ffmpeg/libavcodec/rl.h

   1 /*
   2  * Copyright (c) 2000-2002 Fabrice Bellard
   3  * Copyright (c) 2002-2004 Michael Niedermayer
   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 /**
  23  * @file
  24  * rl header.
  25  */
  26
  27 #ifndef AVCODEC_RL_H
  28 #define AVCODEC_RL_H
  29
  30 #include <stdint.h>
  31 #include "get_bits.h"
  32
  33 /* run length table */
  34 #define MAX_RUN    64
  35 #define MAX_LEVEL  64
  36
  37 /** RLTable. */
  38 typedef struct RLTable {
  39     int n;                         ///< number of entries of table_vlc minus 1
  40     int last;                      ///< number of values for last = 0
  41     const uint16_t (*table_vlc)[2];
  42     const int8_t *table_run;
  43     const int8_t *table_level;
  44     uint8_t *index_run[2];         ///< encoding only
  45     int8_t *max_level[2];          ///< encoding & decoding
  46     int8_t *max_run[2];            ///< encoding & decoding
  47     RL_VLC_ELEM *rl_vlc[32];       ///< decoding only
  48 } RLTable;
  49
  50 /**
  51  *
  52  * @param static_store static uint8_t array[2][2*MAX_RUN + MAX_LEVEL + 3] which will hold
  53  *                     the level and run tables, if this is NULL av_malloc() will be used
  54  */
  55 void ff_init_rl(RLTable *rl, uint8_t static_store[2][2*MAX_RUN + MAX_LEVEL + 3]);
  56 void ff_init_vlc_rl(RLTable *rl, unsigned static_size);
  57
  58 #define INIT_VLC_RL(rl, static_size)\
  59 {\
  60     int q;\
  61     static RL_VLC_ELEM rl_vlc_table[32][static_size];\
  62 \
  63     if(!rl.rl_vlc[0]){\
  64         for(q=0; q<32; q++)\
  65             rl.rl_vlc[q]= rl_vlc_table[q];\
  66 \
  67         ff_init_vlc_rl(&rl, static_size);\
  68     }\
  69 }
  70
  71 static inline int get_rl_index(const RLTable *rl, int last, int run, int level)
  72 {
  73     int index;
  74     index = rl->index_run[last][run];
  75     if (index >= rl->n)
  76         return rl->n;
  77     if (level > rl->max_level[last][run])
  78         return rl->n;
  79     return index + level - 1;
  80 }
  81
  82 #endif /* AVCODEC_RL_H */