public override Result decodeRow(int rowNumber, BitArray row, System.Collections.Generic.Dictionary <Object,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 ReaderException.Instance;
}
bool done = false;
bool isNextShifted = false;
System.Text.StringBuilder result = new System.Text.StringBuilder(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);
// 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;
for (int i = 0; i < counters.Length; i++)
{
nextStart += counters[i];
}
// Take care of illegal start codes
switch (code)
{
case CODE_START_A:
case CODE_START_B:
case CODE_START_C:
throw ReaderException.Instance;
}
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_C;
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)
{
switch (codeSet)
{
case CODE_CODE_A:
codeSet = CODE_CODE_C;
break;
case CODE_CODE_B:
codeSet = CODE_CODE_A;
break;
case CODE_CODE_C:
codeSet = CODE_CODE_B;
break;
}
}
}
// 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:
int width = row.Size;
while (nextStart < width && row.get_Renamed(nextStart))
{
nextStart++;
}
if (!row.isRange(nextStart, System.Math.Min(width, nextStart + (nextStart - lastStart) / 2), false))
{
throw ReaderException.Instance;
}
// Pull out from sum the value of the penultimate check code
checksumTotal -= multiplier * lastCode;
// lastCode is the checksum then:
if (checksumTotal % 103 != lastCode)
{
throw ReaderException.Instance;
}
// Need to pull out the check digits from string
int resultLength = result.Length;
// 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, resultLength - (resultLength - 2));
}
else
{
result.Remove(resultLength - 1, resultLength - (resultLength - 1));
}
}
System.String resultString = result.ToString();
if (resultString.Length == 0)
{
// Almost surely a false positive
throw ReaderException.Instance;
}
//UPGRADE_WARNING: Data types in Visual C# might be different. Verify the accuracy of narrowing conversions. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1042'"
float left = (float) (startPatternInfo[1] + startPatternInfo[0]) / 2.0f;
//UPGRADE_WARNING: Data types in Visual C# might be different. Verify the accuracy of narrowing conversions. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1042'"
float right = (float) (nextStart + lastStart) / 2.0f;
//UPGRADE_WARNING: Data types in Visual C# might be different. Verify the accuracy of narrowing conversions. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1042'"
return new Result(resultString, null, new ResultPoint[]{new ResultPoint(left, (float) rowNumber), new ResultPoint(right, (float) rowNumber)}, BarcodeFormat.CODE_128);
}
private static int[] findStartPattern(BitArray row)
{
int width = row.Size;
int rowOffset = 0;
while (rowOffset < width)
{
if (row.get_Renamed(rowOffset))
{
break;
}
rowOffset++;
}
int counterPosition = 0;
int[] counters = new int[6];
int patternStart = rowOffset;
bool isWhite = false;
int patternLength = counters.Length;
for (int i = rowOffset; i < width; i++)
{
bool pixel = row.get_Renamed(i);
if (pixel ^ isWhite)
{
counters[counterPosition]++;
}
else
{
if (counterPosition == patternLength - 1)
{
int bestVariance = MAX_AVG_VARIANCE;
int bestMatch = - 1;
for (int startCode = CODE_START_A; startCode <= CODE_START_C; startCode++)
{
int variance = patternMatchVariance(counters, CODE_PATTERNS[startCode], MAX_INDIVIDUAL_VARIANCE);
if (variance < bestVariance)
{
bestVariance = variance;
bestMatch = startCode;
}
}
if (bestMatch >= 0)
{
// Look for whitespace before start pattern, >= 50% of width of start pattern
if (row.isRange(System.Math.Max(0, patternStart - (i - patternStart) / 2), patternStart, false))
{
return new int[]{patternStart, i, bestMatch};
}
}
patternStart += counters[0] + counters[1];
for (int y = 2; y < patternLength; y++)
{
counters[y - 2] = counters[y];
}
counters[patternLength - 2] = 0;
counters[patternLength - 1] = 0;
counterPosition--;
}
else
{
counterPosition++;
}
counters[counterPosition] = 1;
isWhite = !isWhite;
}
}
throw ReaderException.Instance;
}
internal static int[] findStartGuardPattern(BitArray row)
{
bool foundStart = false;
int[] startRange = null;
int nextStart = 0;
while (!foundStart)
{
startRange = findGuardPattern(row, nextStart, false, START_END_PATTERN);
int start = startRange[0];
nextStart = startRange[1];
// Make sure there is a quiet zone at least as big as the start pattern before the barcode.
