diff options
Diffstat (limited to 'libavcodec/huffman.c')
| -rw-r--r-- | libavcodec/huffman.c | 37 |
1 files changed, 19 insertions, 18 deletions
diff --git a/libavcodec/huffman.c b/libavcodec/huffman.c index dec2197fc9..8dd356dde4 100644 --- a/libavcodec/huffman.c +++ b/libavcodec/huffman.c @@ -2,20 +2,20 @@ * Copyright (c) 2006 Konstantin Shishkov * Copyright (c) 2007 Loren Merritt * - * This file is part of Libav. + * This file is part of FFmpeg. * - * Libav is free software; you can redistribute it and/or + * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * - * Libav is distributed in the hope that it will be useful, + * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public - * License along with Libav; if not, write to the Free Software + * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ @@ -114,7 +114,7 @@ static void get_tree_codes(uint32_t *bits, int16_t *lens, uint8_t *xlat, } } -static int build_huff_tree(VLC *vlc, Node *nodes, int head, int flags) +static int build_huff_tree(VLC *vlc, Node *nodes, int head, int flags, int nb_bits) { int no_zero_count = !(flags & FF_HUFFMAN_FLAG_ZERO_COUNT); uint32_t bits[256]; @@ -124,7 +124,7 @@ static int build_huff_tree(VLC *vlc, Node *nodes, int head, int flags) 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); + return ff_init_vlc_sparse(vlc, nb_bits, pos, lens, 2, 2, bits, 4, 4, xlat, 1, 1, 0); } @@ -132,7 +132,7 @@ static int build_huff_tree(VLC *vlc, Node *nodes, int head, int flags) * 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, +int ff_huff_build_tree(AVCodecContext *avctx, VLC *vlc, int nb_codes, int nb_bits, Node *nodes, HuffCmp cmp, int flags) { int i, j; @@ -155,21 +155,22 @@ int ff_huff_build_tree(AVCodecContext *avctx, VLC *vlc, int nb_codes, 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)))) + 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; - FFSWAP(Node, nodes[j], nodes[j - 1]); + 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) { + if (build_huff_tree(vlc, nodes, nb_codes * 2 - 2, flags, nb_bits) < 0) { av_log(avctx, AV_LOG_ERROR, "Error building tree\n"); return -1; } |