ffmpeg/libavcodec/dirac_vlc.h

52 lines
1.8 KiB
C

/*
* Copyright (C) 2016 Open Broadcast Systems Ltd.
* Author 2016 Rostislav Pehlivanov <rpehlivanov@obe.tv>
*
* 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
*/
#ifndef AVCODEC_DIRAC_VLC_H
#define AVCODEC_DIRAC_VLC_H
#include "libavutil/avutil.h"
/* Can be 32 bits wide for some performance gain on some machines, but it will
* incorrectly decode very long coefficients (usually only 1 or 2 per frame) */
typedef uint64_t residual;
#define LUT_BITS 8
/* Exactly 64 bytes */
typedef struct DiracGolombLUT {
residual preamble, leftover;
int32_t ready[LUT_BITS];
int32_t preamble_bits, leftover_bits, ready_num;
int8_t need_s, sign;
} DiracGolombLUT;
av_cold int ff_dirac_golomb_reader_init(DiracGolombLUT **lut_ctx);
int ff_dirac_golomb_read_32bit(DiracGolombLUT *lut_ctx, const uint8_t *buf,
int bytes, uint8_t *dst, int coeffs);
int ff_dirac_golomb_read_16bit(DiracGolombLUT *lut_ctx, const uint8_t *buf,
int bytes, uint8_t *_dst, int coeffs);
av_cold void ff_dirac_golomb_reader_end(DiracGolombLUT **lut_ctx);
#endif /* AVCODEC_DIRAC_VLC_H */