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huffman: update to current coding style

This commit is contained in:
Luca Barbato 2012-08-27 12:29:34 +02:00
parent 125c6c0752
commit f76e47877c
1 changed files with 26 additions and 21 deletions
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47
libavcodec/huffman.c
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@ -31,24 +31,26 @@
#define HNODE -1
static void get_tree_codes(uint32_t *bits, int16_t *lens, uint8_t *xlat, Node *nodes, int node, uint32_t pfx, int pl, int *pos, int no_zero_count)
static void get_tree_codes(uint32_t *bits, int16_t *lens, uint8_t *xlat,
Node *nodes, int node,
uint32_t pfx, int pl, int *pos, int no_zero_count)
{
int s;
s = nodes[node].sym;
if(s != HNODE || (no_zero_count && !nodes[node].count)){
if (s != HNODE || (no_zero_count && !nodes[node].count)) {
bits[*pos] = pfx;
lens[*pos] = pl;
xlat[*pos] = s;
(*pos)++;
}else{
} else {
pfx <<= 1;
pl++;
get_tree_codes(bits, lens, xlat, nodes, nodes[node].n0, pfx, pl, pos,
no_zero_count);
get_tree_codes(bits, lens, xlat, nodes, nodes[node].n0, pfx, pl,
pos, no_zero_count);
pfx |= 1;
get_tree_codes(bits, lens, xlat, nodes, nodes[node].n0+1, pfx, pl, pos,
no_zero_count);
get_tree_codes(bits, lens, xlat, nodes, nodes[node].n0 + 1, pfx, pl,
pos, no_zero_count);
}
}
@ -60,7 +62,8 @@ static int build_huff_tree(VLC *vlc, Node *nodes, int head, int flags)
uint8_t xlat[256];
int pos = 0;
get_tree_codes(bits, lens, xlat, nodes, head, 0, 0, &pos, no_zero_count);
get_tree_codes(bits, lens, xlat, nodes, head, 0, 0,
&pos, no_zero_count);
return ff_init_vlc_sparse(vlc, 9, pos, lens, 2, 2, bits, 4, 4, xlat, 1, 1, 0);
}
@ -76,35 +79,37 @@ int ff_huff_build_tree(AVCodecContext *avctx, VLC *vlc, int nb_codes,
int cur_node;
int64_t sum = 0;
for(i = 0; i < nb_codes; i++){
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");
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){
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].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))))
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]);
FFSWAP(Node, nodes[j], nodes[j - 1]);
}
cur_node++;
}
if(build_huff_tree(vlc, nodes, nb_codes*2-2, flags) < 0){
if (build_huff_tree(vlc, nodes, nb_codes * 2 - 2, flags) < 0) {
av_log(avctx, AV_LOG_ERROR, "Error building tree\n");
return -1;
}