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
|
/* See LICENSE file for copyright and license details. */
#include "stream.h"
#include "util.h"
#include <fcntl.h>
#include <stdint.h>
#include <string.h>
#include <unistd.h>
USAGE("[-iw] mask-stream")
static void
process_xyza(struct stream *colour, struct stream *mask, size_t n)
{
size_t i;
double w, y, yo;
for (i = 0; i < n; i += colour->pixel_size) {
w = ((double *)(mask->buf + i))[1];
w *= ((double *)(mask->buf + i))[3];
yo = ((double *)(colour->buf + i))[1];
y = (1 - yo) * w + yo * (1 - w);
((double *)(colour->buf + i))[0] += (y - yo) * D65_XYZ_X;
((double *)(colour->buf + i))[1] = y;
((double *)(colour->buf + i))[2] += (y - yo) * D65_XYZ_Z;
/*
* Explaination:
* Y is the luma and ((X / Xn - Y / Yn), (Z / Zn - Y / Yn))
* is the chroma (according to CIELAB), where (Xn, Yn, Zn)
* is the white point.
*/
}
}
static void
process_xyza_i(struct stream *colour, struct stream *mask, size_t n)
{
size_t i;
double w, y, yo;
for (i = 0; i < n; i += colour->pixel_size) {
w = 1 - ((double *)(mask->buf + i))[1];
w *= ((double *)(mask->buf + i))[3];
yo = ((double *)(colour->buf + i))[1];
y = (1 - yo) * w + yo * (1 - w);
((double *)(colour->buf + i))[0] += (y - yo) * D65_XYZ_X;
((double *)(colour->buf + i))[1] = y;
((double *)(colour->buf + i))[2] += (y - yo) * D65_XYZ_Z;
}
}
static void
process_xyza_w(struct stream *colour, struct stream *mask, size_t n)
{
size_t i;
double w, y, yo, X, Z;
for (i = 0; i < n; i += colour->pixel_size) {
X = ((double *)(mask->buf + i))[0];
Z = ((double *)(mask->buf + i))[2];
w = ((double *)(mask->buf + i))[1];
w *= ((double *)(mask->buf + i))[3];
yo = ((double *)(colour->buf + i))[1];
y = (1 - yo) * w + yo * (1 - w);
((double *)(colour->buf + i))[0] += (y - yo) * X;
((double *)(colour->buf + i))[1] = y;
((double *)(colour->buf + i))[2] += (y - yo) * Z;
}
}
static void
process_xyza_iw(struct stream *colour, struct stream *mask, size_t n)
{
size_t i;
double w, y, yo, X, Z;
for (i = 0; i < n; i += colour->pixel_size) {
X = ((double *)(mask->buf + i))[0];
Z = ((double *)(mask->buf + i))[2];
w = 1 - ((double *)(mask->buf + i))[1];
w *= ((double *)(mask->buf + i))[3];
yo = ((double *)(colour->buf + i))[1];
y = (1 - yo) * w + yo * (1 - w);
((double *)(colour->buf + i))[0] += (y - yo) * X;
((double *)(colour->buf + i))[1] = y;
((double *)(colour->buf + i))[2] += (y - yo) * Z;
}
}
int
main(int argc, char *argv[])
{
int invert = 0, whitepoint = 0;
struct stream colour, mask;
void (*process)(struct stream *colour, struct stream *mask, size_t n) = NULL;
ARGBEGIN {
case 'i':
invert = 1;
break;
case 'w':
whitepoint = 1;
break;
default:
usage();
} ARGEND;
if (argc != 1)
usage();
eopen_stream(&colour, NULL);
eopen_stream(&mask, argv[0]);
if (!strcmp(colour.pixfmt, "xyza"))
process = invert ? whitepoint ? process_xyza_iw : process_xyza_i
: whitepoint ? process_xyza_w : process_xyza;
else
eprintf("pixel format %s is not supported, try xyza\n", colour.pixfmt);
fprint_stream_head(stdout, &colour);
efflush(stdout, "<stdout>");
process_two_streams(&colour, &mask, STDOUT_FILENO, "<stdout>", process);
return 0;
}
|
