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-rw-r--r--libavcodec/huffman.c114
1 files changed, 57 insertions, 57 deletions
diff --git a/libavcodec/huffman.c b/libavcodec/huffman.c
index c8d37d78b6..27fed9f022 100644
--- a/libavcodec/huffman.c
+++ b/libavcodec/huffman.c
@@ -31,6 +31,63 @@
/* symbol for Huffman tree node */
#define HNODE -1
+typedef struct {
+ uint64_t val;
+ int name;
+} HeapElem;
+
+static void heap_sift(HeapElem *h, int root, int size)
+{
+ while (root * 2 + 1 < size) {
+ int child = root * 2 + 1;
+ if (child < size - 1 && h[child].val > h[child+1].val)
+ child++;
+ if (h[root].val > h[child].val) {
+ FFSWAP(HeapElem, h[root], h[child]);
+ root = child;
+ } else
+ break;
+ }
+}
+
+void ff_huff_gen_len_table(uint8_t *dst, const uint64_t *stats)
+{
+ HeapElem h[256];
+ int up[2*256];
+ int len[2*256];
+ int offset, i, next;
+ int size = 256;
+
+ for (offset = 1; ; offset <<= 1) {
+ for (i=0; i < size; i++) {
+ h[i].name = i;
+ h[i].val = (stats[i] << 8) + offset;
+ }
+ for (i = size / 2 - 1; i >= 0; i--)
+ heap_sift(h, i, size);
+
+ for (next = size; next < size * 2 - 1; next++) {
+ // merge the two smallest entries, and put it back in the heap
+ uint64_t min1v = h[0].val;
+ up[h[0].name] = next;
+ h[0].val = INT64_MAX;
+ heap_sift(h, 0, size);
+ up[h[0].name] = next;
+ h[0].name = next;
+ h[0].val += min1v;
+ heap_sift(h, 0, size);
+ }
+
+ len[2 * size - 2] = 0;
+ for (i = 2 * size - 3; i >= size; i--)
+ len[i] = len[up[i]] + 1;
+ for (i = 0; i < size; i++) {
+ dst[i] = len[up[i]] + 1;
+ if (dst[i] >= 32) break;
+ }
+ if (i==size) break;
+ }
+}
static void get_tree_codes(uint32_t *bits, int16_t *lens, uint8_t *xlat,
Node *nodes, int node,
@@ -117,60 +174,3 @@ int ff_huff_build_tree(AVCodecContext *avctx, VLC *vlc, int nb_codes,
}
return 0;
}
-
-typedef struct {
- uint64_t val;
- int name;
-} HeapElem;
-
-static void heap_sift(HeapElem *h, int root, int size)
-{
- while(root*2+1 < size) {
- int child = root*2+1;
- if(child < size-1 && h[child].val > h[child+1].val)
- child++;
- if(h[root].val > h[child].val) {
- FFSWAP(HeapElem, h[root], h[child]);
- root = child;
- } else
- break;
- }
-}
-
-void ff_generate_len_table(uint8_t *dst, const uint64_t *stats){
- HeapElem h[256];
- int up[2*256];
- int len[2*256];
- int offset, i, next;
- int size = 256;
-
- for(offset=1; ; offset<<=1){
- for(i=0; i<size; i++){
- h[i].name = i;
- h[i].val = (stats[i] << 8) + offset;
- }
- for(i=size/2-1; i>=0; i--)
- heap_sift(h, i, size);
-
- for(next=size; next<size*2-1; next++){
- // merge the two smallest entries, and put it back in the heap
- uint64_t min1v = h[0].val;
- up[h[0].name] = next;
- h[0].val = INT64_MAX;
- heap_sift(h, 0, size);
- up[h[0].name] = next;
- h[0].name = next;
- h[0].val += min1v;
- heap_sift(h, 0, size);
- }
-
- len[2*size-2] = 0;
- for(i=2*size-3; i>=size; i--)
- len[i] = len[up[i]] + 1;
- for(i=0; i<size; i++) {
- dst[i] = len[up[i]] + 1;
- if(dst[i] >= 32) break;
- }
- if(i==size) break;
- }
-}