1 /*****************************************************************************
2 * cabac.h: arithmetic coder
3 *****************************************************************************
4 * Copyright (C) 2003-2016 x264 project
6 * Authors: Loren Merritt <lorenm@u.washington.edu>
7 * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02111, USA.
23 * This program is also available under a commercial proprietary license.
24 * For more information, contact us at licensing@x264.com.
25 *****************************************************************************/
37 int i_queue; //stored with an offset of -8 for faster asm
38 int i_bytes_outstanding;
44 /* aligned for memcpy_aligned starting here */
45 ALIGNED_16( int f8_bits_encoded ); // only if using x264_cabac_size_decision()
50 /* for 16-byte alignment */
54 extern const uint8_t x264_cabac_transition[128][2];
55 extern const uint16_t x264_cabac_entropy[128];
57 /* init the contexts given i_slice_type, the quantif and the model */
58 void x264_cabac_context_init( x264_t *h, x264_cabac_t *cb, int i_slice_type, int i_qp, int i_model );
60 void x264_cabac_encode_init_core( x264_cabac_t *cb );
61 void x264_cabac_encode_init ( x264_cabac_t *cb, uint8_t *p_data, uint8_t *p_end );
62 void x264_cabac_encode_decision_c( x264_cabac_t *cb, int i_ctx, int b );
63 void x264_cabac_encode_decision_asm( x264_cabac_t *cb, int i_ctx, int b );
64 void x264_cabac_encode_bypass_c( x264_cabac_t *cb, int b );
65 void x264_cabac_encode_bypass_asm( x264_cabac_t *cb, int b );
66 void x264_cabac_encode_terminal_c( x264_cabac_t *cb );
67 void x264_cabac_encode_terminal_asm( x264_cabac_t *cb );
68 void x264_cabac_encode_ue_bypass( x264_cabac_t *cb, int exp_bits, int val );
69 void x264_cabac_encode_flush( x264_t *h, x264_cabac_t *cb );
72 #define x264_cabac_encode_decision x264_cabac_encode_decision_asm
73 #define x264_cabac_encode_bypass x264_cabac_encode_bypass_asm
74 #define x264_cabac_encode_terminal x264_cabac_encode_terminal_asm
75 #elif defined(ARCH_AARCH64)
76 #define x264_cabac_encode_decision x264_cabac_encode_decision_asm
77 #define x264_cabac_encode_bypass x264_cabac_encode_bypass_asm
78 #define x264_cabac_encode_terminal x264_cabac_encode_terminal_asm
80 #define x264_cabac_encode_decision x264_cabac_encode_decision_c
81 #define x264_cabac_encode_bypass x264_cabac_encode_bypass_c
82 #define x264_cabac_encode_terminal x264_cabac_encode_terminal_c
84 #define x264_cabac_encode_decision_noup x264_cabac_encode_decision
86 static ALWAYS_INLINE int x264_cabac_pos( x264_cabac_t *cb )
88 return (cb->p - cb->p_start + cb->i_bytes_outstanding) * 8 + cb->i_queue;
91 /* internal only. these don't write the bitstream, just calculate bit cost: */
93 static ALWAYS_INLINE void x264_cabac_size_decision( x264_cabac_t *cb, long i_ctx, long b )
95 int i_state = cb->state[i_ctx];
96 cb->state[i_ctx] = x264_cabac_transition[i_state][b];
97 cb->f8_bits_encoded += x264_cabac_entropy[i_state^b];
100 static ALWAYS_INLINE int x264_cabac_size_decision2( uint8_t *state, long b )
102 int i_state = *state;
103 *state = x264_cabac_transition[i_state][b];
104 return x264_cabac_entropy[i_state^b];
107 static ALWAYS_INLINE void x264_cabac_size_decision_noup( x264_cabac_t *cb, long i_ctx, long b )
109 int i_state = cb->state[i_ctx];
110 cb->f8_bits_encoded += x264_cabac_entropy[i_state^b];
113 static ALWAYS_INLINE int x264_cabac_size_decision_noup2( uint8_t *state, long b )
115 return x264_cabac_entropy[*state^b];