mirror of https://github.com/FFmpeg/FFmpeg.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
51 lines
1.7 KiB
51 lines
1.7 KiB
/** |
|
* VP5 and VP6 compatible video decoder (arith decoder) |
|
* |
|
* Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org> |
|
* Copyright (C) 2010 Eli Friedman |
|
* |
|
* 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_X86_VP56_ARITH_H |
|
#define AVCODEC_X86_VP56_ARITH_H |
|
|
|
#if HAVE_INLINE_ASM && HAVE_FAST_CMOV |
|
#define vp56_rac_get_prob vp56_rac_get_prob |
|
static av_always_inline int vp56_rac_get_prob(VP56RangeCoder *c, uint8_t prob) |
|
{ |
|
unsigned int code_word = vp56_rac_renorm(c); |
|
unsigned int low = 1 + (((c->high - 1) * prob) >> 8); |
|
unsigned int low_shift = low << 16; |
|
int bit = 0; |
|
c->code_word = code_word; |
|
|
|
__asm__( |
|
"subl %4, %1 \n\t" |
|
"subl %3, %2 \n\t" |
|
"setae %b0 \n\t" |
|
"cmovb %4, %1 \n\t" |
|
"cmovb %5, %2 \n\t" |
|
: "+q"(bit), "+&r"(c->high), "+&r"(c->code_word) |
|
: "r"(low_shift), "r"(low), "r"(code_word) |
|
); |
|
|
|
return bit; |
|
} |
|
#endif |
|
|
|
#endif /* AVCODEC_X86_VP56_ARITH_H */
|
|
|