la inputlist para tomar las dos freqs min */
while (lastsymbol > list) {
/* Ordeno la lista por frecuencia descendente */
qsort(list,listcount,sizeof(SHUFFNODE),shuff_compnode);
}
}
-
-
-int shuff_encode_symbols(t_freq *ftable, SHUFFCODE *ctable, char* inputfile, char *outputfile) {
-
- FILE *fpsource,*fpdest;
+int shuff_encode_symbols(t_freq *ftable, SHUFFCODE *ctable, char* inputfile, char *outputfile, long volsize)
+{
+ FILE *fpsource;
+ VFILE *fpdest;
int symbol,i;
unsigned long int sourcesize;
char bit;
SHUFFCODE symbolcode;
/* Abrimos el file */
- if ((fpsource = fopen(inputfile,"rb")) == NULL) return 0;
- if ((fpdest = fopen(outputfile,"wb")) == NULL) return 0;
+ if ((fpsource = fopen(inputfile,"r")) == NULL) return 0;
+ if ((fpdest = vfopen(outputfile,"w",volsize)) == NULL) return 0;
/* Guardamos el size el archivo original e inputlist como header */
fseek(fpsource,0,SEEK_END);
sourcesize = ftell(fpsource);
- fwrite(&sourcesize,sizeof(unsigned long int),1,fpdest);
- fwrite(ftable,sizeof(t_freq),256,fpdest);
+ vfwrite(&sourcesize,sizeof(unsigned long int),1,fpdest);
+ vfwrite(ftable,sizeof(t_freq),256,fpdest);
/* Encodeo */
fseek(fpsource,0,SEEK_SET);
/* Hacemos un flush de lo que haya quedado en el buffer de salida */
putbit(0,0,1,fpdest);
fclose(fpsource);
- fclose(fpdest);
+ vfclose(fpdest);
return 1;
}
-int shuff_encode_file(char *inputfile, char *outputfile)
+int shuff_encode_file(char *inputfile, char *outputfile, long volsize)
{
/* Locals */
t_freq *freqtable = (t_freq*)malloc(sizeof(t_freq)*256);
SHUFFNODE *inputlist;
SHUFFNODE *codetree;
SHUFFCODE *codetable = (SHUFFCODE*)malloc(sizeof(SHUFFCODE)*256);
- int freqcount = 0,i;
+ int freqcount = 0;
/* Armamos la tabla de frecuencias */
- if (!shuff_scanfreq(inputfile,freqtable)) return -1;
+ if (!shuff_scanfreq(inputfile,freqtable)) return 0;
/* Armo el input list y genero el arbol de huffman */
inputlist = shuff_buildlist(freqtable, &freqcount);
/* Armo la tabla de codigos prefijos para el encoder */
shuff_zerocodes(codetable);
shuff_buildcodes(codetable,codetree,0,0);
- shuff_printcodes(codetable,freqtable);
+ /*shuff_printcodes(codetable,freqtable);*/
/* Encodeo byte per byte */
- shuff_encode_symbols(freqtable,codetable,inputfile,outputfile);
+ shuff_encode_symbols(freqtable,codetable,inputfile,outputfile,volsize);
+
+ /* Free up memory baby yeah */
+ free(freqtable);
+ free(inputlist);
+ free(codetable);
+
+ return 1;
+}
+
+SHUFFNODE *shuff_decode_symbols(SHUFFNODE *entrynode, unsigned long int buffer,
+ int *bitsleft, unsigned short int *symbol)
+{
+ char bit = 0;
+
+ /* Levanto el symbolo y si es uno valido, devuelvo */
+ *symbol = entrynode->symbol;
+ if (*symbol != 256) return entrynode;
+ if (*bitsleft == 0) return entrynode;
+
+ /* Obtengo otro bit a procesar y me muevo en el arbol */
+ bit = (buffer >> ((*bitsleft)-1)) & 1;
+ --(*bitsleft);
+ if (bit == 0) return shuff_decode_symbols(entrynode->lchild,buffer,bitsleft,symbol);
+ else return shuff_decode_symbols(entrynode->rchild,buffer,bitsleft,symbol);
}
-int shuff_decode(char *inputfile, char *outputfile)
+int shuff_decode_file(char *inputfile, char *outputfile)
{
SHUFFNODE *inputlist;
- SHUFFNODE *codetree;
+ SHUFFNODE *codetree,*currnode;
t_freq *ftable = (t_freq*)malloc(sizeof(t_freq)*256);
- unsigned long int bytesleft;
- FILE *fpsource;
+ unsigned long int bytesleft,codebuffer;
+ VFILE *fpsource;
FILE *fpdest;
- int i,freqcount = 0;
+ unsigned short int decoded_symbol;
+ int bitsleft,freqcount = 0;
/* Levanto cuantos bytes decodeo y la freq table */
- if ((fpsource = fopen(inputfile,"rb")) == NULL) return 0;
- if ((fpdest = fopen(outputfile,"wb")) == NULL) return 0;
- fread(&bytesleft,sizeof(unsigned long int),1,fpsource);
- fread(ftable,sizeof(unsigned long int),256,fpsource);
+ if ((fpsource = vfopen(inputfile,"r",0)) == NULL) return 0;
+ if ((fpdest = fopen(outputfile,"w")) == NULL) return 0;
+ vfread(&bytesleft,sizeof(unsigned long int),1,fpsource);
+ vfread(ftable,sizeof(unsigned long int),256,fpsource);
inputlist = shuff_buildlist(ftable, &freqcount);
codetree = shuff_buildtree(inputlist,freqcount);
+ currnode = codetree;
+
+ while (!feof(fpsource->fp) && (bytesleft > 0)) {
- fclose(fpsource);
+ /* Leo un buffer de 32 bits */
+ if (vfread(&codebuffer,sizeof(unsigned long int),1,fpsource) != 1) continue;
+ bitsleft = sizeof(unsigned long int) * 8;
+
+ /* Proceso el buffer sacando simbolos hasta que se me agote */
+ while ((bitsleft > 0) && (bytesleft > 0)) {
+ currnode = shuff_decode_symbols(currnode,codebuffer,&bitsleft,&decoded_symbol);
+ /* Si obtuve un symbolo valido lo emito*/
+ if (decoded_symbol != 256) {
+ fputc(decoded_symbol,fpdest);
+ currnode = codetree;
+ --bytesleft;
+ }
+ }
+ }
+
+ vfclose(fpsource);
fclose(fpdest);
+ /* Free up memory baby yeah */
+ free(ftable);
+ free(inputlist);
-}
-
-int main(int argc, char* argv[])
-{
- if (argc == 1) return -1;
-
- /* Comprimo */
- shuff_encode_file(argv[1],"output.shf");
-
- /* Decodeo */
- shuff_decode("output.shf","decoded.dat");
-
- return 0;
+ return 1;
}
projects / z.facultad / 75.06 / jacu.git / blobdiff