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dfe224f377
Based on the x86 branchless get_cabac asm. get_cabac_noinline() gets approximately 20% faster (no cycle counts available) compared to clang from Xcode 5.1 beta5. More than 6% faster overall. A part of the overall speedup might be explained by additional inlining of get_cabac().
55 lines
1.6 KiB
C
55 lines
1.6 KiB
C
/*
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* H.26L/H.264/AVC/JVT/14496-10/... encoder/decoder
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* Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
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*
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* This file is part of Libav.
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*
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* Libav is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* Libav is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with Libav; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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/**
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* @file
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* Context Adaptive Binary Arithmetic Coder.
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*/
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#ifndef AVCODEC_CABAC_H
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#define AVCODEC_CABAC_H
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#include <stdint.h>
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#include "put_bits.h"
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extern uint8_t ff_h264_cabac_tables[512 + 4*2*64 + 4*64 + 63];
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#define H264_NORM_SHIFT_OFFSET 0
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#define H264_LPS_RANGE_OFFSET 512
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#define H264_MLPS_STATE_OFFSET 1024
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#define H264_LAST_COEFF_FLAG_OFFSET_8x8_OFFSET 1280
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#define CABAC_BITS 16
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#define CABAC_MASK ((1<<CABAC_BITS)-1)
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typedef struct CABACContext{
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int low;
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int range;
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const uint8_t *bytestream_start;
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const uint8_t *bytestream;
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const uint8_t *bytestream_end;
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}CABACContext;
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void ff_init_cabac_decoder(CABACContext *c, const uint8_t *buf, int buf_size);
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void ff_init_cabac_states(void);
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#endif /* AVCODEC_CABAC_H */
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