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
|
/*
* Copyright 2017 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "SkColorSpace.h"
#include "SkRasterPipeline.h"
#include "Test.h"
static void check_error(skiatest::Reporter* r, float limit, SkColorSpaceTransferFn fn) {
float in[256], out[256];
for (int i = 0; i < 256; i++) {
in [i] = i / 255.0f;
out[i] = 0.0f; // Not likely important. Just being tidy.
}
const float* ip = in;
float* op = out;
SkRasterPipeline_<256> p;
p.append(SkRasterPipeline::load_f32, &ip);
p.append(SkRasterPipeline::parametric_r, &fn);
p.append(SkRasterPipeline::parametric_g, &fn);
p.append(SkRasterPipeline::parametric_b, &fn);
p.append(SkRasterPipeline::parametric_a, &fn);
p.append(SkRasterPipeline::store_f32, &op);
p.run(0,0, 256/4);
for (int i = 0; i < 256; i++) {
float want = (in[i] <= fn.fD) ? fn.fC * in[i] + fn.fF
: powf(in[i] * fn.fA + fn.fB, fn.fG) + fn.fE;
float err = fabsf(out[i] - want);
if (err > limit) {
ERRORF(r, "At %d, error was %g (got %g, want %g)", i, err, out[i], want);
}
}
}
static void check_error(skiatest::Reporter* r, float limit, float gamma) {
SkColorSpaceTransferFn fn = {0,0,0,0,0,0,0};
fn.fG = gamma;
fn.fA = 1;
check_error(r, limit, fn);
}
DEF_TEST(Parametric_sRGB, r) {
// Test our good buddy the sRGB transfer function in resplendent 7-parameter glory.
check_error(r, 1/510.0f, {
2.4f,
1.0f / 1.055f,
0.055f / 1.055f,
1.0f / 12.92f,
0.04045f,
0.0f,
0.0f,
});
}
// A nice little spread of simple gammas.
DEF_TEST(Parametric_1dot0, r) { check_error(r, 1/510.0f, 1.0f); }
DEF_TEST(Parametric_1dot2, r) { check_error(r, 1/510.0f, 1.2f); }
DEF_TEST(Parametric_1dot4, r) { check_error(r, 1/510.0f, 1.4f); }
DEF_TEST(Parametric_1dot8, r) { check_error(r, 1/510.0f, 1.8f); }
DEF_TEST(Parametric_2dot0, r) { check_error(r, 1/510.0f, 2.0f); }
DEF_TEST(Parametric_2dot2, r) { check_error(r, 1/510.0f, 2.2f); }
DEF_TEST(Parametric_2dot4, r) { check_error(r, 1/510.0f, 2.4f); }
DEF_TEST(Parametric_inv_1dot2, r) { check_error(r, 1/510.0f, 1/1.2f); }
DEF_TEST(Parametric_inv_1dot4, r) { check_error(r, 1/510.0f, 1/1.4f); }
DEF_TEST(Parametric_inv_1dot8, r) { check_error(r, 1/510.0f, 1/1.8f); }
DEF_TEST(Parametric_inv_2dot0, r) { check_error(r, 1/510.0f, 1/2.0f); }
DEF_TEST(Parametric_inv_2dot2, r) { check_error(r, 1/510.0f, 1/2.2f); }
DEF_TEST(Parametric_inv_2dot4, r) { check_error(r, 1/510.0f, 1/2.4f); }
|
