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FFmpeg/libavcodec/cabac.h
Roland Scheidegger 14e9ffc1e4 h264: use one table instead of several for cabac functions
The reason is this is easier for PIC code (in particular on darwin...).
Keep the old names as pointers (static in cabac_functions.h so gcc
knows these are just immediate offsets) so the c code can nicely stay the same
(alternatively could use offsets directly in the functions needing the
tables). This should produce the same code as before with non-pic and better
code (confirmed) with pic.

The assembly uses the new table but still won't work for PIC case.

Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>
2012-04-28 08:26:12 -07:00

57 lines
1.7 KiB
C

/*
* H.26L/H.264/AVC/JVT/14496-10/... encoder/decoder
* Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* Context Adaptive Binary Arithmetic Coder.
*/
#ifndef AVCODEC_CABAC_H
#define AVCODEC_CABAC_H
#include <stdint.h>
#include "put_bits.h"
#define H264_NORM_SHIFT_OFFSET 0
#define H264_LPS_RANGE_OFFSET 512
#define H264_MLPS_STATE_OFFSET 1024
#define H264_LAST_COEFF_FLAG_OFFSET_8x8_OFFSET 1280
#define CABAC_BITS 16
#define CABAC_MASK ((1<<CABAC_BITS)-1)
typedef struct CABACContext{
int low;
int range;
int outstanding_count;
const uint8_t *bytestream_start;
const uint8_t *bytestream;
const uint8_t *bytestream_end;
PutBitContext pb;
}CABACContext;
void ff_init_cabac_encoder(CABACContext *c, uint8_t *buf, int buf_size);
void ff_init_cabac_decoder(CABACContext *c, const uint8_t *buf, int buf_size);
void ff_init_cabac_states(CABACContext *c);
#endif /* AVCODEC_CABAC_H */