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mathops.h
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1 /*
2  * simple math operations
3  * Copyright (c) 2001, 2002 Fabrice Bellard
4  * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at> et al
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 #ifndef AVCODEC_MATHOPS_H
23 #define AVCODEC_MATHOPS_H
24 
25 #include <stdint.h>
26 
27 #include "libavutil/common.h"
28 #include "libavutil/reverse.h"
29 #include "config.h"
30 
31 #define MAX_NEG_CROP 1024
32 
33 extern const uint32_t ff_inverse[257];
34 extern const uint8_t ff_sqrt_tab[256];
35 extern const uint8_t ff_crop_tab[256 + 2 * MAX_NEG_CROP];
36 extern const uint8_t ff_zigzag_direct[64];
37 extern const uint8_t ff_zigzag_scan[16+1];
38 
39 #if ARCH_ARM
40 # include "arm/mathops.h"
41 #elif ARCH_AVR32
42 # include "avr32/mathops.h"
43 #elif ARCH_MIPS
44 # include "mips/mathops.h"
45 #elif ARCH_PPC
46 # include "ppc/mathops.h"
47 #elif ARCH_X86
48 # include "x86/mathops.h"
49 #endif
50 
51 /* generic implementation */
52 
53 #ifndef MUL64
54 # define MUL64(a,b) ((int64_t)(a) * (int64_t)(b))
55 #endif
56 
57 #ifndef MULL
58 # define MULL(a,b,s) (MUL64(a, b) >> (s))
59 #endif
60 
61 #ifndef MULH
62 static av_always_inline int MULH(int a, int b){
63  return MUL64(a, b) >> 32;
64 }
65 #endif
66 
67 #ifndef UMULH
68 static av_always_inline unsigned UMULH(unsigned a, unsigned b){
69  return ((uint64_t)(a) * (uint64_t)(b))>>32;
70 }
71 #endif
72 
73 #ifndef MAC64
74 # define MAC64(d, a, b) ((d) += MUL64(a, b))
75 #endif
76 
77 #ifndef MLS64
78 # define MLS64(d, a, b) ((d) -= MUL64(a, b))
79 #endif
80 
81 /* signed 16x16 -> 32 multiply add accumulate */
82 #ifndef MAC16
83 # define MAC16(rt, ra, rb) rt += (ra) * (rb)
84 #endif
85 
86 /* signed 16x16 -> 32 multiply */
87 #ifndef MUL16
88 # define MUL16(ra, rb) ((ra) * (rb))
89 #endif
90 
91 #ifndef MLS16
92 # define MLS16(rt, ra, rb) ((rt) -= (ra) * (rb))
93 #endif
94 
95 /* median of 3 */
96 #ifndef mid_pred
97 #define mid_pred mid_pred
98 static inline av_const int mid_pred(int a, int b, int c)
99 {
100  if(a>b){
101  if(c>b){
102  if(c>a) b=a;
103  else b=c;
104  }
105  }else{
106  if(b>c){
107  if(c>a) b=c;
108  else b=a;
109  }
110  }
111  return b;
112 }
113 #endif
114 
115 #ifndef median4
116 #define median4 median4
117 static inline av_const int median4(int a, int b, int c, int d)
118 {
119  if (a < b) {
120  if (c < d) return (FFMIN(b, d) + FFMAX(a, c)) / 2;
121  else return (FFMIN(b, c) + FFMAX(a, d)) / 2;
122  } else {
123  if (c < d) return (FFMIN(a, d) + FFMAX(b, c)) / 2;
124  else return (FFMIN(a, c) + FFMAX(b, d)) / 2;
125  }
126 }
127 #endif
128 
129 #ifndef sign_extend
130 static inline av_const int sign_extend(int val, unsigned bits)
131 {
132  unsigned shift = 8 * sizeof(int) - bits;
133  union { unsigned u; int s; } v = { (unsigned) val << shift };
134  return v.s >> shift;
135 }
136 #endif
137 
138 #ifndef zero_extend
139 static inline av_const unsigned zero_extend(unsigned val, unsigned bits)
140 {
141  return (val << ((8 * sizeof(int)) - bits)) >> ((8 * sizeof(int)) - bits);
142 }
143 #endif
144 
145 #ifndef COPY3_IF_LT
146 #define COPY3_IF_LT(x, y, a, b, c, d)\
147 if ((y) < (x)) {\
148  (x) = (y);\
149  (a) = (b);\
150  (c) = (d);\
151 }
152 #endif
153 
154 #ifndef MASK_ABS
155 #define MASK_ABS(mask, level) do { \
156  mask = level >> 31; \
157  level = (level ^ mask) - mask; \
158  } while (0)
159 #endif
160 
161 #ifndef NEG_SSR32
162 # define NEG_SSR32(a,s) ((( int32_t)(a))>>(32-(s)))
163 #endif
164 
165 #ifndef NEG_USR32
166 # define NEG_USR32(a,s) (((uint32_t)(a))>>(32-(s)))
167 #endif
168 
169 #if HAVE_BIGENDIAN
170 # ifndef PACK_2U8
171 # define PACK_2U8(a,b) (((a) << 8) | (b))
172 # endif
173 # ifndef PACK_4U8
