bitgolomb.h
资源名称:tcpmp.rar [点击查看]
上传用户:wstnjxml
上传日期:2014-04-03
资源大小:7248k
文件大小:3k
源码类别:
Windows CE
开发平台:
C/C++
- /*****************************************************************************
- *
- * This program is free software ; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program 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 General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
- * $Id: bitgolomb.h 292 2005-10-14 20:30:00Z picard $
- *
- * The Core Pocket Media Player
- * Copyright (c) 2004-2005 Gabor Kovacs
- *
- ****************************************************************************/
- #ifndef __BITGOLOMB_H
- #define __BITGOLOMB_H
- #define GL2(n) 12-n+1+12-n
- #define assertgolomb(p) //assert(p)
- static const uint8_t golomb_log2[64] =
- {
- GL2(0),
- GL2(1),
- GL2(2),GL2(2),
- GL2(3),GL2(3),GL2(3),GL2(3),
- GL2(4),GL2(4),GL2(4),GL2(4),GL2(4),GL2(4),GL2(4),GL2(4),
- GL2(5),GL2(5),GL2(5),GL2(5),GL2(5),GL2(5),GL2(5),GL2(5),
- GL2(5),GL2(5),GL2(5),GL2(5),GL2(5),GL2(5),GL2(5),GL2(5),
- GL2(6),GL2(6),GL2(6),GL2(6),GL2(6),GL2(6),GL2(6),GL2(6),
- GL2(6),GL2(6),GL2(6),GL2(6),GL2(6),GL2(6),GL2(6),GL2(6),
- GL2(6),GL2(6),GL2(6),GL2(6),GL2(6),GL2(6),GL2(6),GL2(6),
- GL2(6),GL2(6),GL2(6),GL2(6),GL2(6),GL2(6),GL2(6),GL2(6),
- };
- static void bitload(bitstream* p);
- // result: [0..8190]
- static NOINLINE int bitgolomb(bitstream* p)
- {
- int n,v;
- bitbegin_pos2(p);
- bitload_pos2(p);
- assertgolomb(bitshow_pos2(p,13)>0);
- if (bitshow_pos2(p,6))
- n = golomb_log2[bitshow_pos2(p,6)]-12;
- else
- n = golomb_log2[bitshow_pos2(p,12)];
- v = bitshow_pos2(p,n);
- bitflush_pos2(p,n);
- bitend_pos2(p);
- return --v;
- }
- // max: [2..7]
- // result: [0..(1<<max)-2]+1
- static INLINE int bitgolomb_max1(bitstream* p,int max)
- {
- int n;
- bitloadinline(p);
- assertgolomb(bitshow(p,max)>0);
- n = golomb_log2[bitshow(p,max-1)]-(13-max)*2;
- return bitget(p,n);
- }
- static NOINLINE int bitsgolomb(bitstream* p)
- {
- int n,v;
- bitbegin_pos2(p);
- bitload_pos2(p);
- assertgolomb(bitshow_pos2(p,13)>0);
- if (bitshow_pos2(p,6))
- n = golomb_log2[bitshow_pos2(p,6)]-12;
- else
- n = golomb_log2[bitshow_pos2(p,12)];
- v = bitshow_pos2(p,n);
- bitflush_pos2(p,n);
- bitend_pos2(p);
- if (v&1)
- v=-(v>>1);
- else
- v=(v>>1);
- return v;
- }
- #define DECLARE_BITSGOLOMB_LAGER
- static NOINLINE int bitsgolomb_large(bitstream* p)
- {
- int n;
- uint32_t v;
- bitloadinline(p);
- if (bitshow(p,13))
- return bitsgolomb(p);
- n = 14;
- bitflush(p,13);
- bitloadinline(p);
- while (!bitshow(p,1))
- {
- bitflush(p,1);
- ++n;
- }
- v = bitshowlarge(p,n);
- bitflush(p,n);
- if (v&1)
- return -(int)(v>>1);
- else
- return (v>>1);
- }
- #define DECLARE_BITGOLOMB_LAGER
- static NOINLINE int bitgolomb_large(bitstream* p)
- {
- int n;
- uint32_t v;
- bitloadinline(p);
- if (bitshow(p,13))
- return bitgolomb(p);
- n = 14;
- bitflush(p,13);
- bitloadinline(p);
- while (!bitshow(p,1))
- {
- bitflush(p,1);
- ++n;
- }
- v = bitshowlarge(p,n);
- bitflush(p,n);
- return --v;
- }
- #endif