/*****************************************************************************
* cabac.c: h264 encoder library
*****************************************************************************
- * Copyright (C) 2003 Laurent Aimar
- * $Id: cabac.c,v 1.1 2004/06/03 19:27:06 fenrir Exp $
+ * Copyright (C) 2003-2008 x264 project
*
* Authors: Laurent Aimar <fenrir@via.ecp.fr>
+ * Loren Merritt <lorenm@u.washington.edu>
*
* 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
*
* 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.
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111, USA.
*****************************************************************************/
#include "common.h"
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
};
-static const uint8_t x264_cabac_probability[128] =
-{
- FIX8(0.9812), FIX8(0.9802), FIX8(0.9792), FIX8(0.9781),
- FIX8(0.9769), FIX8(0.9757), FIX8(0.9744), FIX8(0.9730),
- FIX8(0.9716), FIX8(0.9700), FIX8(0.9684), FIX8(0.9667),
- FIX8(0.9650), FIX8(0.9631), FIX8(0.9611), FIX8(0.9590),
- FIX8(0.9568), FIX8(0.9545), FIX8(0.9521), FIX8(0.9495),
- FIX8(0.9468), FIX8(0.9440), FIX8(0.9410), FIX8(0.9378),
- FIX8(0.9345), FIX8(0.9310), FIX8(0.9273), FIX8(0.9234),
- FIX8(0.9193), FIX8(0.9150), FIX8(0.9105), FIX8(0.9057),
- FIX8(0.9006), FIX8(0.8953), FIX8(0.8897), FIX8(0.8838),
- FIX8(0.8776), FIX8(0.8710), FIX8(0.8641), FIX8(0.8569),
- FIX8(0.8492), FIX8(0.8411), FIX8(0.8326), FIX8(0.8237),
- FIX8(0.8143), FIX8(0.8043), FIX8(0.7938), FIX8(0.7828),
- FIX8(0.7712), FIX8(0.7590), FIX8(0.7461), FIX8(0.7325),
- FIX8(0.7182), FIX8(0.7031), FIX8(0.6872), FIX8(0.6705),
- FIX8(0.6528), FIX8(0.6343), FIX8(0.6147), FIX8(0.5941),
- FIX8(0.5724), FIX8(0.5495), FIX8(0.5254), FIX8(0.5000),
- FIX8(0.5000), FIX8(0.4746), FIX8(0.4505), FIX8(0.4276),
- FIX8(0.4059), FIX8(0.3853), FIX8(0.3657), FIX8(0.3472),
- FIX8(0.3295), FIX8(0.3128), FIX8(0.2969), FIX8(0.2818),
- FIX8(0.2675), FIX8(0.2539), FIX8(0.2410), FIX8(0.2288),
- FIX8(0.2172), FIX8(0.2062), FIX8(0.1957), FIX8(0.1857),
- FIX8(0.1763), FIX8(0.1674), FIX8(0.1589), FIX8(0.1508),
- FIX8(0.1431), FIX8(0.1359), FIX8(0.1290), FIX8(0.1224),
- FIX8(0.1162), FIX8(0.1103), FIX8(0.1047), FIX8(0.0994),
- FIX8(0.0943), FIX8(0.0895), FIX8(0.0850), FIX8(0.0807),
- FIX8(0.0766), FIX8(0.0727), FIX8(0.0690), FIX8(0.0655),
- FIX8(0.0622), FIX8(0.0590), FIX8(0.0560), FIX8(0.0532),
- FIX8(0.0505), FIX8(0.0479), FIX8(0.0455), FIX8(0.0432),
- FIX8(0.0410), FIX8(0.0389), FIX8(0.0369), FIX8(0.0350),
- FIX8(0.0333), FIX8(0.0316), FIX8(0.0300), FIX8(0.0284),
- FIX8(0.0270), FIX8(0.0256), FIX8(0.0243), FIX8(0.0231),
- FIX8(0.0219), FIX8(0.0208), FIX8(0.0198), FIX8(0.0187)
-};
/* -ln2(probability) */
#define F(a,b) {FIX8(a),FIX8(b)}
const uint16_t x264_cabac_entropy[128][2] =
void x264_cabac_context_init( x264_cabac_t *cb, int i_slice_type, int i_qp, int i_model )
{
const int8_t (*cabac_context_init)[460][2];
- int i;
if( i_slice_type == SLICE_TYPE_I )
- {
cabac_context_init = &x264_cabac_context_init_I;
- }
else
- {
cabac_context_init = &x264_cabac_context_init_PB[i_model];
- }
- for( i = 0; i < 460; i++ )
- {
+ for( int i = 0; i < 460; i++ )
cb->state[i] = x264_clip3( (((*cabac_context_init)[i][0] * i_qp) >> 4) + (*cabac_context_init)[i][1], 1, 126 );
- }
}
void x264_cabac_encode_init( x264_cabac_t *cb, uint8_t *p_data, uint8_t *p_end )
cb->i_queue -= 8;
if( (out & 0xff) == 0xff )
- {
cb->i_bytes_outstanding++;
- }
else
{
int carry = out >> 8;
x264_cabac_putbyte( cb );
}
+/* Making custom versions of this function, even in asm, for the cases where
+ * b is known to be 0 or 1, proved to be somewhat useful on x86_32 with GCC 3.4
+ * but nearly useless with GCC 4.3 and worse than useless on x86_64. */
void x264_cabac_encode_decision_c( x264_cabac_t *cb, int i_ctx, int b )
{
int i_state = cb->state[i_ctx];
- int i_range_lps = x264_cabac_range_lps[i_state][(cb->i_range>>6)&0x03];
+ int i_range_lps = x264_cabac_range_lps[i_state][(cb->i_range>>6)-4];
cb->i_range -= i_range_lps;
if( b != (i_state >> 6) )
{
void x264_cabac_encode_ue_bypass( x264_cabac_t *cb, int exp_bits, int val )
{
int k, i;
- uint32_t x;
for( k = exp_bits; val >= (1<<k); k++ )
val -= 1<<k;
- x = (((1<<(k-exp_bits))-1)<<(k+1))+val;
+ uint32_t x = (((1<<(k-exp_bits))-1)<<(k+1))+val;
k = 2*k+1-exp_bits;
i = ((k-1)&7)+1;
do {