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
|
/*
* qrencode - QR Code encoder
*
* Masking for Micro QR Code.
* Copyright (C) 2006-2017 Kentaro Fukuchi <kentaro@fukuchi.org>
*
* This library 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 2.1 of the License, or any later version.
*
* This library 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 library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#if HAVE_CONFIG_H
# include "config.h"
#endif
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#include <errno.h>
#include "qrencode.h"
#include "mqrspec.h"
#include "mmask.h"
STATIC_IN_RELEASE void MMask_writeFormatInformation(int version, int width, unsigned char *frame, int mask, QRecLevel level)
{
unsigned int format;
unsigned char v;
int i;
format = MQRspec_getFormatInfo(mask, version, level);
for(i = 0; i < 8; i++) {
v = 0x84 | (format & 1);
frame[width * (i + 1) + 8] = v;
format = format >> 1;
}
for(i = 0; i < 7; i++) {
v = 0x84 | (format & 1);
frame[width * 8 + 7 - i] = v;
format = format >> 1;
}
}
#define MASKMAKER(__exp__) \
int x, y;\
\
for(y = 0; y < width; y++) {\
for(x = 0; x < width; x++) {\
if(*s & 0x80) {\
*d = *s;\
} else {\
*d = *s ^ ((__exp__) == 0);\
}\
s++; d++;\
}\
}
static void Mask_mask0(int width, const unsigned char *s, unsigned char *d)
{
MASKMAKER(y&1)
}
static void Mask_mask1(int width, const unsigned char *s, unsigned char *d)
{
MASKMAKER(((y/2)+(x/3))&1)
}
static void Mask_mask2(int width, const unsigned char *s, unsigned char *d)
{
MASKMAKER((((x*y)&1)+(x*y)%3)&1)
}
static void Mask_mask3(int width, const unsigned char *s, unsigned char *d)
{
MASKMAKER((((x+y)&1)+((x*y)%3))&1)
}
#define maskNum (4)
typedef void MaskMaker(int, const unsigned char *, unsigned char *);
static MaskMaker *maskMakers[maskNum] = {
Mask_mask0, Mask_mask1, Mask_mask2, Mask_mask3
};
#ifdef WITH_TESTS
unsigned char *MMask_makeMaskedFrame(int width, unsigned char *frame, int mask)
{
unsigned char *masked;
masked = (unsigned char *)malloc((size_t)(width * width));
if(masked == NULL) return NULL;
maskMakers[mask](width, frame, masked);
return masked;
}
#endif
unsigned char *MMask_makeMask(int version, unsigned char *frame, int mask, QRecLevel level)
{
unsigned char *masked;
int width;
if(mask < 0 || mask >= maskNum) {
errno = EINVAL;
return NULL;
}
width = MQRspec_getWidth(version);
masked = (unsigned char *)malloc((size_t)(width * width));
if(masked == NULL) return NULL;
maskMakers[mask](width, frame, masked);
MMask_writeFormatInformation(version, width, masked, mask, level);
return masked;
}
STATIC_IN_RELEASE int MMask_evaluateSymbol(int width, unsigned char *frame)
{
int x, y;
unsigned char *p;
int sum1 = 0, sum2 = 0;
p = frame + width * (width - 1);
for(x = 1; x < width; x++) {
sum1 += (p[x] & 1);
}
p = frame + width * 2 - 1;
for(y = 1; y < width; y++) {
sum2 += (*p & 1);
p += width;
}
return (sum1 <= sum2)?(sum1 * 16 + sum2):(sum2 * 16 + sum1);
}
unsigned char *MMask_mask(int version, unsigned char *frame, QRecLevel level)
{
int i;
unsigned char *mask, *bestMask;
int maxScore = 0;
int score;
int width;
width = MQRspec_getWidth(version);
mask = (unsigned char *)malloc((size_t)(width * width));
if(mask == NULL) return NULL;
bestMask = NULL;
for(i = 0; i < maskNum; i++) {
score = 0;
maskMakers[i](width, frame, mask);
MMask_writeFormatInformation(version, width, mask, i, level);
score = MMask_evaluateSymbol(width, mask);
if(score > maxScore) {
maxScore = score;
free(bestMask);
bestMask = mask;
mask = (unsigned char *)malloc((size_t)(width * width));
if(mask == NULL) break;
}
}
free(mask);
return bestMask;
}
|
