public BitArray getBlackColumn(int x, BitArray column, int startY, int getHeight)
{
if (column == null || column.getSize() < getHeight)
{
column = new BitArray(getHeight);
}
else
{
column.clear();
}
// Reuse the same int array each time
initLuminances();
luminances = getLuminanceColumn(x, luminances);
// We don't handle "row sampling" specially here
for (int y = 0; y < getHeight; y++)
{
if (luminances[startY + y] < blackPoint)
{
column.set(y);
}
}
return(column);
}
public BitArray getBlackRow(int y, BitArray row, int startX, int getWidth) {
if (row == null || row.getSize() < getWidth) {
row = new BitArray(getWidth);
} else {
row.clear();
}
// Reuse the same int array each time
initLuminances();
luminances = getLuminanceRow(y, luminances);
// If the current decoder calculated the blackPoint based on one row, assume we're trying to
// decode a 1D barcode, and apply some sharpening.
if (lastMethod.Equals(BlackPointEstimationMethod.ROW_SAMPLING)) {
int left = luminances[startX];
int center = luminances[startX + 1];
for (int x = 1; x < getWidth - 1; x++) {
int right = luminances[startX + x + 1];
// Simple -1 4 -1 box filter with a weight of 2
int luminance = ((center << 2) - left - right) >> 1;
if (luminance < blackPoint) {
row.set(x);
}
left = center;
center = right;
}
} else {
for (int x = 0; x < getWidth; x++) {
if (luminances[startX + x] < blackPoint) {
row.set(x);
}
}
}
return row;
}
protected override int decodeMiddle(BitArray row, int[] startRange, StringBuilder result)
{
int[] counters = decodeMiddleCounters;
counters[0] = 0;
counters[1] = 0;
counters[2] = 0;
counters[3] = 0;
int end = row.getSize();
int rowOffset = startRange[1];
for (int x = 0; x < 4 && rowOffset < end; x++) {
int bestMatch = decodeDigit(row, counters, rowOffset, L_PATTERNS);
result.Append((char) ('0' + bestMatch));
for (int i = 0; i < counters.Length; i++) {
rowOffset += counters[i];
}
}
int[] middleRange = findGuardPattern(row, rowOffset, true, MIDDLE_PATTERN);
rowOffset = middleRange[1];
for (int x = 0; x < 4 && rowOffset < end; x++) {
int bestMatch = decodeDigit(row, counters, rowOffset, L_PATTERNS);
result.Append((char) ('0' + bestMatch));
for (int i = 0; i < counters.Length; i++) {
rowOffset += counters[i];
}
}
return rowOffset;
}
public BitArray getBlackRow(int y, BitArray row, int startX, int getWidth)
{
if (row == null || row.getSize() < getWidth)
{
row = new BitArray(getWidth);
}
else
{
row.clear();
}
// Reuse the same int array each time
initLuminances();
luminances = getLuminanceRow(y, luminances);
// If the current decoder calculated the blackPoint based on one row, assume we're trying to
// decode a 1D barcode, and apply some sharpening.
if (lastMethod.Equals(BlackPointEstimationMethod.ROW_SAMPLING))
{
int left = luminances[startX];
int center = luminances[startX + 1];
for (int x = 1; x < getWidth - 1; x++)
{
int right = luminances[startX + x + 1];
// Simple -1 4 -1 box filter with a weight of 2
int luminance = ((center << 2) - left - right) >> 1;
if (luminance < blackPoint)
{
row.set(x);
}
left = center;
center = right;
}
}
else
{
for (int x = 0; x < getWidth; x++)
{
if (luminances[startX + x] < blackPoint)
{
row.set(x);
}
}
}
return(row);
}
protected override int decodeMiddle(BitArray row, int[] startRange, StringBuilder resultString) {
int[] counters = decodeMiddleCounters;
counters[0] = 0;
counters[1] = 0;
counters[2] = 0;
counters[3] = 0;
int end = row.getSize();
int rowOffset = startRange[1];
int lgPatternFound = 0;
for (int x = 0; x < 6 && rowOffset < end; x++) {
int bestMatch = decodeDigit(row, counters, rowOffset, L_AND_G_PATTERNS);
resultString.Append((char) ('0' + bestMatch % 10));
for (int i = 0; i < counters.Length; i++) {
rowOffset += counters[i];
}
if (bestMatch >= 10) {
lgPatternFound |= 1 << (5 - x);
}
}
determineFirstDigit(resultString, lgPatternFound);
int[] middleRange = findGuardPattern(row, rowOffset, true, MIDDLE_PATTERN);
rowOffset = middleRange[1];
for (int x = 0; x < 6 && rowOffset < end; x++) {
int bestMatch = decodeDigit(row, counters, rowOffset, L_PATTERNS);
resultString.Append((char) ('0' + bestMatch));
for (int i = 0; i < counters.Length; i++) {
rowOffset += counters[i];
}
}
return rowOffset;
}
/**
* Skip all whitespace until we get to the first black line.
