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/*
* Copyright (c) 2000-2002 Fabrice Bellard
* Copyright (c) 2002-2004 Michael Niedermayer
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* rl header.
*/
#ifndef AVCODEC_RL_H
#define AVCODEC_RL_H
#include <stdint.h>
#include "vlc.h"
/* run length table */
#define MAX_RUN 64
#define MAX_LEVEL 64
/** RLTable. */
typedef struct RLTable {
int n; ///< number of entries of table_vlc minus 1
int last; ///< number of values for last = 0
const uint16_t (*table_vlc)[2];
const int8_t *table_run;
const int8_t *table_level;
uint8_t *index_run[2]; ///< encoding only
int8_t *max_level[2]; ///< encoding & decoding
int8_t *max_run[2]; ///< encoding & decoding
RL_VLC_ELEM *rl_vlc[32]; ///< decoding only
} RLTable;
/**
* Initialize max_level and index_run from table_run and table_level;
* this is equivalent to initializing RLTable.max_level[0] and
* RLTable.index_run[0] with ff_rl_init().
*/
void ff_rl_init_level_run(uint8_t max_level[MAX_LEVEL + 1],
uint8_t index_run[MAX_RUN + 1],
const uint8_t table_run[/* n */],
const uint8_t table_level[/* n*/], int n);
/**
* Initialize index_run, max_level and max_run from n, last, table_vlc,
* table_run and table_level.
* @param static_store static uint8_t array[2][2*MAX_RUN + MAX_LEVEL + 3]
* to hold the level and run tables.
* @note This function does not touch rl_vlc at all, hence there is no need
* to synchronize calls to ff_rl_init() and ff_rl_init_vlc() using the
* same RLTable.
*/
void ff_rl_init(RLTable *rl, uint8_t static_store[2][2*MAX_RUN + MAX_LEVEL + 3]);
/**
* Initialize rl_vlc from n, last, table_vlc, table_run and table_level.
* All rl_vlc pointers to be initialized must already point to a static
* buffer of `static_size` RL_VLC_ELEM elements; if a pointer is NULL,
* initializing further VLCs stops.
* @note This function does not touch what ff_rl_init() initializes at all,
* hence there is no need to synchronize calls to ff_rl_init() and
* ff_rl_init_vlc() using the same RLTable.
*/
void ff_rl_init_vlc(RLTable *rl, unsigned static_size);
#define VLC_INIT_RL(rl, static_size)\
{\
static RL_VLC_ELEM rl_vlc_table[32][static_size];\
\
for (int q = 0; q < 32; q++) \
rl.rl_vlc[q] = rl_vlc_table[q]; \
\
ff_rl_init_vlc(&rl, static_size); \
}
#define INIT_FIRST_VLC_RL(rl, static_size) \
do { \
static RL_VLC_ELEM rl_vlc_table[static_size]; \
\
rl.rl_vlc[0] = rl_vlc_table; \
ff_rl_init_vlc(&rl, static_size); \
} while (0)
static inline int get_rl_index(const RLTable *rl, int last, int run, int level)
{
int index;
index = rl->index_run[last][run];
if (index >= rl->n)
return rl->n;
if (level > rl->max_level[last][run])
return rl->n;
return index + level - 1;
}
#endif /* AVCODEC_RL_H */