X-Git-Url: https://git.llucax.com/z.facultad/75.06/jacu.git/blobdiff_plain/d5a4d5447b65cfb33f907f0422d970ed880d82a6..64cd44addd33d589c56bf7c6b669f3a9b2c2a410:/src/statichuff/statichuff.c diff --git a/src/statichuff/statichuff.c b/src/statichuff/statichuff.c index e1dfe35..6d6de7f 100644 --- a/src/statichuff/statichuff.c +++ b/src/statichuff/statichuff.c @@ -5,8 +5,7 @@ void putbit(char bit, char restart, char flush, FILE *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)) { @@ -43,10 +42,10 @@ void shuff_cpynode(SHUFFNODE *node1, SHUFFNODE *node2) 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; } @@ -120,9 +119,8 @@ 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); @@ -193,8 +191,8 @@ void shuff_buildcodes(SHUFFCODE *table, SHUFFNODE *node, int level, int code) -int shuff_encode_symbols(t_freq *ftable, SHUFFCODE *ctable, char* inputfile, char *outputfile) { - +int shuff_encode_symbols(t_freq *ftable, SHUFFCODE *ctable, char* inputfile, char *outputfile) +{ FILE *fpsource,*fpdest; int symbol,i; unsigned long int sourcesize; @@ -240,10 +238,10 @@ int shuff_encode_file(char *inputfile, char *outputfile) 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); @@ -252,45 +250,81 @@ int shuff_encode_file(char *inputfile, char *outputfile) /* 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); + + /* Free up memory baby yeah */ + free(freqtable); + free(inputlist); + free(codetable); + + return 1; } -int shuff_decode(char *inputfile, char *outputfile) +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_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; + unsigned long int bytesleft,codebuffer; FILE *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); + fread(ftable,sizeof(unsigned long int),256,fpsource); inputlist = shuff_buildlist(ftable, &freqcount); codetree = shuff_buildtree(inputlist,freqcount); + currnode = codetree; + + while (!feof(fpsource) && (bytesleft > 0)) { + + /* Leo un buffer de 32 bits */ + if (fread(&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; + } + } + } fclose(fpsource); fclose(fpdest); + /* Free up memory baby yeah */ + free(ftable); + free(inputlist); + return 1; } -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; -}