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
|
/* creates a 2d sinewave
*
* Copyright: 1990, N. Dessipris.
*
* Author: Nicos Dessipris
* Written on: 02/02/1990
* Modified on:
* 22/7/93 JC
* - externs removed
* - im_outcheck() added
* 1/2/11
* - gtk-doc
* 13/6/13
* - redo as a class
*/
/*
This file is part of VIPS.
VIPS is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2 of the License, 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 Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA
*/
/*
These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk
*/
/*
#define VIPS_DEBUG
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /*HAVE_CONFIG_H*/
#include <glib/gi18n-lib.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <math.h>
#include <vips/vips.h>
#include "pcreate.h"
#include "point.h"
typedef struct _VipsSines {
VipsPoint parent_instance;
double hfreq;
double vfreq;
double c;
double sintheta;
double costheta;
} VipsSines;
typedef VipsPointClass VipsSinesClass;
G_DEFINE_TYPE(VipsSines, vips_sines, VIPS_TYPE_POINT);
static float
vips_sines_point(VipsPoint *point, int x, int y)
{
VipsSines *sines = (VipsSines *) point;
return cos(sines->c * (x * sines->costheta - y * sines->sintheta));
}
static int
vips_sines_build(VipsObject *object)
{
VipsPoint *point = VIPS_POINT(object);
VipsSines *sines = (VipsSines *) object;
double theta;
double factor;
if (VIPS_OBJECT_CLASS(vips_sines_parent_class)->build(object))
return -1;
theta = sines->hfreq == 0.0
? VIPS_PI / 2.0
: atan(sines->vfreq / sines->hfreq);
factor = sqrt(sines->hfreq * sines->hfreq +
sines->vfreq * sines->vfreq);
sines->costheta = cos(theta);
sines->sintheta = sin(theta);
sines->c = factor * VIPS_PI * 2.0 / point->width;
return 0;
}
static void
vips_sines_class_init(VipsSinesClass *class)
{
GObjectClass *gobject_class = G_OBJECT_CLASS(class);
VipsObjectClass *vobject_class = VIPS_OBJECT_CLASS(class);
VipsPointClass *point_class = VIPS_POINT_CLASS(class);
gobject_class->set_property = vips_object_set_property;
gobject_class->get_property = vips_object_get_property;
vobject_class->nickname = "sines";
vobject_class->description = _("make a 2D sine wave");
vobject_class->build = vips_sines_build;
point_class->point = vips_sines_point;
VIPS_ARG_DOUBLE(class, "hfreq", 6,
_("hfreq"),
_("Horizontal spatial frequency"),
VIPS_ARGUMENT_OPTIONAL_INPUT,
G_STRUCT_OFFSET(VipsSines, hfreq),
0.0, 10000.0, 0.5);
VIPS_ARG_DOUBLE(class, "vfreq", 7,
_("vfreq"),
_("Vertical spatial frequency"),
VIPS_ARGUMENT_OPTIONAL_INPUT,
G_STRUCT_OFFSET(VipsSines, vfreq),
0.0, 10000.0, 0.5);
}
static void
vips_sines_init(VipsSines *sines)
{
sines->hfreq = 0.5;
sines->vfreq = 0.5;
}
/**
* vips_sines:
* @out: (out): output image
* @width: image size
* @height: image size
* @...: %NULL-terminated list of optional named arguments
*
* Optional arguments:
*
* * @hfreq: horizontal frequency
* * @vreq: vertical frequency
* * @uchar: output a uchar image
*
* Creates a float one band image of the a sine waveform in two
* dimensions.
*
* The number of horizontal and vertical spatial frequencies are
* determined by the variables @hfreq and @vfreq respectively. The
* function is useful for creating displayable sine waves and
* square waves in two dimensions.
*
* If horfreq and verfreq are integers the resultant image is periodical
* and therefore the Fourier transform does not present spikes
*
* Pixels are normally in [-1, +1], set @uchar to output [0, 255].
*
* See also: vips_grey(), vips_xyz().
*
* Returns: 0 on success, -1 on error
*/
int
vips_sines(VipsImage **out, int width, int height, ...)
{
va_list ap;
int result;
va_start(ap, height);
result = vips_call_split("sines", ap, out, width, height);
va_end(ap);
return result;
}
|