174 # define PACK_4U8(a,b,c,d) (((a) << 24) | ((b) << 16) | ((c) << 8) | (d))
175 # endif
176 # ifndef PACK_2U16
177 # define PACK_2U16(a,b) (((a) << 16) | (b))
178 # endif
179 #else
180 # ifndef PACK_2U8
181 # define PACK_2U8(a,b) (((b) << 8) | (a))
182 # endif
183 # ifndef PACK_4U2
184 # define PACK_4U8(a,b,c,d) (((d) << 24) | ((c) << 16) | ((b) << 8) | (a))
185 # endif
186 # ifndef PACK_2U16
187 # define PACK_2U16(a,b) (((b) << 16) | (a))
188 # endif
189 #endif
190 
191 #ifndef PACK_2S8
192 # define PACK_2S8(a,b) PACK_2U8((a)&255, (b)&255)
193 #endif
194 #ifndef PACK_4S8
195 # define PACK_4S8(a,b,c,d) PACK_4U8((a)&255, (b)&255, (c)&255, (d)&255)
196 #endif
197 #ifndef PACK_2S16
198 # define PACK_2S16(a,b) PACK_2U16((a)&0xffff, (b)&0xffff)
199 #endif
200 
201 #ifndef FASTDIV
202 # define FASTDIV(a,b) ((uint32_t)((((uint64_t)a) * ff_inverse[b]) >> 32))
203 #endif /* FASTDIV */
204 
205 #ifndef ff_sqrt
206 #define ff_sqrt ff_sqrt
207 static inline av_const unsigned int ff_sqrt(unsigned int a)
208 {
209  unsigned int b;
210 
211  if (a < 255) return (ff_sqrt_tab[a + 1] - 1) >> 4;
212  else if (a < (1 << 12)) b = ff_sqrt_tab[a >> 4] >> 2;
213 #if !CONFIG_SMALL
214  else if (a < (1 << 14)) b = ff_sqrt_tab[a >> 6] >> 1;
215  else if (a < (1 << 16)) b = ff_sqrt_tab[a >> 8] ;
216 #endif
217  else {
218  int s = av_log2_16bit(a >> 16) >> 1;
219  unsigned int c = a >> (s + 2);
220  b = ff_sqrt_tab[c >> (s + 8)];
221  b = FASTDIV(c,b) + (b << s);
222  }
223 
224  return b - (a < b * b);
225 }
226 #endif
227 
228 static inline av_const float ff_sqrf(float a)
229 {
230  return a*a;
231 }
232 
233 static inline int8_t ff_u8_to_s8(uint8_t a)
234 {
235  union {
236  uint8_t u8;
237  int8_t s8;
238  } b;
239  b.u8 = a;
240  return b.s8;
241 }
242 
243 static av_always_inline uint32_t bitswap_32(uint32_t x)
244 {
245  return (uint32_t)ff_reverse[ x & 0xFF] << 24 |
246  (uint32_t)ff_reverse[(x >> 8) & 0xFF] << 16 |
247  (uint32_t)ff_reverse[(x >> 16) & 0xFF] << 8 |
248  (uint32_t)ff_reverse[ x >> 24];
249 }
250 
251 #endif /* AVCODEC_MATHOPS_H */
#define MUL64(a, b)
Definition: mathops.h:54
#define av_const
Definition: attributes.h:76
const char const char void * val
Definition: avisynth_c.h:771
const char * s
Definition: avisynth_c.h:768
static int shift(int a, int b)
Definition: sonic.c:82
const uint8_t ff_reverse[256]
Definition: reverse.c:23
static av_always_inline uint32_t bitswap_32(uint32_t x)
Definition: mathops.h:243
const char * b
Definition: vf_curves.c:113
#define MAX_NEG_CROP
Definition: mathops.h:31
static int8_t ff_u8_to_s8(uint8_t a)
Definition: mathops.h:233
int av_log2_16bit(unsigned v)
Definition: intmath.c:31
static av_const unsigned zero_extend(unsigned val, unsigned bits)
Definition: mathops.h:139
const uint32_t ff_inverse[257]
Definition: mathtables.c:27
uint8_t
#define u(width, name, range_min, range_max)
Definition: cbs_h2645.c:343
#define ff_sqrt
Definition: mathops.h:206
#define median4
Definition: mathops.h:116
const uint8_t ff_sqrt_tab[256]
Definition: mathtables.c:63
const uint8_t ff_zigzag_scan[16+1]
Definition: mathtables.c:109
#define FFMAX(a, b)
Definition: common.h:94
#define FFMIN(a, b)
Definition: common.h:96
static av_always_inline unsigned UMULH(unsigned a, unsigned b)
Definition: mathops.h:68
static av_const float ff_sqrf(float a)
Definition: mathops.h:228
#define FASTDIV(a, b)
Definition: mathops.h:202
const uint8_t ff_crop_tab[256+2 *MAX_NEG_CROP]
Definition: mathtables.c:77
const uint8_t ff_zigzag_direct[64]
Definition: mathtables.c:98
#define mid_pred
Definition: mathops.h:97
static av_always_inline int MULH(int a, int b)
Definition: mathops.h:62
static av_const int sign_extend(int val, unsigned bits)
Definition: mathops.h:130
int
common internal and external API header
static double c[64]
#define av_always_inline
Definition: attributes.h:39