d56c7274b0ea4598f8c5dced1ed148af775a3cf9
[libav.git] / libavcodec / huffman.h
1 /**
2 * @file libavcodec/huffman.h
3 * huffman tree builder and VLC generator
4 * Copyright (C) 2007 Aurelien Jacobs <aurel@gnuage.org>
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23 #ifndef AVCODEC_HUFFMAN_H
24 #define AVCODEC_HUFFMAN_H
25
26 #include "avcodec.h"
27 #include "get_bits.h"
28
29 typedef struct {
30 int16_t sym;
31 int16_t n0;
32 uint32_t count;
33 } Node;
34
35 #define FF_HUFFMAN_FLAG_HNODE_FIRST 0x01
36 #define FF_HUFFMAN_FLAG_ZERO_COUNT 0x02
37
38 typedef int (*HuffCmp)(const void *va, const void *vb);
39 int ff_huff_build_tree(AVCodecContext *avctx, VLC *vlc, int nb_codes,
40 Node *nodes, HuffCmp cmp, int flags);
41
42 #endif /* AVCODEC_HUFFMAN_H */