summaryrefslogtreecommitdiff
path: root/wx+/image_tools.h
blob: c50116349b791ecb12f99ebda35e4bb926b88737 (plain)
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
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
// **************************************************************************
// * This file is part of the FreeFileSync project. It is distributed under *
// * GNU General Public License: http://www.gnu.org/licenses/gpl.html       *
// * Copyright (C) ZenJu (zenju AT gmx DOT de) - All Rights Reserved        *
// **************************************************************************

#ifndef IMAGE_TOOLS_HEADER_45782456427634254
#define IMAGE_TOOLS_HEADER_45782456427634254

#include <numeric>
#include <wx/bitmap.h>
#include <wx/image.h>
#include <wx/dcmemory.h>
#include <zen/basic_math.h>

namespace zen
{
wxBitmap greyScale(const wxBitmap& bmp); //greyscale + brightness adaption
wxBitmap layOver(const wxBitmap& foreground, const wxBitmap& background); //merge

void move(wxImage& img, int up, int left = 0);
void adjustBrightness(wxImage& img, int targetLevel);
double getAvgBrightness(const wxImage& img); //in [0, 255]
void brighten(wxImage& img, int level); //level: delta per channel in points

bool isEqual(const wxBitmap& lhs, const wxBitmap& rhs); //pixel-wise equality (respecting alpha channel)

wxColor gradient(const wxColor& from, const wxColor& to, double fraction); //maps fraction within [0, 1] to an intermediate color

wxColour hsvColor(double h, double s, double v); //h within [0, 360), s, v within [0, 1]














//################################### implementation ###################################
inline
void move(wxImage& img, int up, int left)
{
    img = img.GetSubImage(wxRect(std::max(0, left), std::max(0, up), img.GetWidth() - abs(left), img.GetHeight() - abs(up)));
    img.Resize(wxSize(img.GetWidth() + abs(left), img.GetHeight() + abs(up)), wxPoint(-std::min(0, left), -std::min(0, up)));
}


inline
wxBitmap greyScale(const wxBitmap& bmp)
{
    wxImage output = bmp.ConvertToImage().ConvertToGreyscale(1.0 / 3, 1.0 / 3, 1.0 / 3); //treat all channels equally!
    //wxImage output = bmp.ConvertToImage().ConvertToGreyscale();
    adjustBrightness(output, 160);
    return output;
}


inline
double getAvgBrightness(const wxImage& img)
{
    const int pixelCount = img.GetWidth() * img.GetHeight();
    auto pixBegin = img.GetData();

    if (pixelCount > 0 && pixBegin)
    {
        auto pixEnd = pixBegin + 3 * pixelCount; //RGB

        if (img.HasAlpha())
        {
            const unsigned char* alphaFirst = img.GetAlpha();

            //calculate average weighted by alpha channel
            double dividend = 0;
            for (auto iter = pixBegin; iter != pixEnd; ++iter)
                dividend += *iter * static_cast<double>(alphaFirst[(iter - pixBegin) / 3]);

            const double divisor = 3.0 * std::accumulate(alphaFirst, alphaFirst + pixelCount, 0.0);

            return numeric::isNull(divisor) ? 0 : dividend / divisor;
        }
        else
            return std::accumulate(pixBegin, pixEnd, 0.0) / (3.0 * pixelCount);
    }
    return 0;
}


inline
void brighten(wxImage& img, int level)
{
    const int pixelCount = img.GetWidth() * img.GetHeight();
    auto pixBegin = img.GetData();
    if (pixBegin)
    {
        auto pixEnd = pixBegin + 3 * pixelCount; //RGB
        if (level > 0)
            std::for_each(pixBegin, pixEnd, [&](unsigned char& c) { c = std::min(255, c + level); });
        else
            std::for_each(pixBegin, pixEnd, [&](unsigned char& c) { c = std::max(0, c + level); });
    }
}


inline
void adjustBrightness(wxImage& img, int targetLevel)
{
    brighten(img, targetLevel - getAvgBrightness(img));
}


inline
wxBitmap layOver(const wxBitmap& foreground, const wxBitmap& background)
{
    wxBitmap output = background;
    {
        wxMemoryDC dc;
        dc.SelectObject(output);
        dc.DrawBitmap(foreground, 0, 0, true);
        dc.SelectObject(wxNullBitmap);
    }
    return output;
}


inline
bool isEqual(const wxBitmap& lhs, const wxBitmap& rhs)
{
    if (lhs.IsOk() != rhs.IsOk())
        return false;
    if (!lhs.IsOk())
        return true;

    const int pixelCount = lhs.GetWidth() * lhs.GetHeight();
    if (pixelCount != rhs.GetWidth() * rhs.GetHeight())
        return false;

    wxImage imLhs = lhs.ConvertToImage();
    wxImage imRhs = rhs.ConvertToImage();

    if (imLhs.HasAlpha() != imRhs.HasAlpha())
        return false;

    if (imLhs.HasAlpha())
    {
        if (!std::equal(imLhs.GetAlpha(), imLhs.GetAlpha() + pixelCount, imRhs.GetAlpha()))
            return false;
    }

    return std::equal(imLhs.GetData(), imLhs.GetData() + pixelCount * 3, imRhs.GetData());
}

inline
wxColor gradient(const wxColor& from, const wxColor& to, double fraction)
{
    fraction = std::max(0.0, fraction);
    fraction = std::min(1.0, fraction);
    return wxColor(from.Red  () + (to.Red  () - from.Red  ()) * fraction,
                   from.Green() + (to.Green() - from.Green()) * fraction,
                   from.Blue () + (to.Blue () - from.Blue ()) * fraction,
                   from.Alpha() + (to.Alpha() - from.Alpha()) * fraction);
}


inline
wxColour hsvColor(double h, double s, double v) //h within [0, 360), s, v within [0, 1]
{
    //http://de.wikipedia.org/wiki/HSV-Farbraum

    //make input values fit into bounds
    if (h > 360)
        h -= static_cast<int>(h / 360) * 360;
    else if (h < 0)
        h -= static_cast<int>(h / 360) * 360 - 360;
    numeric::confine<double>(s, 0, 1);
    numeric::confine<double>(v, 0, 1);
    //------------------------------------
    const int h_i = h / 60;
    const float f = h / 60 - h_i;

    auto polish = [](double val) -> unsigned char
    {
        int result = numeric::round(val * 255);
        numeric::confine(result, 0, 255);
        return static_cast<unsigned char>(result);
    };

    const unsigned char p  = polish(v * (1 - s));
    const unsigned char q  = polish(v * (1 - s * f));
    const unsigned char t  = polish(v * (1 - s * (1 - f)));
    const unsigned char vi = polish(v);

    switch (h_i)
    {
        case 0:
            return wxColour(vi, t, p);
        case 1:
            return wxColour(q, vi, p);
        case 2:
            return wxColour(p, vi, t);
        case 3:
            return wxColour(p, q, vi);
        case 4:
            return wxColour(t, p, vi);
        case 5:
            return wxColour(vi, p, q);
    }
    assert(false);
    return *wxBLACK;
}
}

#endif //IMAGE_TOOLS_HEADER_45782456427634254
bgstack15