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-rw-r--r--libs/libqrencode/src/mmask.c177
1 files changed, 177 insertions, 0 deletions
diff --git a/libs/libqrencode/src/mmask.c b/libs/libqrencode/src/mmask.c
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+++ b/libs/libqrencode/src/mmask.c
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+/*
+ * 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;
+}