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
|
/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
* Copyright (C) 2024, Ideas On Board
*
* Helper for radial polynomial used in lens shading correction.
*/
#pragma once
#include <algorithm>
#include <array>
#include <assert.h>
#include <cmath>
#include <libcamera/base/log.h>
#include <libcamera/base/span.h>
#include "libcamera/internal/yaml_parser.h"
namespace libcamera {
LOG_DECLARE_CATEGORY(LscPolynomial)
namespace ipa {
class LscPolynomial
{
public:
LscPolynomial(double cx = 0.0, double cy = 0.0, double k0 = 0.0,
double k1 = 0.0, double k2 = 0.0, double k3 = 0.0,
double k4 = 0.0)
: cx_(cx), cy_(cy), cnx_(0), cny_(0),
coefficients_({ k0, k1, k2, k3, k4 })
{
}
double sampleAtNormalizedPixelPos(double x, double y) const
{
double dx = x - cnx_;
double dy = y - cny_;
double r = sqrt(dx * dx + dy * dy);
double res = 1.0;
for (unsigned int i = 0; i < coefficients_.size(); i++) {
res += coefficients_[i] * std::pow(r, (i + 1) * 2);
}
return res;
}
double getM() const
{
double cpx = imageSize_.width * cx_;
double cpy = imageSize_.height * cy_;
double mx = std::max(cpx, std::fabs(imageSize_.width - cpx));
double my = std::max(cpy, std::fabs(imageSize_.height - cpy));
return sqrt(mx * mx + my * my);
}
void setReferenceImageSize(const Size &size)
{
assert(!size.isNull());
imageSize_ = size;
/* Calculate normalized centers */
double m = getM();
cnx_ = (size.width * cx_) / m;
cny_ = (size.height * cy_) / m;
}
private:
double cx_;
double cy_;
double cnx_;
double cny_;
std::array<double, 5> coefficients_;
Size imageSize_;
};
} /* namespace ipa */
#ifndef __DOXYGEN__
template<>
struct YamlObject::Getter<ipa::LscPolynomial> {
std::optional<ipa::LscPolynomial> get(const YamlObject &obj) const
{
std::optional<double> cx = obj["cx"].get<double>();
std::optional<double> cy = obj["cy"].get<double>();
std::optional<double> k0 = obj["k0"].get<double>();
std::optional<double> k1 = obj["k1"].get<double>();
std::optional<double> k2 = obj["k2"].get<double>();
std::optional<double> k3 = obj["k3"].get<double>();
std::optional<double> k4 = obj["k4"].get<double>();
if (!(cx && cy && k0 && k1 && k2 && k3 && k4))
LOG(LscPolynomial, Error)
<< "Polynomial is missing a parameter";
return ipa::LscPolynomial(*cx, *cy, *k0, *k1, *k2, *k3, *k4);
}
};
#endif
} /* namespace libcamera */
|