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author | Michael Niedermayer <michaelni@gmx.at> | 2012-01-14 02:22:09 +0100 |
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committer | Michael Niedermayer <michaelni@gmx.at> | 2012-01-14 02:22:09 +0100 |
commit | e986a5d10d95b62cd85aaefc7d4da34699fbedeb (patch) | |
tree | 38dddca2b4582111bcf1bcb6be2d1c6193300f2d /libavcodec/cabac_functions.h | |
parent | 36397ea1c7e27ab850149cc61394c2baa26dd532 (diff) | |
parent | 68d6012c723bb520daac5336dcb046c0a5dd3826 (diff) | |
download | ffmpeg-e986a5d10d95b62cd85aaefc7d4da34699fbedeb.tar.gz |
Merge remote-tracking branch 'qatar/master'
* qatar/master:
FATE: add tests for targa
ARM: fix Thumb-mode simple_idct_arm
ARM: 4-byte align start of all asm functions
rgb2rgb: rgb12to15()
swscale-test: fix stack overread.
swscale: fix invalid conversions and memory problems.
cabac: split cabac.h into declarations and function definitions
cabac: Mark ff_h264_mps_state array as static, it is only used within cabac.c.
cabac: Remove ff_h264_lps_state array.
Conflicts:
libswscale/rgb2rgb.h
libswscale/swscale_unscaled.c
tests/fate/image.mak
Merged-by: Michael Niedermayer <michaelni@gmx.at>
Diffstat (limited to 'libavcodec/cabac_functions.h')
-rw-r--r-- | libavcodec/cabac_functions.h | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/libavcodec/cabac_functions.h b/libavcodec/cabac_functions.h new file mode 100644 index 0000000000..b150aabcc4 --- /dev/null +++ b/libavcodec/cabac_functions.h @@ -0,0 +1,160 @@ +/* + * 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 inline functions + */ + +#ifndef AVCODEC_CABAC_FUNCTIONS_H +#define AVCODEC_CABAC_FUNCTIONS_H + +#include <stdint.h> + +#include "cabac.h" +#include "config.h" + +#if ARCH_X86 +# include "x86/cabac.h" +#endif + +extern const uint8_t ff_h264_norm_shift[512]; +extern uint8_t ff_h264_mlps_state[4*64]; +extern uint8_t ff_h264_lps_range[4*2*64]; ///< rangeTabLPS + +static void refill(CABACContext *c){ +#if CABAC_BITS == 16 + c->low+= (c->bytestream[0]<<9) + (c->bytestream[1]<<1); +#else + c->low+= c->bytestream[0]<<1; +#endif + c->low -= CABAC_MASK; + c->bytestream+= CABAC_BITS/8; +} + +static inline void renorm_cabac_decoder_once(CABACContext *c){ + int shift= (uint32_t)(c->range - 0x100)>>31; + c->range<<= shift; + c->low <<= shift; + if(!(c->low & CABAC_MASK)) + refill(c); +} + +#ifndef get_cabac_inline +static void refill2(CABACContext *c){ + int i, x; + + x= c->low ^ (c->low-1); + i= 7 - ff_h264_norm_shift[x>>(CABAC_BITS-1)]; + + x= -CABAC_MASK; + +#if CABAC_BITS == 16 + x+= (c->bytestream[0]<<9) + (c->bytestream[1]<<1); +#else + x+= c->bytestream[0]<<1; +#endif + + c->low += x<<i; + c->bytestream+= CABAC_BITS/8; +} + +static av_always_inline int get_cabac_inline(CABACContext *c, uint8_t * const state){ + int s = *state; + int RangeLPS= ff_h264_lps_range[2*(c->range&0xC0) + s]; + int bit, lps_mask; + + c->range -= RangeLPS; + lps_mask= ((c->range<<(CABAC_BITS+1)) - c->low)>>31; + + c->low -= (c->range<<(CABAC_BITS+1)) & lps_mask; + c->range += (RangeLPS - c->range) & lps_mask; + + s^=lps_mask; + *state= (ff_h264_mlps_state+128)[s]; + bit= s&1; + + lps_mask= ff_h264_norm_shift[c->range]; + c->range<<= lps_mask; + c->low <<= lps_mask; + if(!(c->low & CABAC_MASK)) + refill2(c); + return bit; +} +#endif + +static int av_noinline av_unused get_cabac_noinline(CABACContext *c, uint8_t * const state){ + return get_cabac_inline(c,state); +} + +static int av_unused get_cabac(CABACContext *c, uint8_t * const state){ + return get_cabac_inline(c,state); +} + +static int av_unused get_cabac_bypass(CABACContext *c){ + int range; + c->low += c->low; + + if(!(c->low & CABAC_MASK)) + refill(c); + + range= c->range<<(CABAC_BITS+1); + if(c->low < range){ + return 0; + }else{ + c->low -= range; + return 1; + } +} + + +#ifndef get_cabac_bypass_sign +static av_always_inline int get_cabac_bypass_sign(CABACContext *c, int val){ + int range, mask; + c->low += c->low; + + if(!(c->low & CABAC_MASK)) + refill(c); + + range= c->range<<(CABAC_BITS+1); + c->low -= range; + mask= c->low >> 31; + range &= mask; + c->low += range; + return (val^mask)-mask; +} +#endif + +/** + * + * @return the number of bytes read or 0 if no end + */ +static int av_unused get_cabac_terminate(CABACContext *c){ + c->range -= 2; + if(c->low < c->range<<(CABAC_BITS+1)){ + renorm_cabac_decoder_once(c); + return 0; + }else{ + return c->bytestream - c->bytestream_start; + } +} + +#endif /* AVCODEC_CABAC_FUNCTIONS_H */ |