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
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
|
/* ============================================================
*
* This file is a part of digiKam project
* http://www.digikam.org
*
* Date : 2005-17-07
* Description : A Sharpen threaded image filter.
*
* Copyright (C) 2005-2007 by Gilles Caulier <caulier dot gilles at gmail dot com>
*
* Original Sharpen algorithm copyright 2002
* by Daniel M. Duley <mosfet@kde.org> from KImageEffect API.
*
* 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, 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.
*
* ============================================================ */
#define SQ2PI 2.50662827463100024161235523934010416269302368164062
#define Epsilon 1.0e-12
// C++ includes.
#include <cmath>
#include <cstdlib>
// Local includes.
#include "ddebug.h"
#include "dimgimagefilters.h"
#include "dimgsharpen.h"
namespace Digikam
{
DImgSharpen::DImgSharpen(DImg *orgImage, TQObject *parent, double radius, double sigma)
: DImgThreadedFilter(orgImage, parent, "Sharpen")
{
m_radius = radius;
m_sigma = sigma;
initFilter();
}
DImgSharpen::DImgSharpen(DImgThreadedFilter *parentFilter,
const DImg &orgImage, const DImg &destImage,
int progressBegin, int progressEnd, double radius, double sigma)
: DImgThreadedFilter(parentFilter, orgImage, destImage, progressBegin, progressEnd,
parentFilter->filterName() + ": Sharpen")
{
m_radius = radius;
m_sigma = sigma;
// We need to provide support for orgImage == destImage.
// The algorithm does not support this out of the box, so use a temporary.
if (orgImage.bits() == destImage.bits())
m_destImage = DImg(destImage.width(), destImage.height(), destImage.sixteenBit());
filterImage();
if (orgImage.bits() == destImage.bits())
memcpy(destImage.bits(), m_destImage.bits(), m_destImage.numBytes());
}
void DImgSharpen::filterImage(void)
{
sharpenImage(m_radius, m_sigma);
}
/** Function to apply the sharpen filter on an image*/
void DImgSharpen::sharpenImage(double radius, double sigma)
{
if (m_orgImage.isNull())
{
DWarning() << k_funcinfo << "No image data available!"
<< endl;
return;
}
if (radius <= 0.0)
{
m_destImage = m_orgImage;
return;
}
double alpha, normalize=0.0;
long i=0, u, v;
int kernelWidth = getOptimalKernelWidth(radius, sigma);
if((int)m_orgImage.width() < kernelWidth)
{
DWarning() << k_funcinfo << "Image is smaller than radius!"
<< endl;
return;
}
double *kernel = new double[kernelWidth*kernelWidth];
if(!kernel)
{
DWarning() << k_funcinfo << "Unable to allocate memory!"
<< endl;
return;
}
for(v=(-kernelWidth/2) ; v <= (kernelWidth/2) ; v++)
{
for(u=(-kernelWidth/2) ; u <= (kernelWidth/2) ; u++)
{
alpha = exp(-((double) u*u+v*v)/(2.0*sigma*sigma));
kernel[i] = alpha/(2.0*M_PI*sigma*sigma);
normalize += kernel[i];
i++;
}
}
kernel[i/2] = (-2.0)*normalize;
convolveImage(kernelWidth, kernel);
delete [] kernel;
}
bool DImgSharpen::convolveImage(const unsigned int order, const double *kernel)
{
uint x, y;
int mx, my, sx, sy, mcx, mcy, progress;
long kernelWidth, i;
double red, green, blue, alpha, normalize=0.0;
double *k=0;
DColor color;
kernelWidth = order;
if((kernelWidth % 2) == 0)
{
DWarning() << k_funcinfo << "Kernel width must be an odd number!"
<< endl;
return(false);
}
double *normal_kernel = new double[kernelWidth*kernelWidth];
if(!normal_kernel)
{
DWarning() << k_funcinfo << "Unable to allocate memory!"
<< endl;
return(false);
}
for(i=0 ; i < (kernelWidth*kernelWidth) ; i++)
normalize += kernel[i];
if(fabs(normalize) <= Epsilon)
normalize=1.0;
normalize = 1.0/normalize;
for(i=0 ; i < (kernelWidth*kernelWidth) ; i++)
normal_kernel[i] = normalize*kernel[i];
double maxClamp = m_destImage.sixteenBit() ? 16777215.0 : 65535.0;
for(y=0 ; !m_cancel && (y < m_destImage.height()) ; y++)
{
sy = y-(kernelWidth/2);
for(x=0 ; !m_cancel && (x < m_destImage.width()) ; x++)
{
k = normal_kernel;
red = green = blue = alpha = 0;
sy = y-(kernelWidth/2);
for(mcy=0 ; !m_cancel && (mcy < kernelWidth) ; mcy++, sy++)
{
my = sy < 0 ? 0 : sy > (int)m_destImage.height()-1 ? m_destImage.height()-1 : sy;
sx = x+(-kernelWidth/2);
for(mcx=0 ; !m_cancel && (mcx < kernelWidth) ; mcx++, sx++)
{
mx = sx < 0 ? 0 : sx > (int)m_destImage.width()-1 ? m_destImage.width()-1 : sx;
color = m_orgImage.getPixelColor(mx, my);
red += (*k)*(color.red() * 257.0);
green += (*k)*(color.green() * 257.0);
blue += (*k)*(color.blue() * 257.0);
alpha += (*k)*(color.alpha() * 257.0);
k++;
}
}
red = red < 0.0 ? 0.0 : red > maxClamp ? maxClamp : red+0.5;
green = green < 0.0 ? 0.0 : green > maxClamp ? maxClamp : green+0.5;
blue = blue < 0.0 ? 0.0 : blue > maxClamp ? maxClamp : blue+0.5;
alpha = alpha < 0.0 ? 0.0 : alpha > maxClamp ? maxClamp : alpha+0.5;
m_destImage.setPixelColor(x, y, DColor((int)(red / 257UL), (int)(green / 257UL),
(int)(blue / 257UL), (int)(alpha / 257UL),
m_destImage.sixteenBit()));
}
progress = (int)(((double)y * 100.0) / m_destImage.height());
if ( progress%5 == 0 )
postProgress( progress );
}
delete [] normal_kernel;
return(true);
}
int DImgSharpen::getOptimalKernelWidth(double radius, double sigma)
{
double normalize, value;
long kernelWidth;
long u;
if(radius > 0.0)
return((int)(2.0*ceil(radius)+1.0));
for(kernelWidth=5; ;)
{
normalize=0.0;
for(u=(-kernelWidth/2) ; u <= (kernelWidth/2) ; u++)
normalize += exp(-((double) u*u)/(2.0*sigma*sigma))/(SQ2PI*sigma);
u = kernelWidth/2;
value = exp(-((double) u*u)/(2.0*sigma*sigma))/(SQ2PI*sigma)/normalize;
if((long)(65535*value) <= 0)
break;
kernelWidth+=2;
}
return((int)kernelWidth-2);
}
} // NameSpace Digikam
|
