?? bs.h.svn-base
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/***************************************************************************** * bs.h : ***************************************************************************** * Copyright (C) 2003 Laurent Aimar * $Id: bs.h,v 1.1 2004/06/03 19:27:06 fenrir Exp $ * * Authors: Laurent Aimar <fenrir@via.ecp.fr> * * 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, USA. *****************************************************************************/#ifdef _BS_H#warning FIXME Multiple inclusion of bs.h#else#define _BS_Htypedef struct bs_s{ uint8_t *p_start; uint8_t *p; uint8_t *p_end; int i_left; /* i_count number of available bits */} bs_t;static inline void bs_init( bs_t *s, void *p_data, int i_data ){ s->p_start = p_data; s->p = p_data; s->p_end = s->p + i_data; s->i_left = 8;}static inline int bs_pos( bs_t *s ){ return( 8 * ( s->p - s->p_start ) + 8 - s->i_left );}static inline int bs_eof( bs_t *s ){ return( s->p >= s->p_end ? 1: 0 );}static inline uint32_t bs_read( bs_t *s, int i_count ){ static uint32_t i_mask[33] ={0x00, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f, 0xff, 0x1ff, 0x3ff, 0x7ff, 0xfff, 0x1fff, 0x3fff, 0x7fff, 0xffff, 0x1ffff, 0x3ffff, 0x7ffff, 0xfffff, 0x1fffff, 0x3fffff, 0x7fffff, 0xffffff, 0x1ffffff, 0x3ffffff, 0x7ffffff, 0xfffffff, 0x1fffffff,0x3fffffff,0x7fffffff,0xffffffff}; int i_shr; uint32_t i_result = 0; while( i_count > 0 ) { if( s->p >= s->p_end ) { break; } if( ( i_shr = s->i_left - i_count ) >= 0 ) { /* more in the buffer than requested */ i_result |= ( *s->p >> i_shr )&i_mask[i_count]; s->i_left -= i_count; if( s->i_left == 0 ) { s->p++; s->i_left = 8; } return( i_result ); } else { /* less in the buffer than requested */ i_result |= (*s->p&i_mask[s->i_left]) << -i_shr; i_count -= s->i_left; s->p++; s->i_left = 8; } } return( i_result );}#if 0/* Only > i386 */static uint32_t bswap32( uint32_t x ){ asm( "bswap %0": "=r" (x):"0" (x)); return x;}/* work only for i_count <= 32 - 7 */static inline uint32_t bs_read( bs_t *s, int i_count ){ if( s->p < s->p_end && i_count > 0 ) {#if 0 uint32_t i_cache = ((s->p[0] << 24)+(s->p[1] << 16)+(s->p[2] << 8)+s->p[3]) << (8-s->i_left);#else uint32_t i_cache = bswap32( *((uint32_t*)s->p) ) << (8-s->i_left);#endif uint32_t i_ret = i_cache >> ( 32 - i_count); s->i_left -= i_count;#if 0 if( s->i_left <= 0 ) { int i_skip = (8-s->i_left) >> 3; s->p += i_skip; s->i_left += i_skip << 3; }#else while( s->i_left <= 0 ) { s->p++; s->i_left += 8; }#endif return i_ret; } return 0;}#endifstatic inline uint32_t bs_read1( bs_t *s ){ if( s->p < s->p_end ) { unsigned int i_result; s->i_left--; i_result = ( *s->p >> s->i_left )&0x01; if( s->i_left == 0 ) { s->p++; s->i_left = 8; } return i_result; } return 0;}static inline uint32_t bs_show( bs_t *s, int i_count ){#if 0 bs_t s_tmp = *s; return bs_read( &s_tmp, i_count );#else if( s->p < s->p_end && i_count > 0 ) { uint32_t i_cache = ((s->p[0] << 24)+(s->p[1] << 16)+(s->p[2] << 8)+s->p[3]) << (8-s->i_left); return( i_cache >> ( 32 - i_count) ); } return 0;#endif}/* TODO optimize */static inline void bs_skip( bs_t *s, int i_count ){ s->i_left -= i_count; while( s->i_left <= 0 ) { s->p++; s->i_left += 8; }}static inline int bs_read_ue( bs_t *s ){ int i = 0; while( bs_read1( s ) == 0 && s->p < s->p_end && i < 32 ) { i++; } return( ( 