1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
|
/*
* Copyright (c) 2005 Adrian Page <adrian@pagenet.plus.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#ifndef KIS_INTEGER_MATHS_H
#define KIS_INTEGER_MATHS_H
#include <config.h>
#if defined(HAVE_STDINT_H)
#include <stdint.h>
#endif
#if !defined(UINT8_MAX)
#define UINT8_MAX 255u
#endif
#if !defined(UINT8_MIN)
#define UINT8_MIN 0u
#endif
#if !defined(UINT16_MAX)
#define UINT16_MAX 65535u
#endif
#if !defined(UINT16_MIN)
#define UINT16_MIN 0u
#endif
#if !defined(UINT32_MAX)
#define UINT32_MAX (4294967295u)
#endif
#if !defined(UINT32_MIN)
#define UINT32_MIN 0u
#endif
#if !defined(INT16_MAX)
#define INT16_MAX 32767
#endif
#if !defined(INT16_MIN)
#define INT16_MIN -32768
#endif
/// take a and scale it up by 256*b/255
inline uint UINT8_SCALEBY(uint a, uint b)
{
uint c = a * b + 0x80u;
return (c >> 8) + c;
}
inline uint UINT8_MULT(uint a, uint b)
{
uint c = a * b + 0x80u;
return ((c >> 8) + c) >> 8;
}
inline uint UINT8_DIVIDE(uint a, uint b)
{
uint c = (a * UINT8_MAX + (b / 2u)) / b;
return c;
}
inline uint UINT8_BLEND(uint a, uint b, uint alpha)
{
// Basically we do a*alpha + b*(1-alpha)
// However refactored to (a-b)*alpha + b since that saves a multiplication
// Signed arithmetic is needed since a-b might be negative
int c = ((int(a) - int(b)) * int(alpha)) >> 8;
return uint(c + b);
}
inline uint UINT16_MULT(uint a, uint b)
{
uint c = a * b + 0x8000u;
return ((c >> 16) + c) >> 16;
}
inline int INT16_MULT(int a, int b)
{
return (a*b) / INT16_MAX;
}
inline uint UINT16_DIVIDE(uint a, uint b)
{
uint c = (a * UINT16_MAX + (b / 2u)) / b;
return c;
}
inline uint UINT16_BLEND(uint a, uint b, uint alpha)
{
// Basically we do a*alpha + b*(1-alpha)
// However refactored to (a-b)*alpha + b since that saves a multiplication
// Signed arithmetic is needed since a-b might be negative
int c = ((int(a) - int(b)) * int(alpha)) >> 16;
return uint(c + b);
}
inline uint UINT8_TO_UINT16(uint c)
{
return c | (c<<8);
}
inline uint UINT16_TO_UINT8(uint c)
{
//return round(c / 257.0);
//For all UINT16 this calculation is the same and a lot faster (off by c/65656 which for every c is 0)
c = c - (c >> 8) + 128;
return c >>8;
}
inline int INT16_BLEND(int a, int b, uint alpha)
{
// Basically we do a*alpha + b*(1-alpha)
// However refactored to (a-b)*alpha + b since that saves a multiplication
int c = ((int(a) - int(b)) * int(alpha)) >> 16;
return c + b;
}
#endif
|
