2 * simple math operations
3 * Copyright (c) 2001, 2002 Fabrice Bellard
4 * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at> et al
6 * This file is part of FFmpeg.
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.
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.
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
22 #ifndef AVCODEC_MATHOPS_H
23 #define AVCODEC_MATHOPS_H
27 #include "libavutil/common.h"
30 #define MAX_NEG_CROP 1024
32 extern const uint32_t ff_inverse
[257];
33 extern const uint8_t ff_reverse
[256];
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];
39 # include "arm/mathops.h"
41 # include "avr32/mathops.h"
43 # include "mips/mathops.h"
45 # include "ppc/mathops.h"
47 # include "x86/mathops.h"
50 /* generic implementation */
53 # define MUL64(a,b) ((int64_t)(a) * (int64_t)(b))
57 # define MULL(a,b,s) (MUL64(a, b) >> (s))
61 static av_always_inline
int MULH(int a
, int b
){
62 return MUL64(a
, b
) >> 32;
67 static av_always_inline
unsigned UMULH(unsigned a
, unsigned b
){
68 return ((uint64_t)(a
) * (uint64_t)(b
))>>32;
73 # define MAC64(d, a, b) ((d) += MUL64(a, b))
77 # define MLS64(d, a, b) ((d) -= MUL64(a, b))
80 /* signed 16x16 -> 32 multiply add accumulate */
82 # define MAC16(rt, ra, rb) rt += (ra) * (rb)
85 /* signed 16x16 -> 32 multiply */
87 # define MUL16(ra, rb) ((ra) * (rb))
91 # define MLS16(rt, ra, rb) ((rt) -= (ra) * (rb))
96 #define mid_pred mid_pred
97 static inline av_const
int mid_pred(int a
, int b
, int c
)
100 int t
= (a
-b
)&((a
-b
)>>31);
103 b
-= (b
-c
)&((b
-c
)>>31);
104 b
+= (a
-b
)&((a
-b
)>>31);
125 static inline av_const
int sign_extend(int val
, unsigned bits
)
127 unsigned shift
= 8 * sizeof(int) - bits
;
128 union { unsigned u
; int s
; } v
= { (unsigned) val
<< shift
};
134 static inline av_const
unsigned zero_extend(unsigned val
, unsigned bits
)
136 return (val
<< ((8 * sizeof(int)) - bits
)) >> ((8 * sizeof(int)) - bits
);
141 #define COPY3_IF_LT(x, y, a, b, c, d)\
150 #define MASK_ABS(mask, level) do { \
151 mask = level >> 31; \
152 level = (level ^ mask) - mask; \
157 # define NEG_SSR32(a,s) ((( int32_t)(a))>>(32-(s)))
161 # define NEG_USR32(a,s) (((uint32_t)(a))>>(32-(s)))
166 # define PACK_2U8(a,b) (((a) << 8) | (b))
169 # define PACK_4U8(a,b,c,d) (((a) << 24) | ((b) << 16) | ((c) << 8) | (d))
172 # define PACK_2U16(a,b) (((a) << 16) | (b))
176 # define PACK_2U8(a,b) (((b) << 8) | (a))
179 # define PACK_4U8(a,b,c,d) (((d) << 24) | ((c) << 16) | ((b) << 8) | (a))
182 # define PACK_2U16(a,b) (((b) << 16) | (a))
187 # define PACK_2S8(a,b) PACK_2U8((a)&255, (b)&255)
190 # define PACK_4S8(a,b,c,d) PACK_4U8((a)&255, (b)&255, (c)&255, (d)&255)
193 # define PACK_2S16(a,b) PACK_2U16((a)&0xffff, (b)&0xffff)
197 # define FASTDIV(a,b) ((uint32_t)((((uint64_t)a) * ff_inverse[b]) >> 32))
200 static inline av_const
unsigned int ff_sqrt(unsigned int a
)
204 if (a
< 255) return (ff_sqrt_tab
[a
+ 1] - 1) >> 4;
205 else if (a
< (1 << 12)) b
= ff_sqrt_tab
[a
>> 4] >> 2;
207 else if (a
< (1 << 14)) b
= ff_sqrt_tab
[a
>> 6] >> 1;
208 else if (a
< (1 << 16)) b
= ff_sqrt_tab
[a
>> 8] ;
211 int s
= av_log2_16bit(a
>> 16) >> 1;
212 unsigned int c
= a
>> (s
+ 2);
213 b
= ff_sqrt_tab
[c
>> (s
+ 8)];
214 b
= FASTDIV(c
,b
) + (b
<< s
);
217 return b
- (a
< b
* b
);
220 static inline int8_t ff_u8_to_s8(uint8_t a
)
230 #endif /* AVCODEC_MATHOPS_H */