symbian/QQrDecoder/zxing/oned/UPCEANReader.cpp

   1 /*
   2  *  UPCEANReader.cpp
   3  *  ZXing
   4  *
   5  *  Created by Lukasz Warchol on 10-01-21.
   6  *  Copyright 2010 ZXing authors All rights reserved.
   7  *
   8  * Licensed under the Apache License, Version 2.0 (the "License");
   9  * you may not use this file except in compliance with the License.
  10  * You may obtain a copy of the License at
  11  *
  12  *      http://www.apache.org/licenses/LICENSE-2.0
  13  *
  14  * Unless required by applicable law or agreed to in writing, software
  15  * distributed under the License is distributed on an "AS IS" BASIS,
  16  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  17  * See the License for the specific language governing permissions and
  18  * limitations under the License.
  19  */
  20
  21 #include "UPCEANReader.h"
  22 #include <zxing/oned/OneDResultPoint.h>
  23 #include <zxing/ReaderException.h>
  24 namespace zxing {
  25         namespace oned {
  26
  27                 /**
  28                  * Start/end guard pattern.
  29                  */
  30                 static const int START_END_PATTERN[3] = {1, 1, 1};
  31
  32                 /**
  33                  * Pattern marking the middle of a UPC/EAN pattern, separating the two halves.
  34                  */
  35                 static const int MIDDLE_PATTERN_LEN = 5;
  36                 static const int MIDDLE_PATTERN[MIDDLE_PATTERN_LEN] = {1, 1, 1, 1, 1};
  37
  38                 /**
  39                  * "Odd", or "L" patterns used to encode UPC/EAN digits.
  40                  */
  41                 const int L_PATTERNS_LEN = 10;
  42                 const int L_PATTERNS_SUB_LEN = 4;
  43                 const int L_PATTERNS[10][4] = {
  44                         {3, 2, 1, 1}, // 0
  45                         {2, 2, 2, 1}, // 1
  46                         {2, 1, 2, 2}, // 2
  47                         {1, 4, 1, 1}, // 3
  48                         {1, 1, 3, 2}, // 4
  49                         {1, 2, 3, 1}, // 5
  50                         {1, 1, 1, 4}, // 6
  51                         {1, 3, 1, 2}, // 7
  52                         {1, 2, 1, 3}, // 8
  53                         {3, 1, 1, 2}  // 9
  54                 };
  55
  56                 /**
  57                  * As above but also including the "even", or "G" patterns used to encode UPC/EAN digits.
  58                  */
  59                 const int L_AND_G_PATTERNS_LEN = 20;
  60                 const int L_AND_G_PATTERNS_SUB_LEN = 4;
  61                 const int L_AND_G_PATTERNS[L_AND_G_PATTERNS_LEN][L_AND_G_PATTERNS_SUB_LEN] = {
  62                         {3, 2, 1, 1}, // 0
  63                         {2, 2, 2, 1}, // 1
  64                         {2, 1, 2, 2}, // 2
  65                         {1, 4, 1, 1}, // 3
  66                         {1, 1, 3, 2}, // 4
  67                         {1, 2, 3, 1}, // 5
  68                         {1, 1, 1, 4}, // 6
  69                         {1, 3, 1, 2}, // 7
  70                         {1, 2, 1, 3}, // 8
  71                         {3, 1, 1, 2}, // 9
  72                         {1, 1, 2, 3}, // 10 reversed 0
  73                         {1, 2, 2, 2}, // 11 reversed 1
  74                         {2, 2, 1, 2}, // 12 reversed 2
  75                         {1, 1, 4, 1}, // 13 reversed 3
  76                         {2, 3, 1, 1}, // 14 reversed 4
  77                         {1, 3, 2, 1}, // 15 reversed 5
  78                         {4, 1, 1, 1}, // 16 reversed 6
  79                         {2, 1, 3, 1}, // 17 reversed 7
  80                         {3, 1, 2, 1}, // 18 reversed 8
  81                         {2, 1, 1, 3}  // 19 reversed 9
  82                 };
  83
  84
  85                 const int UPCEANReader::getMIDDLE_PATTERN_LEN(){
  86                         return MIDDLE_PATTERN_LEN;
  87                 }
  88                 const int* UPCEANReader::getMIDDLE_PATTERN(){
  89                         return MIDDLE_PATTERN;
  90                 }
  91
  92                 UPCEANReader::UPCEANReader(){
  93                 }
  94
  95
  96                 Ref<Result> UPCEANReader::decodeRow(int rowNumber, Ref<BitArray> row){
  97                         return decodeRow(rowNumber, row, findStartGuardPattern(row));
  98                 }
  99                 Ref<Result> UPCEANReader::decodeRow(int rowNumber, Ref<BitArray> row, int startGuardRange[]){
 100
 101                         std::string tmpResultString;
 102                         std::string& tmpResultStringRef = tmpResultString;
 103                         int endStart = decodeMiddle(row, startGuardRange, 2 /*reference findGuardPattern*/ , tmpResultStringRef);
 104
 105                         int* endRange = decodeEnd(row, endStart);
 106
 107 #pragma mark QuietZone needs some change
 108                         // Make sure there is a quiet zone at least as big as the end pattern after the barcode. The
 109                         // spec might want more whitespace, but in practice this is the maximum we can count on.