*
* @param row row of black/white values to search
* @return index of the first black line.
* @throws ReaderException Throws exception if no black lines are found in the row
*/
private int skipWhiteSpace(BitArray row)
{
int width = row.getSize();
int endStart = 0;
while (endStart < width) {
if (row.get(endStart)) {
break;
}
endStart++;
}
if (endStart == width) {
throw new ReaderException();
}
return endStart;
}
/**
* @param row row of black/white values to search
* @param rowOffset position to start search
* @param pattern pattern of counts of number of black and white pixels that are
* being searched for as a pattern
* @return start/end horizontal offset of guard pattern, as an array of two
* ints
* @throws ReaderException if pattern is not found
*/
int[] findGuardPattern(BitArray row, int rowOffset, int[] pattern)
{
// TODO: This is very similar to implementation in AbstractUPCEANReader. Consider if they can be merged to
// a single method.
int patternLength = pattern.Length;
int[] counters = new int[patternLength];
int width = row.getSize();
bool isWhite = false;
int counterPosition = 0;
int patternStart = rowOffset;
for (int x = rowOffset; x < width; x++) {
bool pixel = row.get(x);
if ((!pixel && isWhite) || (pixel && !isWhite)) {
counters[counterPosition]++;
} else {
if (counterPosition == patternLength - 1) {
if (patternMatchVariance(counters, pattern, MAX_INDIVIDUAL_VARIANCE) < MAX_AVG_VARIANCE) {
return new int[]{patternStart, x};
}
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 new ReaderException();
}
/**
* Identify where the end of the middle / payload section ends.
*
* @param row row of black/white values to search
* @return Array, containing index of start of 'end block' and end of 'end
* block'
* @throws ReaderException
*/
int[] decodeEnd(BitArray row)
{
// For convenience, reverse the row and then
// search from 'the start' for the end block
row.reverse();
int endStart = skipWhiteSpace(row);
int[] endPattern;
try {
endPattern = findGuardPattern(row, endStart, END_PATTERN_REVERSED);
} catch (ReaderException e) {
// Put our row of data back the right way before throwing
row.reverse();
throw e;
}
// The start & end patterns must be pre/post fixed by a quiet zone. This
// zone must be at least 10 times the width of a narrow line.
// ref: http://www.barcode-1.net/i25code.html
validateQuietZone(row, endPattern[0]);
// Now recalc the indicies of where the 'endblock' starts & stops to
// accomodate
// the reversed nature of the search
int temp = endPattern[0];
endPattern[0] = row.getSize() - endPattern[1];
endPattern[1] = row.getSize() - temp;
// Put the row back the righ way.
row.reverse();
return endPattern;
}
public Result decodeRow(int rowNumber, BitArray row, int[] startGuardRange)
{
StringBuilder result = decodeRowStringBuffer;
result.Length = 0;
int endStart = decodeMiddle(row, startGuardRange, result);
int[] endRange = decodeEnd(row, endStart);
// 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.getSize() || !row.isRange(end, quietEnd, false)) {
throw new ReaderException();
}
String resultString = result.ToString();
if (!checkChecksum(resultString)) {
throw new ReaderException();
}
float left = (float) (startGuardRange[1] + startGuardRange[0]) / 2.0f;
float right = (float) (endRange[1] + endRange[0]) / 2.0f;
return new Result(resultString,
null, // no natural byte representation for these barcodes
new ResultPoint[]{
new GenericResultPoint(left, (float) rowNumber),
new GenericResultPoint(right, (float) rowNumber)},
getBarcodeFormat());
}
/**
* @param row row of black/white values to search
* @param rowOffset position to start search
* @param whiteFirst if true, indicates that the pattern specifies white/black/white/...
