1 |
|
|
/* |
2 |
|
|
* H.26L/H.264/AVC/JVT/14496-10/... encoder/decoder |
3 |
|
|
* Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at> |
4 |
|
|
* |
5 |
|
|
* This file is part of FFmpeg. |
6 |
|
|
* |
7 |
|
|
* FFmpeg is free software; you can redistribute it and/or |
8 |
|
|
* modify it under the terms of the GNU Lesser General Public |
9 |
|
|
* License as published by the Free Software Foundation; either |
10 |
|
|
* version 2.1 of the License, or (at your option) any later version. |
11 |
|
|
* |
12 |
|
|
* FFmpeg is distributed in the hope that it will be useful, |
13 |
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of |
14 |
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
15 |
|
|
* Lesser General Public License for more details. |
16 |
|
|
* |
17 |
|
|
* You should have received a copy of the GNU Lesser General Public |
18 |
|
|
* License along with FFmpeg; if not, write to the Free Software |
19 |
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
20 |
|
|
*/ |
21 |
|
|
|
22 |
|
|
/** |
23 |
|
|
* @file |
24 |
|
|
* Context Adaptive Binary Arithmetic Coder inline functions |
25 |
|
|
*/ |
26 |
|
|
|
27 |
|
|
#ifndef AVCODEC_CABAC_FUNCTIONS_H |
28 |
|
|
#define AVCODEC_CABAC_FUNCTIONS_H |
29 |
|
|
|
30 |
|
|
#include <stdint.h> |
31 |
|
|
|
32 |
|
|
#include "cabac.h" |
33 |
|
|
#include "config.h" |
34 |
|
|
|
35 |
|
|
#ifndef UNCHECKED_BITSTREAM_READER |
36 |
|
|
#define UNCHECKED_BITSTREAM_READER !CONFIG_SAFE_BITSTREAM_READER |
37 |
|
|
#endif |
38 |
|
|
|
39 |
|
|
#if ARCH_AARCH64 |
40 |
|
|
# include "aarch64/cabac.h" |
41 |
|
|
#endif |
42 |
|
|
#if ARCH_ARM |
43 |
|
|
# include "arm/cabac.h" |
44 |
|
|
#endif |
45 |
|
|
#if ARCH_X86 |
46 |
|
|
# include "x86/cabac.h" |
47 |
|
|
#endif |
48 |
|
|
#if ARCH_MIPS |
49 |
|
|
# include "mips/cabac.h" |
50 |
|
|
#endif |
51 |
|
|
|
52 |
|
|
static const uint8_t * const ff_h264_norm_shift = ff_h264_cabac_tables + H264_NORM_SHIFT_OFFSET; |
53 |
|
|
static const uint8_t * const ff_h264_lps_range = ff_h264_cabac_tables + H264_LPS_RANGE_OFFSET; |
54 |
|
|
static const uint8_t * const ff_h264_mlps_state = ff_h264_cabac_tables + H264_MLPS_STATE_OFFSET; |
55 |
|
|
static const uint8_t * const ff_h264_last_coeff_flag_offset_8x8 = ff_h264_cabac_tables + H264_LAST_COEFF_FLAG_OFFSET_8x8_OFFSET; |
56 |
|
|
|
57 |
|
|
#if !defined(get_cabac_bypass) || !defined(get_cabac_terminate) |
58 |
|
22273 |
static void refill(CABACContext *c){ |
59 |
|
|
#if CABAC_BITS == 16 |
60 |
|
22273 |
c->low+= (c->bytestream[0]<<9) + (c->bytestream[1]<<1); |
61 |
|
|
#else |
62 |