 110 //                      int end = endRange[1];
 111 //                      int quietEnd = end + (end - endRange[0]);
 112 //                      if (quietEnd >= row->getSize() || !row->isRange(end, quietEnd, false)) {
 113 //                              throw ReaderException("Quiet zone asserrt fail.");
 114 //                      }
 115
 116                         if (!checkChecksum(tmpResultString)) {
 117                                 throw ReaderException("Checksum fail.");
 118                         }
 119
 120                         Ref<String> resultString(new String(tmpResultString));
 121
 122                         float left = (float) (startGuardRange[1] + startGuardRange[0]) / 2.0f;
 123                         float right = (float) (endRange[1] + endRange[0]) / 2.0f;
 124
 125                         std::vector< Ref<ResultPoint> > resultPoints(2);
 126                         Ref<OneDResultPoint> resultPoint1(new OneDResultPoint(left, (float) rowNumber));
 127                         Ref<OneDResultPoint> resultPoint2(new OneDResultPoint(right, (float) rowNumber));
 128                         resultPoints[0] = resultPoint1;
 129                         resultPoints[1] = resultPoint2;
 130
 131                         ArrayRef<unsigned char> resultBytes(1);
 132
 133                         if (startGuardRange!=NULL) {
 134                                 delete [] startGuardRange;
 135                                 startGuardRange = NULL;
 136                         }
 137                         if (endRange!=NULL) {
 138                                 delete [] endRange;
 139                                 endRange = NULL;
 140                         }
 141
 142                         Ref<Result> res(new Result(resultString, resultBytes, resultPoints, getBarcodeFormat()));
 143                         return res;
 144                 }
 145
 146                 int* UPCEANReader::findStartGuardPattern(Ref<BitArray> row){
 147                         bool foundStart = false;
 148
 149                         int* startRange = NULL;
 150                         int nextStart = 0;
 151                         while (!foundStart) {
 152                                 startRange = findGuardPattern(row, nextStart, false, START_END_PATTERN, sizeof(START_END_PATTERN)/sizeof(int));
 153                                 int start = startRange[0];
 154                                 nextStart = startRange[1];
 155                                 // Make sure there is a quiet zone at least as big as the start pattern before the barcode.
 156                                 // If this check would run off the left edge of the image, do not accept this barcode,
 157                                 // as it is very likely to be a false positive.
 158                                 int quietStart = start - (nextStart - start);
 159                                 if (quietStart >= 0) {
 160                                         foundStart = row->isRange(quietStart, start, false);
 161                                 }
 162                         }
 163                         return startRange;
 164                 }
 165
 166                 int* UPCEANReader::findGuardPattern(Ref<BitArray> row, int rowOffset, bool whiteFirst, const int pattern[], int patternLen){
 167                         int patternLength = patternLen;
 168
 169                         //int counters[patternLength];
 170                         int* counters = new int(patternLength);
 171                         int countersCount = sizeof(counters)/sizeof(int);
 172                         for (int i=0; i<countersCount ; i++) {
 173                                 counters[i]=0;
 174                         }
 175                         int width = row->getSize();
 176                         bool isWhite = false;
 177                         while (rowOffset < width) {
 178                                 isWhite = !row->get(rowOffset);
 179                                 if (whiteFirst == isWhite) {
 180                                         break;
 181                                 }
 182                                 rowOffset++;
 183                         }
 184
 185                         int counterPosition = 0;
 186                         int patternStart = rowOffset;
 187                         for (int x = rowOffset; x < width; x++) {
 188                                 bool pixel = row->get(x);
 189                                 if (pixel ^ isWhite) {
 190                                         counters[counterPosition]++;
 191                                 } else {
 192                                         if (counterPosition == patternLength - 1) {
 193                                                 if (patternMatchVariance(counters, countersCount, pattern, MAX_INDIVIDUAL_VARIANCE) < MAX_AVG_VARIANCE) {
 194                                                         int* resultValue = new int[2];
 195                                                         resultValue[0] = patternStart;
 196                                                         resultValue[1] = x;
 197                                                         return resultValue;
 198                                                 }
 199                                                 patternStart += counters[0] + counters[1];
 200                                                 for (int y = 2; y < patternLength; y++) {
 201                                                         counters[y - 2] = counters[y];
 202                                                 }
 203                                                 counters[patternLength - 2] = 0;
 204                                                 counters[patternLength - 1] = 0;
 205                                                 counterPosition--;
 206                                         } else {
 207                                                 counterPosition++;
 208                                         }
 209                                         counters[counterPosition] = 1;
 210                                         isWhite = !isWhite;
