cpp/core/src/zxing/oned/MultiFormatUPCEANReader.cpp

   1 /*
   2  *  MultiFormatUPCEANReader.cpp
   3  *  ZXing
   4  *
   5  *  Copyright 2010 ZXing authors All rights reserved.
   6  *
   7  * Licensed under the Apache License, Version 2.0 (the "License");
   8  * you may not use this file except in compliance with the License.
   9  * You may obtain a copy of the License at
  10  *
  11  *      http://www.apache.org/licenses/LICENSE-2.0
  12  *
  13  * Unless required by applicable law or agreed to in writing, software
  14  * distributed under the License is distributed on an "AS IS" BASIS,
  15  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16  * See the License for the specific language governing permissions and
  17  * limitations under the License.
  18  */
  19 #include "MultiFormatUPCEANReader.h"
  20
  21 #include <zxing/oned/EAN13Reader.h>
  22 #include <zxing/oned/EAN8Reader.h>
  23 #include <zxing/oned/UPCEReader.h>
  24 #include <zxing/oned/UPCAReader.h>
  25 #include <zxing/oned/OneDResultPoint.h>
  26 #include <zxing/common/Array.h>
  27 #include <zxing/ReaderException.h>
  28 #include <math.h>
  29
  30 namespace zxing {
  31         namespace oned {
  32
  33                 MultiFormatUPCEANReader::MultiFormatUPCEANReader(DecodeHints hints) : readers() {
  34                   if (hints.containsFormat(BarcodeFormat_EAN_13)) {
  35                     readers.push_back(Ref<OneDReader>(new EAN13Reader()));
  36                   } else if (hints.containsFormat(BarcodeFormat_UPC_A)) {
  37                     readers.push_back(Ref<OneDReader>(new UPCAReader()));
  38                   }
  39                   if (hints.containsFormat(BarcodeFormat_EAN_8)) {
  40                     readers.push_back(Ref<OneDReader>(new EAN8Reader()));
  41                   }
  42                   if (hints.containsFormat(BarcodeFormat_UPC_E)) {
  43                     readers.push_back(Ref<OneDReader>(new UPCEReader()));
  44                   }
  45                   if (readers.size() == 0) {
  46               readers.push_back(Ref<OneDReader>(new EAN13Reader()));
  47               // UPC-A is covered by EAN-13
  48               readers.push_back(Ref<OneDReader>(new EAN8Reader()));
  49               readers.push_back(Ref<OneDReader>(new UPCEReader()));
  50                   }
  51                 }
  52
  53                 Ref<Result> MultiFormatUPCEANReader::decodeRow(int rowNumber, Ref<BitArray> row) {
  54                         // Compute this location once and reuse it on multiple implementations
  55                         int size = readers.size();
  56                         for (int i = 0; i < size; i++) {
  57                                 Ref<OneDReader> reader = readers[i];
  58                                 Ref<Result> result = reader->decodeRow(rowNumber, row);
  59                                 if (result.empty()) {
  60                                   continue;
  61                                 }
  62
  63                                 // Special case: a 12-digit code encoded in UPC-A is identical to a "0"
  64                                 // followed by those 12 digits encoded as EAN-13. Each will recognize such a code,
  65                                 // UPC-A as a 12-digit string and EAN-13 as a 13-digit string starting with "0".
  66                                 // Individually these are correct and their readers will both read such a code
  67                                 // and correctly call it EAN-13, or UPC-A, respectively.
  68                                 //
  69                                 // In this case, if we've been looking for both types, we'd like to call it
  70                                 // a UPC-A code. But for efficiency we only run the EAN-13 decoder to also read
  71                                 // UPC-A. So we special case it here, and convert an EAN-13 result to a UPC-A
  72                                 // result if appropriate.
  73                                 if (result->getBarcodeFormat() == BarcodeFormat_EAN_13) {
  74                                         const std::string& text = (result->getText())->getText();
  75                                         if (text[0] == '0') {
  76                                                 Ref<String> resultString(new String(text.substr(1)));
  77                                                 Ref<Result> res(new Result(resultString, result->getRawBytes(),
  78                                                     result->getResultPoints(), BarcodeFormat_UPC_A));
  79                                                 return res;
  80                                         }
  81                                 }
  82                                 return result;
  83                         }
  84                         return Ref<Result>();
  85                 }
  86         }
  87 }