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 Libav.
   6  *
   7  * Libav 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  * Libav 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 Libav; 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
  32 #include "vlc.h"
  33
  34 /* run length table */
  35 #define MAX_RUN    64
  36 #define MAX_LEVEL  64
  37
  38 /** RLTable. */
  39 typedef struct RLTable {
  40     int n;                         ///< number of entries of table_vlc minus 1
  41     int last;                      ///< number of values for last = 0
  42     const uint16_t (*table_vlc)[2];
  43     const int8_t *table_run;
  44     const int8_t *table_level;
  45     uint8_t *index_run[2];         ///< encoding only
  46     int8_t *max_level[2];          ///< encoding & decoding
  47     int8_t *max_run[2];            ///< encoding & decoding
  48     VLC vlc;                       ///< decoding only deprecated FIXME remove
  49     RL_VLC_ELEM *rl_vlc[32];       ///< decoding only
  50 } RLTable;
  51
  52 /**
  53  * @param static_store static uint8_t array[2][2*MAX_RUN + MAX_LEVEL + 3] which will hold
  54  *                     the level and run tables, if this is NULL av_malloc() will be used
  55  */
  56 int ff_rl_init(RLTable *rl, uint8_t static_store[2][2*MAX_RUN + MAX_LEVEL + 3]);
  57 void ff_rl_init_vlc(RLTable *rl);
  58
  59 /**
  60  * Free the contents of a dynamically allocated table.
  61  */
  62 void ff_rl_free(RLTable *rl);
  63
  64 #define INIT_VLC_RL(rl, static_size)\
  65 {\
  66     int q;\
  67     static RL_VLC_ELEM rl_vlc_table[32][static_size];\
  68     INIT_VLC_STATIC(&rl.vlc, 9, rl.n + 1,\
  69              &rl.table_vlc[0][1], 4, 2,\
  70              &rl.table_vlc[0][0], 4, 2, static_size);\
  71 \
  72     if(!rl.rl_vlc[0]){\
  73         for(q=0; q<32; q++)\
  74             rl.rl_vlc[q]= rl_vlc_table[q];\
  75 \
  76         ff_rl_init_vlc(&rl);\
  77     }\
  78 }
  79
  80 static inline int get_rl_index(const RLTable *rl, int last, int run, int level)
  81 {
  82     int index;
  83     index = rl->index_run[last][run];
  84     if (index >= rl->n)
  85         return rl->n;
  86     if (level > rl->max_level[last][run])
  87         return rl->n;
  88     return index + level - 1;
  89 }
  90
  91 #endif /* AVCODEC_RL_H */