xref: /third_party/ffmpeg/libavcodec/mqc.h (revision cabdff1a) 
1/*
2 * MQ-coder: structures, common and decoder functions
3 * Copyright (c) 2007 Kamil Nowosad
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22#ifndef AVCODEC_MQC_H
23#define AVCODEC_MQC_H
24
25/**
26 * MQ-coder
27 * @file
28 * @author Kamil Nowosad
29 */
30
31#include <stdint.h>
32
33#define MQC_CX_UNI 17
34#define MQC_CX_RL  18
35
36extern const uint16_t ff_mqc_qe[2 * 47];
37extern const uint8_t  ff_mqc_nlps[2 * 47];
38extern const uint8_t  ff_mqc_nmps[2 * 47];
39
40typedef struct MqcState {
41    uint8_t *bp, *bpstart;
42    unsigned int a;
43    unsigned int c;
44    unsigned int ct;
45    uint8_t cx_states[19];
46    int raw;
47} MqcState;
48
49/* encoder */
50
51/** initialize the encoder */
52void ff_mqc_initenc(MqcState *mqc, uint8_t *bp);
53
54/** code bit d with context cx */
55void ff_mqc_encode(MqcState *mqc, uint8_t *cxstate, int d);
56
57/** flush the encoder [returns number of bytes encoded] */
58int ff_mqc_flush_to(MqcState *mqc, uint8_t *dst, int *dst_len);
59
60/* decoder */
61
62/**
63 * Initialize MQ-decoder.
64 * @param mqc   MQ decoder state
65 * @param bp    byte pointer
66 * @param raw   raw mode
67 * @param reset reset states
68 */
69void ff_mqc_initdec(MqcState *mqc, uint8_t *bp, int raw, int reset);
70
71/**
72 * MQ decoder.
73 * @param mqc       MQ decoder state
74 * @param cxstate   Context
75 * @return          Decision (0 to 1)
76 */
77int ff_mqc_decode(MqcState *mqc, uint8_t *cxstate);
78
79/* common */
80
81/**
82 * MQ-coder context initialisations.
83 * @param mqc       MQ-coder context
84 */
85void ff_mqc_init_contexts(MqcState *mqc);
86
87#endif /* AVCODEC_MQC_H */
88