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-rw-r--r--libs/libqrencode/src/mask.c357
1 files changed, 357 insertions, 0 deletions
diff --git a/libs/libqrencode/src/mask.c b/libs/libqrencode/src/mask.c
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+++ b/libs/libqrencode/src/mask.c
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+/*
+ * qrencode - QR Code encoder
+ *
+ * Masking.
+ * 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 "qrspec.h"
+#include "mask.h"
+
+STATIC_IN_RELEASE int Mask_writeFormatInformation(int width, unsigned char *frame, int mask, QRecLevel level)
+{
+ unsigned int format;
+ unsigned char v;
+ int i;
+ int blacks = 0;
+
+ format = QRspec_getFormatInfo(mask, level);
+
+ for(i = 0; i < 8; i++) {
+ if(format & 1) {
+ blacks += 2;
+ v = 0x85;
+ } else {
+ v = 0x84;
+ }
+ frame[width * 8 + width - 1 - i] = v;
+ if(i < 6) {
+ frame[width * i + 8] = v;
+ } else {
+ frame[width * (i + 1) + 8] = v;
+ }
+ format= format >> 1;
+ }
+ for(i = 0; i < 7; i++) {
+ if(format & 1) {
+ blacks += 2;
+ v = 0x85;
+ } else {
+ v = 0x84;
+ }
+ frame[width * (width - 7 + i) + 8] = v;
+ if(i == 0) {
+ frame[width * 8 + 7] = v;
+ } else {
+ frame[width * 8 + 6 - i] = v;
+ }
+ format= format >> 1;
+ }
+
+ return blacks;
+}
+
+/**
+ * Demerit coefficients.
+ * See Section 8.8.2, pp.45, JIS X0510:2004.
+ */
+#define N1 (3)
+#define N2 (3)
+#define N3 (40)
+#define N4 (10)
+
+#define MASKMAKER(__exp__) \
+ int x, y;\
+ int b = 0;\
+\
+ for(y = 0; y < width; y++) {\
+ for(x = 0; x < width; x++) {\
+ if(*s & 0x80) {\
+ *d = *s;\
+ } else {\
+ *d = *s ^ ((__exp__) == 0);\
+ }\
+ b += (int)(*d & 1);\
+ s++; d++;\
+ }\
+ }\
+ return b;
+
+static int Mask_mask0(int width, const unsigned char *s, unsigned char *d)
+{
+ MASKMAKER((x+y)&1)
+}
+
+static int Mask_mask1(int width, const unsigned char *s, unsigned char *d)
+{
+ MASKMAKER(y&1)
+}
+
+static int Mask_mask2(int width, const unsigned char *s, unsigned char *d)
+{
+ MASKMAKER(x%3)
+}
+
+static int Mask_mask3(int width, const unsigned char *s, unsigned char *d)
+{
+ MASKMAKER((x+y)%3)
+}
+
+static int Mask_mask4(int width, const unsigned char *s, unsigned char *d)
+{
+ MASKMAKER(((y/2)+(x/3))&1)
+}
+
+static int Mask_mask5(int width, const unsigned char *s, unsigned char *d)
+{
+ MASKMAKER(((x*y)&1)+(x*y)%3)
+}
+
+static int Mask_mask6(int width, const unsigned char *s, unsigned char *d)
+{
+ MASKMAKER((((x*y)&1)+(x*y)%3)&1)
+}
+
+static int Mask_mask7(int width, const unsigned char *s, unsigned char *d)
+{
+ MASKMAKER((((x*y)%3)+((x+y)&1))&1)
+}
+
+#define maskNum (8)
+typedef int MaskMaker(int, const unsigned char *, unsigned char *);
+static MaskMaker *maskMakers[maskNum] = {
+ Mask_mask0, Mask_mask1, Mask_mask2, Mask_mask3,
+ Mask_mask4, Mask_mask5, Mask_mask6, Mask_mask7
+};
+
+#ifdef WITH_TESTS
+unsigned char *Mask_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 *Mask_makeMask(int width, unsigned char *frame, int mask, QRecLevel level)
+{
+ unsigned char *masked;
+
+ if(mask < 0 || mask >= maskNum) {
+ errno = EINVAL;
+ return NULL;
+ }
+
+ masked = (unsigned char *)malloc((size_t)(width * width));
+ if(masked == NULL) return NULL;
+
+ maskMakers[mask](width, frame, masked);
+ Mask_writeFormatInformation(width, masked, mask, level);
+
+ return masked;
+}
+
+
+//static int n1;
+//static int n2;
+//static int n3;
+//static int n4;
+
+STATIC_IN_RELEASE int Mask_calcN1N3(int length, int *runLength)