 211                                 }
 212                         }
 213                         delete counters;
 214                         throw ReaderException("findGuardPattern");
 215                 }
 216
 217                 int* UPCEANReader::decodeEnd(Ref<BitArray> row, int endStart){
 218                         return findGuardPattern(row, endStart, false, START_END_PATTERN, sizeof(START_END_PATTERN)/sizeof(int));
 219                 }
 220
 221 //              int UPCEANReader::decodeDigit(Ref<BitArray> row, int counters[], int countersLen, int rowOffset, int** patterns/*[][]*/, int paterns1Len, int paterns2Len)
 222                 int UPCEANReader::decodeDigit(Ref<BitArray> row, int counters[], int countersLen, int rowOffset, UPC_EAN_PATTERNS paternType){
 223                         recordPattern(row, rowOffset, counters, countersLen);
 224                         int bestVariance = MAX_AVG_VARIANCE; // worst variance we'll accept
 225                         int bestMatch = -1;
 226
 227                         int max = 0;
 228                         switch (paternType) {
 229                                 case UPC_EAN_PATTERNS_L_PATTERNS:
 230                                         max = L_PATTERNS_LEN;
 231                                         for (int i = 0; i < max; i++) {
 232                                                 //int pattern[countersLen];
 233                                                 int* pattern = new int(countersLen);
 234                                                 for(int j = 0; j< countersLen; j++){
 235                                                         pattern[j] = L_PATTERNS[i][j];
 236                                                 }
 237
 238                                                 int variance = patternMatchVariance(counters, countersLen, pattern, MAX_INDIVIDUAL_VARIANCE);
 239                                                 if (variance < bestVariance) {
 240                                                         bestVariance = variance;
 241                                                         bestMatch = i;
 242                                                 }
 243                                                 delete pattern;
 244                                         }
 245                                         break;
 246                                 case UPC_EAN_PATTERNS_L_AND_G_PATTERNS:
 247                                         max = L_AND_G_PATTERNS_LEN;
 248                                         for (int i = 0; i < max; i++) {
 249                                                 //int pattern[countersLen];
 250                                                 int* pattern = new int(countersLen);
 251                                                 for(int j = 0; j< countersLen; j++){
 252                                                         pattern[j] = L_AND_G_PATTERNS[i][j];
 253                                                 }
 254
 255                                                 int variance = patternMatchVariance(counters, countersLen, pattern, MAX_INDIVIDUAL_VARIANCE);
 256                                                 if (variance < bestVariance) {
 257                                                         bestVariance = variance;
 258                                                         bestMatch = i;
 259                                                 }
 260                                                 delete pattern;
 261                                         }
 262                                         break;
 263                                 default:
 264                                         break;
 265                         }
 266                         if (bestMatch >= 0) {
 267                                 return bestMatch;
 268                         } else {
 269                                 throw ReaderException("UPCEANReader::decodeDigit: No best mach");
 270                         }
 271                 }
 272
 273
 274                 /**
 275                  * @return {@link #checkStandardUPCEANChecksum(String)}
 276                  */
 277                 bool UPCEANReader::checkChecksum(std::string s){
 278                         return checkStandardUPCEANChecksum(s);
 279                 }
 280
 281                 /**
 282                  * Computes the UPC/EAN checksum on a string of digits, and reports
 283                  * whether the checksum is correct or not.
 284                  *
 285                  * @param s string of digits to check
 286                  * @return true iff string of digits passes the UPC/EAN checksum algorithm
 287                  * @throws ReaderException if the string does not contain only digits
 288                  */
 289                 bool UPCEANReader::checkStandardUPCEANChecksum(std::string s){
 290                         int length = s.length();
 291                         if (length == 0) {
 292                                 return false;
 293                         }
 294
 295                         int sum = 0;
 296                         for (int i = length - 2; i >= 0; i -= 2) {
 297                                 int digit = (int) s[i] - (int) '0';
 298                                 if (digit < 0 || digit > 9) {
 299                                         throw ReaderException("checkStandardUPCEANChecksum");
 300                                 }
 301                                 sum += digit;
 302                         }
 303                         sum *= 3;
 304                         for (int i = length - 1; i >= 0; i -= 2) {
 305                                 int digit = (int) s[i] - (int) '0';
 306                                 if (digit < 0 || digit > 9) {
 307                                         throw ReaderException("checkStandardUPCEANChecksum");
 308                                 }
 309                                 sum += digit;
 310                         }
 311                         return sum % 10 == 0;
 312                 }
 313                 UPCEANReader::~UPCEANReader(){
 314                 }
 315         }
 316 }