// If this check would run off the left edge of the image, do not accept this barcode,
// as it is very likely to be a false positive.
int quietStart = start - (nextStart - start);
if (quietStart >= 0)
{
foundStart = row.isRange(quietStart, start, false);
}
}
return startRange;
}
private static int[] findAsteriskPattern(BitArray row)
{
int width = row.Size;
int rowOffset = 0;
while (rowOffset < width)
{
if (row.get_Renamed(rowOffset))
{
break;
}
rowOffset++;
}
int counterPosition = 0;
int[] counters = new int[9];
int patternStart = rowOffset;
bool isWhite = false;
int patternLength = counters.Length;
for (int i = rowOffset; i < width; i++)
{
bool pixel = row.get_Renamed(i);
if (pixel ^ isWhite)
{
counters[counterPosition]++;
}
else
{
if (counterPosition == patternLength - 1)
{
if (toNarrowWidePattern(counters) == ASTERISK_ENCODING)
{
// Look for whitespace before start pattern, >= 50% of width of start pattern
if (row.isRange(System.Math.Max(0, patternStart - (i - patternStart) / 2), patternStart, false))
{
return new int[]{patternStart, i};
}
}
patternStart += counters[0] + counters[1];
for (int y = 2; y < patternLength; y++)
{
counters[y - 2] = counters[y];
}
counters[patternLength - 2] = 0;
counters[patternLength - 1] = 0;
counterPosition--;
}
else
{
counterPosition++;
}
counters[counterPosition] = 1;
isWhite = !isWhite;
}
}
throw ReaderException.Instance;
}
/// <summary> <p>Like {@link #decodeRow(int, BitArray, java.util.Hashtable)}, but
/// allows caller to inform method about where the UPC/EAN start pattern is
/// found. This allows this to be computed once and reused across many implementations.</p>
/// </summary>
public virtual Result decodeRow(int rowNumber, BitArray row, int[] startGuardRange, System.Collections.Generic.Dictionary <Object,Object> hints)
{
ResultPointCallback resultPointCallback = (hints != null && hints.ContainsKey(DecodeHintType.NEED_RESULT_POINT_CALLBACK))?(ResultPointCallback) hints[DecodeHintType.NEED_RESULT_POINT_CALLBACK]:null; //Upgrade: Fixed issue with dictionary
if (resultPointCallback != null)
{
resultPointCallback.foundPossibleResultPoint(new ResultPoint((startGuardRange[0] + startGuardRange[1]) / 2.0f, rowNumber));
}
System.Text.StringBuilder result = decodeRowStringBuffer;
result.Length = 0;
int endStart = decodeMiddle(row, startGuardRange, result);
if (resultPointCallback != null)
{
resultPointCallback.foundPossibleResultPoint(new ResultPoint(endStart, rowNumber));
}
int[] endRange = decodeEnd(row, endStart);
if (resultPointCallback != null)
{
resultPointCallback.foundPossibleResultPoint(new ResultPoint((endRange[0] + endRange[1]) / 2.0f, rowNumber));
}
// Make sure there is a quiet zone at least as big as the end pattern after the barcode. The
// spec might want more whitespace, but in practice this is the maximum we can count on.
int end = endRange[1];
int quietEnd = end + (end - endRange[0]);
if (quietEnd >= row.Size || !row.isRange(end, quietEnd, false))
{
throw ReaderException.Instance;
}
System.String resultString = result.ToString();
if (!checkChecksum(resultString))
{
throw ReaderException.Instance;
}
//UPGRADE_WARNING: Data types in Visual C# might be different. Verify the accuracy of narrowing conversions. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1042'"
float left = (float) (startGuardRange[1] + startGuardRange[0]) / 2.0f;
//UPGRADE_WARNING: Data types in Visual C# might be different. Verify the accuracy of narrowing conversions. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1042'"
float right = (float) (endRange[1] + endRange[0]) / 2.0f;
//UPGRADE_WARNING: Data types in Visual C# might be different. Verify the accuracy of narrowing conversions. "ms-help://MS.VSCC.v80/dv_commoner/local/redirect.htm?index='!DefaultContextWindowIndex'&keyword='jlca1042'"
return new Result(resultString, null, new ResultPoint[]{new ResultPoint(left, (float) rowNumber), new ResultPoint(right, (float) rowNumber)}, BarcodeFormat);
}
