Exemplo n.º 1
0
        //JAVA TO C# CONVERTER WARNING: Method 'throws' clauses are not available in .NET:
        //ORIGINAL LINE: public com.google.zxing.Result decodeRow(int rowNumber, com.google.zxing.common.BitArray row, java.util.Map<com.google.zxing.DecodeHintType,?> hints) throws com.google.zxing.NotFoundException, com.google.zxing.FormatException, com.google.zxing.ChecksumException
        public override Result decodeRow(int rowNumber, BitArray row, IDictionary<DecodeHintType, object> hints)
        {
            int[] startPatternInfo = findStartPattern(row);
            int startCode = startPatternInfo[2];
            int codeSet;
            switch (startCode)
            {
              case CODE_START_A:
            codeSet = CODE_CODE_A;
            break;
              case CODE_START_B:
            codeSet = CODE_CODE_B;
            break;
              case CODE_START_C:
            codeSet = CODE_CODE_C;
            break;
              default:
            throw FormatException.FormatInstance;
            }

            bool done = false;
            bool isNextShifted = false;

            StringBuilder result = new StringBuilder(20);
            IList<sbyte> rawCodes = new List<sbyte>(20);

            int lastStart = startPatternInfo[0];
            int nextStart = startPatternInfo[1];
            int[] counters = new int[6];

            int lastCode = 0;
            int code = 0;
            int checksumTotal = startCode;
            int multiplier = 0;
            bool lastCharacterWasPrintable = true;

            while (!done)
            {

              bool unshift = isNextShifted;
              isNextShifted = false;

              // Save off last code
              lastCode = code;

              // Decode another code from image
              code = decodeCode(row, counters, nextStart);

              rawCodes.Add((sbyte) code);

              // Remember whether the last code was printable or not (excluding CODE_STOP)
              if (code != CODE_STOP)
              {
            lastCharacterWasPrintable = true;
              }

              // Add to checksum computation (if not CODE_STOP of course)
              if (code != CODE_STOP)
              {
            multiplier++;
            checksumTotal += multiplier * code;
              }

              // Advance to where the next code will to start
              lastStart = nextStart;
              foreach (int counter in counters)
              {
            nextStart += counter;
              }

              // Take care of illegal start codes
              switch (code)
              {
            case CODE_START_A:
            case CODE_START_B:
            case CODE_START_C:
              throw FormatException.FormatInstance;
              }

              switch (codeSet)
              {

            case CODE_CODE_A:
              if (code < 64)
              {
                result.Append((char)(' ' + code));
              }
              else if (code < 96)
              {
                result.Append((char)(code - 64));
              }
              else
              {
                // Don't let CODE_STOP, which always appears, affect whether whether we think the last
                // code was printable or not.
                if (code != CODE_STOP)
                {
                  lastCharacterWasPrintable = false;
                }
                switch (code)
                {
                  case CODE_FNC_1:
                  case CODE_FNC_2:
                  case CODE_FNC_3:
                  case CODE_FNC_4_A:
                    // do nothing?
                    break;
                  case CODE_SHIFT:
                    isNextShifted = true;
                    codeSet = CODE_CODE_B;
                    break;
                  case CODE_CODE_B:
                    codeSet = CODE_CODE_B;
                    break;
                  case CODE_CODE_C:
                    codeSet = CODE_CODE_C;
                    break;
                  case CODE_STOP:
                    done = true;
                    break;
                }
              }
              break;
            case CODE_CODE_B:
              if (code < 96)
              {
                result.Append((char)(' ' + code));
              }
              else
              {
                if (code != CODE_STOP)
                {
                  lastCharacterWasPrintable = false;
                }
                switch (code)
                {
                  case CODE_FNC_1:
                  case CODE_FNC_2:
                  case CODE_FNC_3:
                  case CODE_FNC_4_B:
                    // do nothing?
                    break;
                  case CODE_SHIFT:
                    isNextShifted = true;
                    codeSet = CODE_CODE_A;
                    break;
                  case CODE_CODE_A:
                    codeSet = CODE_CODE_A;
                    break;
                  case CODE_CODE_C:
                    codeSet = CODE_CODE_C;
                    break;
                  case CODE_STOP:
                    done = true;
                    break;
                }
              }
              break;
            case CODE_CODE_C:
              if (code < 100)
              {
                if (code < 10)
                {
                  result.Append('0');
                }
                result.Append(code);
              }
              else
              {
                if (code != CODE_STOP)
                {
                  lastCharacterWasPrintable = false;
                }
                switch (code)
                {
                  case CODE_FNC_1:
                    // do nothing?
                    break;
                  case CODE_CODE_A:
                    codeSet = CODE_CODE_A;
                    break;
                  case CODE_CODE_B:
                    codeSet = CODE_CODE_B;
                    break;
                  case CODE_STOP:
                    done = true;
                    break;
                }
              }
              break;
              }

              // Unshift back to another code set if we were shifted
              if (unshift)
              {
            codeSet = codeSet == CODE_CODE_A ? CODE_CODE_B : CODE_CODE_A;
              }

            }

            // Check for ample whitespace following pattern, but, to do this we first need to remember that
            // we fudged decoding CODE_STOP since it actually has 7 bars, not 6. There is a black bar left
            // to read off. Would be slightly better to properly read. Here we just skip it:
            nextStart = row.getNextUnset(nextStart);
            if (!row.isRange(nextStart, Math.Min(row.Size, nextStart + (nextStart - lastStart) / 2), false))
            {
              throw NotFoundException.NotFoundInstance;
            }

            // Pull out from sum the value of the penultimate check code
            checksumTotal -= multiplier * lastCode;
            // lastCode is the checksum then:
            if (checksumTotal % 103 != lastCode)
            {
              throw ChecksumException.ChecksumInstance;
            }

            // Need to pull out the check digits from string
            int resultLength = result.Length;
            if (resultLength == 0)
            {
              // false positive
              throw NotFoundException.NotFoundInstance;
            }

            // Only bother if the result had at least one character, and if the checksum digit happened to
            // be a printable character. If it was just interpreted as a control code, nothing to remove.
            if (resultLength > 0 && lastCharacterWasPrintable)
            {
              if (codeSet == CODE_CODE_C)
              {
            result.Remove(resultLength - 2, 2);
              }
              else
              {
            result.Remove(resultLength - 1, 1);
              }
            }

            float left = (float)(startPatternInfo[1] + startPatternInfo[0]) / 2.0f;
            float right = (float)(nextStart + lastStart) / 2.0f;

            int rawCodesSize = rawCodes.Count;
            sbyte[] rawBytes = new sbyte[rawCodesSize];
            for (int i = 0; i < rawCodesSize; i++)
            {
              rawBytes[i] = rawCodes[i];
            }

            return new Result(result.ToString(), rawBytes, new ResultPoint[]{new ResultPoint(left, (float) rowNumber), new ResultPoint(right, (float) rowNumber)}, BarcodeFormat.CODE_128);
        }