|
|
c->low+= c->bytestream[0]<<1; |
63 |
|
|
#endif |
64 |
|
22273 |
c->low -= CABAC_MASK; |
65 |
|
|
#if !UNCHECKED_BITSTREAM_READER |
66 |
✓✓ |
20203 |
if (c->bytestream < c->bytestream_end) |
67 |
|
|
#endif |
68 |
|
22228 |
c->bytestream += CABAC_BITS / 8; |
69 |
|
22273 |
} |
70 |
|
|
#endif |
71 |
|
|
|
72 |
|
|
#ifndef get_cabac_terminate |
73 |
|
9832535 |
static inline void renorm_cabac_decoder_once(CABACContext *c){ |
74 |
|
9832535 |
int shift= (uint32_t)(c->range - 0x100)>>31; |
75 |
|
9832535 |
c->range<<= shift; |
76 |
|
9832535 |
c->low <<= shift; |
77 |
✓✓ |
9832535 |
if(!(c->low & CABAC_MASK)) |
78 |
|
22273 |
refill(c); |
79 |
|
9832535 |
} |
80 |
|
|
#endif |
81 |
|
|
|
82 |
|
|
#ifndef get_cabac_inline |
83 |
|
|
static void refill2(CABACContext *c){ |
84 |
|
|
int i; |
85 |
|
|
unsigned x; |
86 |
|
|
#if !HAVE_FAST_CLZ |
87 |
|
|
x= c->low ^ (c->low-1); |
88 |
|
|
i= 7 - ff_h264_norm_shift[x>>(CABAC_BITS-1)]; |
89 |
|
|
#else |
90 |
|
|
i = ff_ctz(c->low) - CABAC_BITS; |
91 |
|
|
#endif |
92 |
|
|
|
93 |
|
|
x= -CABAC_MASK; |
94 |
|
|
|
95 |
|
|
#if CABAC_BITS == 16 |
96 |
|
|
x+= (c->bytestream[0]<<9) + (c->bytestream[1]<<1); |
97 |
|
|
#else |
98 |
|
|
x+= c->bytestream[0]<<1; |
99 |
|
|
#endif |
100 |
|
|
|
101 |
|
|
c->low += x<<i; |
102 |
|
|
#if !UNCHECKED_BITSTREAM_READER |
103 |
|
|
if (c->bytestream < c->bytestream_end) |
104 |
|
|
#endif |
105 |
|
|
c->bytestream += CABAC_BITS/8; |
106 |
|
|
} |
107 |
|
|
#endif |
108 |
|
|
|
109 |
|
|
#ifndef get_cabac_inline |
110 |
|
|
static av_always_inline int get_cabac_inline(CABACContext *c, uint8_t * const state){ |
111 |
|
|
int s = *state; |
112 |
|
|
int RangeLPS= ff_h264_lps_range[2*(c->range&0xC0) + s]; |
113 |
|
|
int bit, lps_mask; |
114 |
|
|
|
115 |
|
|
c->range -= RangeLPS; |
116 |
|
|
lps_mask= ((c->range<<(CABAC_BITS+1)) - c->low)>>31; |
117 |
|
|
|
118 |
|
|
c->low -= (c->range<<(CABAC_BITS+1)) & lps_mask; |
119 |
|
|
c->range += (RangeLPS - c->range) & lps_mask; |
120 |
|
|
|
121 |
|
|
s^=lps_mask; |
122 |
|
|
*state= (ff_h264_mlps_state+128)[s]; |
123 |
|
|
bit= s&1; |
124 |
|
|
|
125 |
|
|
lps_mask= ff_h264_norm_shift[c->range]; |
126 |
|
|
c->range<<= lps_mask; |
127 |
|
|
c->low <<= lps_mask; |
128 |
|
|
if(!(c->low & CABAC_MASK)) |
129 |
|
|
refill2(c); |
130 |
|
|
return bit; |
131 |
|
|
} |
132 |
|
|
#endif |
133 |
|
|
|
134 |
|
80278402 |
static int av_noinline av_unused get_cabac_noinline(CABACContext *c, uint8_t * const state){ |
135 |
|
80278402 |
return get_cabac_inline(c,state); |
136 |
|
|
} |
137 |
|
|
|
138 |
|
989566016 |