1 << i) - 1 + bs_read( s, i ) );}static inline int bs_read_se( bs_t *s ){ int val = bs_read_ue( s ); return val&0x01 ? (val+1)/2 : -(val/2);}static inline int bs_read_te( bs_t *s, int x ){ if( x == 1 ) { return 1 - bs_read1( s ); } else if( x > 1 ) { return bs_read_ue( s ); } return 0;}/* TODO optimize (write x bits at once) */static inline void bs_write( bs_t *s, int i_count, uint32_t i_bits ){ while( i_count > 0 ) { if( s->p >= s->p_end ) { break; } i_count--; if( ( i_bits >> i_count )&0x01 ) { *s->p |= 1 << ( s->i_left - 1 ); } else { *s->p &= ~( 1 << ( s->i_left - 1 ) ); } s->i_left--; if( s->i_left == 0 ) { s->p++; s->i_left = 8; } }}static inline void bs_write1( bs_t *s, uint32_t i_bits ){ if( s->p < s->p_end ) { s->i_left--; if( i_bits&0x01 ) { *s->p |= 1 << s->i_left; } else { *s->p &= ~( 1 << s->i_left ); } if( s->i_left == 0 ) { s->p++; s->i_left = 8; } }}static inline void bs_align( bs_t *s ){ if( s->i_left != 8 ) { s->i_left = 8; s->p++; }}static inline void bs_align_0( bs_t *s ){ if( s->i_left != 8 ) { bs_write( s, s->i_left, 0 ); }}static inline void bs_align_1( bs_t *s ){ if( s->i_left != 8 ) { bs_write( s, s->i_left, ~0 ); }}/* golomb functions */static inline void bs_write_ue( bs_t *s, unsigned int val ){ int i_size = 0; static const int i_size0_255[256] = { 1,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5, 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6, 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8 }; if( val == 0 ) { bs_write( s, 1, 1 ); } else { unsigned int tmp = ++val; if( tmp >= 0x00010000 ) { i_size += 16; tmp >>= 16; } if( tmp >= 0x100 ) { i_size += 8; tmp >>= 8; } i_size += i_size0_255[tmp]; bs_write( s, 2 * i_size - 1, val ); }}static inline void bs_write_se( bs_t *s, int val ){ bs_write_ue( s, val <= 0 ? -val * 2 : val * 2 - 1);}static inline void bs_write_te( bs_t *s, int x, int val ){ if( x == 1 ) { bs_write( s, 1, ~val ); } else if( x > 1 ) { bs_write_ue( s, val ); }}static inline void bs_rbsp_trailing( bs_t *s ){ bs_write( s, 1, 1 ); if( s->i_left != 8 ) { bs_write( s, s->i_left, 0x00 ); }}static inline int bs_size_ue( unsigned int val ){ static const int i_size0_254[255] = { 1, 3, 3, 5, 5, 5, 5, 7, 7, 7, 7, 7, 7, 7, 7, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11, 11,11,11,11,11,11,11,11,11,13,13,13,13,13,13,13,13,13,13,13,13,13,13, 13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13, 13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13, 13,13,13,13,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15, 15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15, 15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15, 15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15, 15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15, 15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15 }; if( val < 255 ) { return i_size0_254[val]; } else { int i_size = 0; val++; if( val >= 0x10000 ) { i_size += 32; val = (val >> 16) - 1; } if( val >= 0x100 ) { i_size += 16; val = (val >> 8) - 1; } return i_size0_254[val] + i_size; }}static inline int bs_size_se( int val ){ return bs_size_ue( val <= 0 ? -val * 2 : val * 2 - 1);}static inline int bs_size_te( int x, int val ){ if( x == 1 ) { return 1; } else if( x > 1 ) { return bs_size_ue( val ); } return 0;}#endif
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