/*
* simple math operations
* Copyright (c) 2001, 2002 Fabrice Bellard
* Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at> et al
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef AVCODEC_MATHOPS_H
#define AVCODEC_MATHOPS_H
#include <stdint.h>
#include "libavutil/common.h"
#include "config.h"
extern const uint32_t ff_inverse[257];
extern const uint8_t ff_reverse[256];
extern const uint8_t ff_sqrt_tab[256];
#if ARCH_ARM
# include "arm/mathops.h"
#elif ARCH_AVR32
# include "avr32/mathops.h"
#elif ARCH_BFIN
# include "bfin/mathops.h"
#elif ARCH_MIPS
# include "mips/mathops.h"
#elif ARCH_PPC
# include "ppc/mathops.h"
#elif ARCH_X86
# include "x86/mathops.h"
#endif
/* generic implementation */
#ifndef MUL64
# define MUL64(a,b) ((int64_t)(a) * (int64_t)(b))
#endif
#ifndef MULL
# define MULL(a,b,s) (MUL64(a, b) >> (s))
#endif
#ifndef MULH
static av_always_inline int MULH(int a, int b){
return MUL64(a, b) >> 32;
}
#endif
#ifndef UMULH
static av_always_inline unsigned UMULH(unsigned a, unsigned b){
return ((uint64_t)(a) * (uint64_t)(b))>>32;
}
#endif
#ifndef MAC64
# define MAC64(d, a, b) ((d) += MUL64(a, b))
#endif
#ifndef MLS64
# define MLS64(d, a, b) ((d) -= MUL64(a, b))
#endif
/* signed 16x16 -> 32 multiply add accumulate */
#ifndef MAC16
# define MAC16(rt, ra, rb) rt += (ra) * (rb)
#endif
/* signed 16x16 -> 32 multiply */
#ifndef MUL16
# define MUL16(ra, rb) ((ra) * (rb))
#endif
#ifndef MLS16
# define MLS16(rt, ra, rb) ((rt) -= (ra) * (rb))
#endif
/* median of 3 */
#ifndef mid_pred
#define mid_pred mid_pred
static inline av_const int mid_pred(int a, int b, int c)
{
#if 0
int t= (a-b)&((a-b)>>31);
a-=t;
b+=t;
b-= (b-c)&((b-c)>>31);
b+= (a-b)&((a-b)>>31);
return b;
#else
if(a>b){
if(c>b){
if(c>a) b=a;
else b=c;
}
}else{
if(b>c){
if(c>a) b=c;
else b=a;
}
}
return b;
#endif
}
#endif
#ifndef sign_extend
static inline av_const int sign_extend(int val, unsigned bits)
{
unsigned shift = 8 * sizeof(int) - bits;
union { unsigned u; int s; } v = { (unsigned) val << shift };
return v.s >> shift;
}
#endif
#ifndef zero_extend
static inline av_const unsigned zero_extend(unsigned val, unsigned bits)
{
return (val << ((8 * sizeof(int)) - bits)) >> ((8 * sizeof(int)) - bits);
}
#endif
#ifndef COPY3_IF_LT
#define COPY3_IF_LT(x, y, a, b, c, d)\
if ((y) < (x)) {\
(x) = (y);\
(a) = (b);\
(c) = (d);\
}
#endif
#ifndef MASK_ABS
#define MASK_ABS(mask, level) do { \
mask = level >> 31; \
level = (level ^ mask) - mask; \
} while (0)
#endif
#ifndef NEG_SSR32
# define NEG_SSR32(a,s) ((( int32_t)(a))>>(32-(s)))
#endif
#ifndef NEG_USR32
# define NEG_USR32(a,s) (((uint32_t)(a))>>(32-(s)))
#endif
#if HAVE_BIGENDIAN
# ifndef PACK_2U8
# define PACK_2U8(a,b) (((a) << 8) | (b))
# endif
# ifndef PACK_4U8
# define PACK_4U8(a,b,c,d) (((a) << 24) | ((b) << 16) | ((c) << 8) | (d))
# endif
# ifndef PACK_2U16
# define PACK_2U16(a,b) (((a) << 16) | (b))
# endif
#else
# ifndef PACK_2U8
# define PACK_2U8(a,b) (((b) << 8) | (a))
# endif
# ifndef PACK_4U2
# define PACK_4U8(a,b,c,d) (((d) << 24) | ((c) << 16) | ((b) << 8) | (a))
# endif
# ifndef PACK_2U16
# define PACK_2U16(a,b) (((b) << 16) | (a))
# endif
#endif
#ifndef PACK_2S8
# define PACK_2S8(a,b) PACK_2U8((a)&255, (b)&255)
#endif
#ifndef PACK_4S8
# define PACK_4S8(a,b,c,d) PACK_4U8((a)&255, (b)&255, (c)&255, (d)&255)
#endif
#ifndef PACK_2S16
# define PACK_2S16(a,b) PACK_2U16((a)&0xffff, (b)&0xffff)
#endif
#ifndef FASTDIV
# define FASTDIV(a,b) ((uint32_t)((((uint64_t)a) * ff_inverse[b]) >> 32))
#endif /* FASTDIV */
#ifndef MOD_UNLIKELY
# define MOD_UNLIKELY(modulus, dividend, divisor, prev_dividend) \
do { \
if ((prev_dividend) == 0 || (dividend) - (prev_dividend) != (divisor)) \
(modulus) = (dividend) % (divisor); \
(prev_dividend) = (dividend); \
} while (0)
#endif
static inline av_const unsigned int ff_sqrt(unsigned int a)
{
unsigned int b;
if (a < 255) return (ff_sqrt_tab[a + 1] - 1) >> 4;
else if (a < (1 << 12)) b = ff_sqrt_tab[a >> 4] >> 2;
#if !CONFIG_SMALL
else if (a < (1 << 14)) b = ff_sqrt_tab[a >> 6] >> 1;
else if (a < (1 << 16)) b = ff_sqrt_tab[a >> 8] ;
#endif
else {
int s = av_log2_16bit(a >> 16) >> 1;
unsigned int c = a >> (s + 2);
b = ff_sqrt_tab[c >> (s + 8)];
b = FASTDIV(c,b) + (b << s);
}
return b - (a < b * b);
}
static inline int8_t ff_u8_to_s8(uint8_t a)
{
union {
uint8_t u8;
int8_t s8;
} b;
b.u8 = a;
return b.s8;
}
#endif /* AVCODEC_MATHOPS_H */