static int av_unused get_cabac(CABACContext *c, uint8_t * const state){ |
139 |
|
989566016 |
return get_cabac_inline(c,state); |
140 |
|
|
} |
141 |
|
|
|
142 |
|
|
#ifndef get_cabac_bypass |
143 |
|
|
static int av_unused get_cabac_bypass(CABACContext *c){ |
144 |
|
|
int range; |
145 |
|
|
c->low += c->low; |
146 |
|
|
|
147 |
|
|
if(!(c->low & CABAC_MASK)) |
148 |
|
|
refill(c); |
149 |
|
|
|
150 |
|
|
range= c->range<<(CABAC_BITS+1); |
151 |
|
|
if(c->low < range){ |
152 |
|
|
return 0; |
153 |
|
|
}else{ |
154 |
|
|
c->low -= range; |
155 |
|
|
return 1; |
156 |
|
|
} |
157 |
|
|
} |
158 |
|
|
#endif |
159 |
|
|
|
160 |
|
|
#ifndef get_cabac_bypass_sign |
161 |
|
|
static av_always_inline int get_cabac_bypass_sign(CABACContext *c, int val){ |
162 |
|
|
int range, mask; |
163 |
|
|
c->low += c->low; |
164 |
|
|
|
165 |
|
|
if(!(c->low & CABAC_MASK)) |
166 |
|
|
refill(c); |
167 |
|
|
|
168 |
|
|
range= c->range<<(CABAC_BITS+1); |
169 |
|
|
c->low -= range; |
170 |
|
|
mask= c->low >> 31; |
171 |
|
|
range &= mask; |
172 |
|
|
c->low += range; |
173 |
|
|
return (val^mask)-mask; |
174 |
|
|
} |
175 |
|
|
#endif |
176 |
|
|
|
177 |
|
|
/** |
178 |
|
|
* @return the number of bytes read or 0 if no end |
179 |
|
|
*/ |
180 |
|
|
#ifndef get_cabac_terminate |
181 |
|
9899166 |
static int av_unused get_cabac_terminate(CABACContext *c){ |
182 |
|
9899166 |
c->range -= 2; |
183 |
✓✓ |
9899166 |
if(c->low < c->range<<(CABAC_BITS+1)){ |
184 |
|
9832535 |
renorm_cabac_decoder_once(c); |
185 |
|
9832535 |
return 0; |
186 |
|
|
}else{ |
187 |
|
66631 |
return c->bytestream - c->bytestream_start; |
188 |
|
|
} |
189 |
|
|
} |
190 |
|
|
#endif |
191 |
|
|
|
192 |
|
|
/** |
193 |
|
|
* Skip @p n bytes and reset the decoder. |
194 |
|
|
* @return the address of the first skipped byte or NULL if there's less than @p n bytes left |
195 |
|
|
*/ |
196 |
|
|
#ifndef skip_bytes |
197 |
|
20037 |
static av_unused const uint8_t* skip_bytes(CABACContext *c, int n) { |
198 |
|
20037 |
const uint8_t *ptr = c->bytestream; |
199 |
|
|
|
200 |
✓✓ |
20037 |
if (c->low & 0x1) |
201 |
|
1145 |
ptr--; |
202 |
|
|
#if CABAC_BITS == 16 |
203 |
✓✓ |
20037 |
if (c->low & 0x1FF) |
204 |
|
10906 |
ptr--; |
205 |
|
|
#endif |
206 |
✗✓ |
20037 |
if ((int) (c->bytestream_end - ptr) < n) |
207 |
|
|
return NULL; |
208 |
✗✓ |
20037 |
if (ff_init_cabac_decoder(c, ptr + n, c->bytestream_end - ptr - n) < 0) |
209 |
|
|
return NULL; |
210 |
|
|
|
211 |
|
20037 |
return ptr; |
212 |
|
|
} |
213 |
|
|
#endif |
214 |
|
|
|
215 |
|
|
#endif /* AVCODEC_CABAC_FUNCTIONS_H */ |