* pixel counts, otherwise, it is interpreted as black/white/black/...
* @param pattern pattern of counts of number of black and white pixels that are being
* searched for as a pattern
* @return start/end horizontal offset of guard pattern, as an array of two ints
* @throws ReaderException if pattern is not found
*/
public static int[] findGuardPattern(BitArray row, int rowOffset, bool whiteFirst, int[] pattern)
{
int patternLength = pattern.Length;
int[] counters = new int[patternLength];
int width = row.getSize();
bool isWhite = false;
while (rowOffset < width) {
isWhite = !row.get(rowOffset);
if (whiteFirst == isWhite) {
break;
}
rowOffset++;
}
int counterPosition = 0;
int patternStart = rowOffset;
for (int x = rowOffset; x < width; x++) {
bool pixel = row.get(x);
if ((!pixel && isWhite) || (pixel && !isWhite)) {
counters[counterPosition]++;
} else {
if (counterPosition == patternLength - 1) {
if (patternMatchVariance(counters, pattern, MAX_INDIVIDUAL_VARIANCE) < MAX_AVG_VARIANCE) {
return new int[]{patternStart, x};
}
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 new ReaderException();
}
/**
* Records the size of successive runs of white and black pixels in a row, starting at a given point.
* The values are recorded in the given array, and the number of runs recorded is equal to the size
* of the array. If the row starts on a white pixel at the given start point, then the first count
* recorded is the run of white pixels starting from that point; likewise it is the count of a run
* of black pixels if the row begin on a black pixels at that point.
*
* @param row row to count from
* @param start offset into row to start at
* @param counters array into which to record counts
* @throws ReaderException if counters cannot be filled entirely from row before running out of pixels
*/
public static void recordPattern(BitArray row, int start, int[] counters)
{
int numCounters = counters.Length;
for (int i = 0; i < numCounters; i++) {
counters[i] = 0;
}
int end = row.getSize();
if (start >= end) {
throw new ReaderException();
}
bool isWhite = !row.get(start);
int counterPosition = 0;
int k = start;
while (k < end) {
bool pixel = row.get(k);
if ((!pixel && isWhite) || (pixel && !isWhite)) {
counters[counterPosition]++;
} else {
counterPosition++;
if (counterPosition == numCounters) {
break;
} else {
counters[counterPosition] = 1;
isWhite = !isWhite;
}
}
k++;
}
// If we read fully the last section of pixels and filled up our counters -- or filled
// the last counter but ran off the side of the image, OK. Otherwise, a problem.
