extern void compress_huffman(FILE *fin, char ArchiveName[200], int fileCount)
{
unsigned long int *frequency = (unsigned long int*)calloc(CHARS_NUM, sizeof(unsigned long int));
count_frequency(fin, frequency);
huff_node_t *root = build_huff_tree(frequency);
int
**codes = (int**)malloc(CHARS_NUM * sizeof(int*)),
*code_lengths = (int*)calloc(CHARS_NUM, sizeof(int));
_codes(root, codes, code_lengths);
FILE *fout = fopen(strncat(ArchiveName, ".vlt", 4), "w");
fprintf(fout, "UPA File Archive\nsign: UPA\nHUFF\n1\n%d\n", fileCount);
codify(fin, root, codes, code_lengths, fout);
}
/**
* nodes size must be 2*nb_codes
* first nb_codes nodes.count must be set
*/
int ff_huff_build_tree(AVCodecContext *avctx, VLC *vlc, int nb_codes,
Node *nodes, HuffCmp cmp, int flags)
{
int i, j;
int cur_node;
int64_t sum = 0;
for(i = 0; i < nb_codes; i++)
{
nodes[i].sym = i;
nodes[i].n0 = -2;
sum += nodes[i].count;
}
if(sum >> 31)
{
av_log(avctx, AV_LOG_ERROR, "Too high symbol frequencies. Tree construction is not possible\n");
return -1;
}
qsort(nodes, nb_codes, sizeof(Node), cmp);
cur_node = nb_codes;
nodes[nb_codes*2-1].count = 0;
for(i = 0; i < nb_codes * 2 - 1; i += 2)
{
nodes[cur_node].sym = HNODE;
nodes[cur_node].count = nodes[i].count + nodes[i+1].count;
nodes[cur_node].n0 = i;
for(j = cur_node; j > 0; j--)
{
if(nodes[j].count > nodes[j-1].count ||
(nodes[j].count == nodes[j-1].count &&
(!(flags & FF_HUFFMAN_FLAG_HNODE_FIRST) ||
nodes[j].n0 == j - 1 || nodes[j].n0 == j - 2 ||
(nodes[j].sym != HNODE && nodes[j-1].sym != HNODE))))
break;
FFSWAP(Node, nodes[j], nodes[j-1]);
}
cur_node++;
}
if(build_huff_tree(vlc, nodes, nb_codes * 2 - 2, flags) < 0)
{
av_log(avctx, AV_LOG_ERROR, "Error building tree\n");
return -1;
}
return 0;
}
/**
* nodes size must be 2*nb_codes
* first nb_codes nodes.count must be set
*/
int ff_huff_build_tree(AVCodecContext *avctx, VLC *vlc, int nb_codes,
Node *nodes, HuffCmp cmp, int flags)
{
int i, j;
int cur_node;
int64_t sum = 0;
for(i = 0; i < nb_codes; i++){
nodes[i].sym = i;
nodes[i].n0 = -2;
sum += nodes[i].count;
}
if(sum >> 31) {
av_log(avctx, AV_LOG_ERROR, "Too high symbol frequencies. Tree construction is not possible\n");
return -1;
}
qsort(nodes, nb_codes, sizeof(Node), cmp);
cur_node = nb_codes;
nodes[nb_codes*2-1].count = 0;
for(i = 0; i < nb_codes*2-1; i += 2){
uint32_t cur_count = nodes[i].count + nodes[i+1].count;
// find correct place to insert new node, and
// make space for the new node while at it
for(j = cur_node; j > i + 2; j--){
if(cur_count > nodes[j-1].count ||
(cur_count == nodes[j-1].count &&
!(flags & FF_HUFFMAN_FLAG_HNODE_FIRST)))
break;
nodes[j] = nodes[j - 1];
}
nodes[j].sym = HNODE;
nodes[j].count = cur_count;
nodes[j].n0 = i;
cur_node++;
}
if(build_huff_tree(vlc, nodes, nb_codes*2-2, flags) < 0){
av_log(avctx, AV_LOG_ERROR, "Error building tree\n");
return -1;
}
return 0;
}