+{
+ int i;
+ int demerit = 0;
+ int fact;
+
+ for(i = 0; i < length; i++) {
+ if(runLength[i] >= 5) {
+ demerit += N1 + (runLength[i] - 5);
+ //n1 += N1 + (runLength[i] - 5);
+ }
+ if((i & 1)) {
+ if(i >= 3 && i < length-2 && (runLength[i] % 3) == 0) {
+ fact = runLength[i] / 3;
+ if(runLength[i-2] == fact &&
+ runLength[i-1] == fact &&
+ runLength[i+1] == fact &&
+ runLength[i+2] == fact) {
+ if(i == 3 || runLength[i-3] >= 4 * fact) {
+ demerit += N3;
+ //n3 += N3;
+ } else if(i+4 >= length || runLength[i+3] >= 4 * fact) {
+ demerit += N3;
+ //n3 += N3;
+ }
+ }
+ }
+ }
+ }
+
+ return demerit;
+}
+
+STATIC_IN_RELEASE int Mask_calcN2(int width, unsigned char *frame)
+{
+ int x, y;
+ unsigned char *p;
+ unsigned char b22, w22;
+ int demerit = 0;
+
+ p = frame + width + 1;
+ for(y = 1; y < width; y++) {
+ for(x = 1; x < width; x++) {
+ b22 = p[0] & p[-1] & p[-width] & p [-width-1];
+ w22 = p[0] | p[-1] | p[-width] | p [-width-1];
+ if((b22 | (w22 ^ 1))&1) {
+ demerit += N2;
+ }
+ p++;
+ }
+ p++;
+ }
+
+ return demerit;
+}
+
+STATIC_IN_RELEASE int Mask_calcRunLengthH(int width, unsigned char *frame, int *runLength)
+{
+ int head;
+ int i;
+ unsigned char prev;
+
+ if(frame[0] & 1) {
+ runLength[0] = -1;
+ head = 1;
+ } else {
+ head = 0;
+ }
+ runLength[head] = 1;
+ prev = frame[0];
+
+ for(i = 1; i < width; i++) {
+ if((frame[i] ^ prev) & 1) {
+ head++;
+ runLength[head] = 1;
+ prev = frame[i];
+ } else {
+ runLength[head]++;
+ }
+ }
+
+ return head + 1;
+}
+
+STATIC_IN_RELEASE int Mask_calcRunLengthV(int width, unsigned char *frame, int *runLength)
+{
+ int head;
+ int i;
+ unsigned char prev;
+
+ if(frame[0] & 1) {
+ runLength[0] = -1;
+ head = 1;
+ } else {
+ head = 0;
+ }
+ runLength[head] = 1;
+ prev = frame[0];
+
+ for(i = 1; i < width; i++) {
+ if((frame[i * width] ^ prev) & 1) {
+ head++;
+ runLength[head] = 1;
+ prev = frame[i * width];
+ } else {
+ runLength[head]++;
+ }
+ }
+
+ return head + 1;
+}
+
+STATIC_IN_RELEASE int Mask_evaluateSymbol(int width, unsigned char *frame)
+{
+ int x, y;
+ int demerit = 0;
+ int runLength[QRSPEC_WIDTH_MAX + 1];
+ int length;
+
+ demerit += Mask_calcN2(width, frame);
+
+ for(y = 0; y < width; y++) {
+ length = Mask_calcRunLengthH(width, frame + y * width, runLength);
+ demerit += Mask_calcN1N3(length, runLength);
+ }
+
+ for(x = 0; x < width; x++) {
+ length = Mask_calcRunLengthV(width, frame + x, runLength);
+ demerit += Mask_calcN1N3(length, runLength);
+ }
+
+ return demerit;
+}
+
+unsigned char *Mask_mask(int width, unsigned char *frame, QRecLevel level)
+{
+ int i;
+ unsigned char *mask, *bestMask;
+ int minDemerit = INT_MAX;
+ int blacks;
+ int bratio;
+ int demerit;
+ int w2 = width * width;
+
+ mask = (unsigned char *)malloc((size_t)w2);
+ if(mask == NULL) return NULL;
+ bestMask = (unsigned char *)malloc((size_t)w2);
+ if(bestMask == NULL) {
+ free(mask);
+ return NULL;
+ }
+
+ for(i = 0; i < maskNum; i++) {
+// n1 = n2 = n3 = n4 = 0;
+ demerit = 0;
+ blacks = maskMakers[i](width, frame, mask);
+ blacks += Mask_writeFormatInformation(width, mask, i, level);
+ bratio = (200 * blacks + w2) / w2 / 2; /* (int)(100*blacks/w2+0.5) */
+ demerit = (abs(bratio - 50) / 5) * N4;
+// n4 = demerit;
+ demerit += Mask_evaluateSymbol(width, mask);
+// printf("(%d,%d,%d,%d)=%d\n", n1, n2, n3 ,n4, demerit);
+ if(demerit < minDemerit) {
+ minDemerit = demerit;
+ memcpy(bestMask, mask, (size_t)w2);
+ }
+ }
+ free(mask);
+ return bestMask;
+}