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
|
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* This file incorporates work covered by the following license notice:
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed
* with this work for additional information regarding copyright
* ownership. The ASF licenses this file to you under the Apache
* License, Version 2.0 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.apache.org/licenses/LICENSE-2.0 .
*/
#ifndef INCLUDED_BASEBMP_SCALEIMAGE_HXX
#define INCLUDED_BASEBMP_SCALEIMAGE_HXX
#include <osl/diagnose.h>
#include <vigra/tuple.hxx>
#include <vigra/copyimage.hxx>
#include <vigra/basicimage.hxx>
#include <vigra/iteratortraits.hxx>
namespace basebmp
{
template< class SourceIter, class SourceAcc,
class DestIter, class DestAcc >
void scaleLine( SourceIter s_begin,
SourceIter s_end,
SourceAcc s_acc,
DestIter d_begin,
DestIter d_end,
DestAcc d_acc )
{
const int src_width = s_end - s_begin;
const int dest_width = d_end - d_begin;
OSL_ASSERT( src_width > 0 && dest_width > 0 );
if( src_width >= dest_width )
{
// shrink
int rem = 0;
while( s_begin != s_end )
{
if( rem >= 0 )
{
d_acc.set( s_acc(s_begin), d_begin );
rem -= src_width;
++d_begin;
}
rem += dest_width;
++s_begin;
}
}
else
{
// enlarge
int rem = -dest_width;
while( d_begin != d_end )
{
if( rem >= 0 )
{
rem -= dest_width;
++s_begin;
}
d_acc.set( s_acc(s_begin), d_begin );
rem += src_width;
++d_begin;
}
}
}
/** Scale an image using zero order interpolation (pixel replication)
Source and destination range must be at least one pixel wide and
high.
@param s_begin
Start iterator for source image
@param s_end
End iterator for source image
@param s_acc
Source accessor
@param d_begin
Start iterator for destination image
@param d_end
End iterator for destination image
@param d_acc
Destination accessor
@param bMustCopy
When true, scaleImage always copies source, even when doing 1:1
copy
*/
template< class SourceIter, class SourceAcc,
class DestIter, class DestAcc >
void scaleImage( SourceIter s_begin,
SourceIter s_end,
SourceAcc s_acc,
DestIter d_begin,
DestIter d_end,
DestAcc d_acc,
bool bMustCopy=false )
{
const int src_width ( s_end.x - s_begin.x );
const int src_height( s_end.y - s_begin.y );
const int dest_width ( d_end.x - d_begin.x );
const int dest_height( d_end.y - d_begin.y );
if( !bMustCopy &&
src_width == dest_width &&
src_height == dest_height )
{
// no scaling involved, can simply copy
vigra::copyImage( s_begin, s_end, s_acc,
d_begin, d_acc );
return;
}
typedef vigra::BasicImage<typename SourceAcc::value_type> TmpImage;
typedef typename TmpImage::traverser TmpImageIter;
TmpImage tmp_image(src_width,
dest_height);
TmpImageIter t_begin = tmp_image.upperLeft();
// scale in y direction
for( int x=0; x<src_width; ++x, ++s_begin.x, ++t_begin.x )
{
typename SourceIter::column_iterator s_cbegin = s_begin.columnIterator();
typename TmpImageIter::column_iterator t_cbegin = t_begin.columnIterator();
scaleLine(s_cbegin, s_cbegin+src_height, s_acc,
t_cbegin, t_cbegin+dest_height, tmp_image.accessor());
}
t_begin = tmp_image.upperLeft();
// scale in x direction
for( int y=0; y<dest_height; ++y, ++d_begin.y, ++t_begin.y )
{
typename DestIter::row_iterator d_rbegin = d_begin.rowIterator();
typename TmpImageIter::row_iterator t_rbegin = t_begin.rowIterator();
scaleLine(t_rbegin, t_rbegin+src_width, tmp_image.accessor(),
d_rbegin, d_rbegin+dest_width, d_acc);
}
}
/** Scale an image, range tuple version
@param bMustCopy
When true, scaleImage always copies source, even when doing 1:1
copy
*/
template< class SourceIter, class SourceAcc,
class DestIter, class DestAcc >
inline void scaleImage( vigra::triple<SourceIter,SourceIter,SourceAcc> const& src,
vigra::triple<DestIter,DestIter,DestAcc> const& dst,
bool bMustCopy=false )
{
scaleImage(src.first,src.second,src.third,
dst.first,dst.second,dst.third,
bMustCopy);
}
}
#endif /* INCLUDED_BASEBMP_SCALEIMAGE_HXX */
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
|