if (!(counterPosition == numCounters || (counterPosition == numCounters - 1 && k == end))) {
throw new ReaderException();
}
}
public override Result decodeRow(int rowNumber, BitArray row, System.Collections.Hashtable 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 new ReaderException();
}
bool done = false;
bool isNextShifted = false;
StringBuilder result = new StringBuilder();
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 new ReaderException();
}
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 whitespice 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:
while (row.get(nextStart)) {
nextStart++;
}
if (!row.isRange(nextStart, Math.Min(row.getSize(), nextStart + (nextStart - lastStart) / 2), false)) {
throw new ReaderException();
}
// Pull out from sum the value of the penultimate check code
checksumTotal -= multiplier * lastCode;
// lastCode is the checksum then:
if (checksumTotal % 103 != lastCode) {
throw new ReaderException();
}
// Need to pull out the check digits from string
int resultLength = result.Length;
// Only bother if, well, 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);
}
}
String resultString = result.ToString();
if (resultString.Length == 0) {
// Almost surely a false positive
throw new ReaderException();
}
float left = (float) (startPatternInfo[1] + startPatternInfo[0]) / 2.0f;
float right = (float) (nextStart + lastStart) / 2.0f;
return new Result(
resultString,
null,
new ResultPoint[]{
new GenericResultPoint(left, (float) rowNumber),
new GenericResultPoint(right, (float) rowNumber)},
BarcodeFormat.CODE_128);
}
private static int[] findStartPattern(BitArray row) {
int width = row.getSize();
int rowOffset = 0;
while (rowOffset < width) {
if (row.get(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(i);
if ((!pixel && isWhite) || (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(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 new ReaderException();
}
public BitArray getBlackColumn(int x, BitArray column, int startY, int getHeight) {
if (column == null || column.getSize() < getHeight) {
column = new BitArray(getHeight);
} else {
column.clear();
}
// Reuse the same int array each time
initLuminances();
luminances = getLuminanceColumn(x, luminances);
// We don't handle "row sampling" specially here
for (int y = 0; y < getHeight; y++) {
if (luminances[startY + y] < blackPoint) {
column.set(y);
}
}
return column;
}
public override Result decodeRow(int rowNumber, BitArray row, System.Collections.Hashtable hints) {
int[] start = findAsteriskPattern(row);
int nextStart = start[1];
int end = row.getSize();
// Read off white space
while (nextStart < end && !row.get(nextStart)) {
nextStart++;
}
StringBuilder result = new StringBuilder();
int[] counters = new int[9];
char decodedChar;
int lastStart;
do {
recordPattern(row, nextStart, counters);
int pattern = toNarrowWidePattern(counters);
decodedChar = patternToChar(pattern);
result.Append(decodedChar);
lastStart = nextStart;
for (int i = 0; i < counters.Length; i++) {
nextStart += counters[i];
}
// Read off white space
while (nextStart < end && !row.get(nextStart)) {
nextStart++;
}
} while (decodedChar != '*');
result.Remove(result.Length - 1, 1); // remove asterisk
// Look for whitespace after pattern:
int lastPatternSize = 0;
for (int i = 0; i < counters.Length; i++) {
lastPatternSize += counters[i];
}
int whiteSpaceAfterEnd = nextStart - lastStart - lastPatternSize;
// If 50% of last pattern size, following last pattern, is not whitespace, fail
// (but if it's whitespace to the very end of the image, that's OK)
if (nextStart != end && whiteSpaceAfterEnd / 2 < lastPatternSize) {
throw new ReaderException();
}
if (usingCheckDigit) {
int max = result.Length - 1;
int total = 0;
for (int i = 0; i < max; i++) {
total += ALPHABET_STRING.IndexOf(result[i]);
}
if (total % 43 != ALPHABET_STRING.IndexOf(result[max]))
{
throw new ReaderException();
}
result.Remove(max,1);
}
String resultString = result.ToString();
if (extendedMode) {
resultString = decodeExtended(resultString);
}
if (resultString.Length == 0) {
// Almost surely a false positive
throw new ReaderException();
}
float left = (float) (start[1] + start[0]) / 2.0f;
float right = (float) (nextStart + lastStart) / 2.0f;
return new Result(
resultString,
null,
new ResultPoint[]{
new GenericResultPoint(left, (float) rowNumber),
new GenericResultPoint(right, (float) rowNumber)},
BarcodeFormat.CODE_39);
}
private static int[] findAsteriskPattern(BitArray row) {
int width = row.getSize();
int rowOffset = 0;
while (rowOffset < width) {
if (row.get(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(i);
if ((!pixel && isWhite) || (pixel && !isWhite)) {
counters[counterPosition]++;
} else {
if (counterPosition == patternLength - 1) {
try {
if (toNarrowWidePattern(counters) == ASTERISK_ENCODING) {
// Look for whitespace before start pattern, >= 50% of width of start pattern
if (row.isRange(Math.Max(0, patternStart - (i - patternStart) / 2), patternStart, false)) {
return new int[]{patternStart, i};
}
}
} catch (ReaderException re) {
// no match, continue
}
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 new ReaderException();
}
