1 /*****************************************************************************
2 * cabac.h: h264 encoder library
3 *****************************************************************************
4 * Copyright (C) 2003 Laurent Aimar
5 * $Id: cabac.h,v 1.1 2004/06/03 19:27:06 fenrir Exp $
7 * Authors: Laurent Aimar <fenrir@via.ecp.fr>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
22 *****************************************************************************/
30 DECLARE_ALIGNED_16( uint8_t state[460] );
32 int f8_bits_encoded; // only if using x264_cabac_size_decision()
40 int i_bytes_outstanding;
48 extern const uint8_t x264_cabac_transition[128][2];
49 extern const uint16_t x264_cabac_entropy[128][2];
51 /* init the contexts given i_slice_type, the quantif and the model */
52 void x264_cabac_context_init( x264_cabac_t *cb, int i_slice_type, int i_qp, int i_model );
55 void x264_cabac_encode_init ( x264_cabac_t *cb, uint8_t *p_data, uint8_t *p_end );
56 void x264_cabac_encode_decision( x264_cabac_t *cb, int i_ctx, int b );
57 void x264_cabac_encode_bypass( x264_cabac_t *cb, int b );
58 void x264_cabac_encode_terminal( x264_cabac_t *cb );
59 void x264_cabac_encode_flush( x264_t *h, x264_cabac_t *cb );
61 static inline int x264_cabac_pos( x264_cabac_t *cb )
63 return (cb->p - cb->p_start + cb->i_bytes_outstanding) * 8 + cb->i_queue;
66 /* internal only. these don't write the bitstream, just calculate bit cost: */
68 static inline void x264_cabac_size_decision( x264_cabac_t *cb, long i_ctx, long b )
70 int i_state = cb->state[i_ctx];
71 cb->state[i_ctx] = x264_cabac_transition[i_state][b];
72 cb->f8_bits_encoded += x264_cabac_entropy[i_state][b];
75 static inline int x264_cabac_size_decision2( uint8_t *state, long b )
78 *state = x264_cabac_transition[i_state][b];
79 return x264_cabac_entropy[i_state][b];
82 static inline int x264_cabac_size_decision_noup( uint8_t *state, long b )
84 return x264_cabac_entropy[*state][b];