ffmpeg/libavcodec/mqc.h

   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
  36 extern uint16_t ff_mqc_qe[2 * 47];
  37 extern uint8_t  ff_mqc_nlps[2 * 47];
  38 extern uint8_t  ff_mqc_nmps[2 * 47];
  39
  40 typedef 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 } MqcState;
  47
  48 /* encoder */
  49
  50 /** initialize the encoder */
  51 void ff_mqc_initenc(MqcState *mqc, uint8_t *bp);
  52
  53 /** code bit d with context cx */
  54 void ff_mqc_encode(MqcState *mqc, uint8_t *cxstate, int d);
  55
  56 /** number of encoded bytes */
  57 int ff_mqc_length(MqcState *mqc);
  58
  59 /** flush the encoder [returns number of bytes encoded] */
  60 int ff_mqc_flush(MqcState *mqc);
  61
  62 /* decoder */
  63
  64 /**
  65  * Initialize MQ-decoder.
  66  * @param mqc   MQ decoder state
  67  * @param bp    byte poiter
  68  */
  69 void ff_mqc_initdec(MqcState *mqc, uint8_t *bp);
  70
  71 /**
  72  * MQ decoder.
  73  * @param mqc       MQ decoder state
  74  * @param cxstate   Context
  75  * @return          Decision (0 ot 1)
  76  */
  77 int ff_mqc_decode(MqcState *mqc, uint8_t *cxstate);
  78
  79 /* common */
  80
  81 /**
  82  * MQ-coder Initialize context tables (QE, NLPS, NMPS)
  83  */
  84 void ff_mqc_init_context_tables(void);
  85
  86 /**
  87  * MQ-coder context initialisations.
  88  * @param mqc       MQ-coder context
  89  */
  90 void ff_mqc_init_contexts(MqcState *mqc);
  91
  92 #endif /* AVCODEC_MQC_H */