* ITFReader.cpp
* ZXing
*
- * Created by Lukasz Warchol on 10-01-26.
* Copyright 2010 ZXing authors All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
#include <math.h>
namespace zxing {
- namespace oned {
-
- static const int W = 3; // Pixel width of a wide line
- static const int N = 1; // Pixed width of a narrow line
-
- const int DEFAULT_ALLOWED_LENGTHS[4] = { 6, 10, 14, 44 };
-
- /**
- * Start/end guard pattern.
- *
- * Note: The end pattern is reversed because the row is reversed before
- * searching for the END_PATTERN
- */
- static const int START_PATTERN_LEN = 4;
- static const int START_PATTERN[START_PATTERN_LEN] = {N, N, N, N};
-
- static const int END_PATTERN_REVERSED_LEN = 3;
- static const int END_PATTERN_REVERSED[END_PATTERN_REVERSED_LEN] = {N, N, W};
-
- /**
- * Patterns of Wide / Narrow lines to indicate each digit
- */
- static const int PATTERNS_LEN = 10;
- static const int PATTERNS[PATTERNS_LEN][5] = {
- {N, N, W, W, N}, // 0
- {W, N, N, N, W}, // 1
- {N, W, N, N, W}, // 2
- {W, W, N, N, N}, // 3
- {N, N, W, N, W}, // 4
- {W, N, W, N, N}, // 5
- {N, W, W, N, N}, // 6
- {N, N, N, W, W}, // 7
- {W, N, N, W, N}, // 8
- {N, W, N, W, N} // 9
- };
-
-
- ITFReader::ITFReader(){
- narrowLineWidth = -1;
- }
-
-
- Ref<Result> ITFReader::decodeRow(int rowNumber, Ref<BitArray> row){
- // Find out where the Middle section (payload) starts & ends
- int* startRange = decodeStart(row);
- int* endRange = decodeEnd(row);
-
- std::string tmpResult;
- decodeMiddle(row, startRange[1], endRange[0], tmpResult);
-
- // To avoid false positives with 2D barcodes (and other patterns), make
- // an assumption that the decoded string must be 6, 10 or 14 digits.
- int length = tmpResult.length();
- bool lengthOK = false;
- if (length == 6 || length == 10 || length == 14) {
- lengthOK = true;
- }
- if (!lengthOK) {
- throw ReaderException("not enought characters count");
- }
-
- Ref<String> resultString(new String(tmpResult));
-
- std::vector< Ref<ResultPoint> > resultPoints(2);
- Ref<OneDResultPoint> resultPoint1(new OneDResultPoint(startRange[1], (float) rowNumber));
- Ref<OneDResultPoint> resultPoint2(new OneDResultPoint(endRange[0], (float) rowNumber));
- resultPoints[0] = resultPoint1;
- resultPoints[1] = resultPoint2;
-
- ArrayRef<unsigned char> resultBytes(1);
-
- delete [] startRange;
- delete [] endRange;
-
- Ref<Result> res(new Result(resultString, resultBytes, resultPoints, BarcodeFormat_ITF));
- return res;
- }
-
- /**
- * @param row row of black/white values to search
- * @param payloadStart offset of start pattern
- * @param resultString {@link StringBuffer} to append decoded chars to
- * @throws ReaderException if decoding could not complete successfully
- */
- void ITFReader::decodeMiddle(Ref<BitArray> row, int payloadStart, int payloadEnd, std::string& resultString){
- // Digits are interleaved in pairs - 5 black lines for one digit, and the
- // 5
- // interleaved white lines for the second digit.
- // Therefore, need to scan 10 lines and then
- // split these into two arrays
- int counterDigitPairLen = 10;
- int* counterDigitPair = new int[counterDigitPairLen];
- for (int i=0; i<counterDigitPairLen; i++) {
- counterDigitPair[i] = 0;
- }
-
- int* counterBlack = new int[5];
- int* counterWhite = new int[5];
- for (int i=0; i<5; i++) {
- counterBlack[i] = 0;
- counterWhite[i] = 0;
- }
-
- while (payloadStart < payloadEnd) {
- // Get 10 runs of black/white.
- recordPattern(row, payloadStart, counterDigitPair, counterDigitPairLen);
- // Split them into each array
- for (int k = 0; k < 5; k++) {
- int twoK = k << 1;
- counterBlack[k] = counterDigitPair[twoK];
- counterWhite[k] = counterDigitPair[twoK + 1];
- }
-
- int bestMatch = decodeDigit(counterBlack, 5);
- resultString.append(1, (char) ('0' + bestMatch));
- bestMatch = decodeDigit(counterWhite, 5);
- resultString.append(1, (char) ('0' + bestMatch));
-
- for (int i = 0; i < counterDigitPairLen; i++) {
- payloadStart += counterDigitPair[i];
- }
- }
- delete [] counterDigitPair;
- delete [] counterBlack;
- delete [] counterWhite;
- }
-
- /**
- * Identify where the start of the middle / payload section starts.
- *
- * @param row row of black/white values to search
- * @return Array, containing index of start of 'start block' and end of
- * 'start block'
- * @throws ReaderException
- */
- int* ITFReader::decodeStart(Ref<BitArray> row){
- int endStart = skipWhiteSpace(row);
-/// static int* findGuardPattern(Ref<BitArray> row, int rowOffset, bool whiteFirst, const int pattern[], int patternLen);
- int* startPattern = findGuardPattern(row, endStart, START_PATTERN, START_PATTERN_LEN);
-
- // Determine the width of a narrow line in pixels. We can do this by
- // getting the width of the start pattern and dividing by 4 because its
- // made up of 4 narrow lines.
- narrowLineWidth = (startPattern[1] - startPattern[0]) >> 2;
-
- validateQuietZone(row, startPattern[0]);
-
- return startPattern;
- }
-
- /**
- * 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* ITFReader::decodeEnd(Ref<BitArray> row){
- // For convenience, reverse the row and then
- // search from 'the start' for the end block
- row->reverse();
- try {
- int endStart = skipWhiteSpace(row);
- int* endPattern = findGuardPattern(row, endStart, END_PATTERN_REVERSED, END_PATTERN_REVERSED_LEN);
-
- // 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 recalculate the indices of where the 'endblock' starts & stops to
- // accommodate
- // the reversed nature of the search
- int temp = endPattern[0];
- endPattern[0] = row->getSize() - endPattern[1];
- endPattern[1] = row->getSize() - temp;
-
- return endPattern;
- }catch (Exception e) {
- 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. Scan back until
- * we either get to the start of the barcode or match the necessary number of
- * quiet zone pixels.
- *
- * Note: Its assumed the row is reversed when using this method to find
- * quiet zone after the end pattern.
- *
- * ref: http://www.barcode-1.net/i25code.html
- *
- * @param row bit array representing the scanned barcode.
- * @param startPattern index into row of the start or end pattern.
- * @throws ReaderException if the quiet zone cannot be found, a ReaderException is thrown.
- */
- void ITFReader::validateQuietZone(Ref<BitArray> row, int startPattern){
-#pragma mark needs some corrections
-// int quietCount = narrowLineWidth * 10; // expect to find this many pixels of quiet zone
-//
-// for (int i = startPattern - 1; quietCount > 0 && i >= 0; i--) {
-// if (row->get(i)) {
-// break;
-// }
-// quietCount--;
-// }
-// if (quietCount != 0) {
-// // Unable to find the necessary number of quiet zone pixels.
-// throw ReaderException("Unable to find the necessary number of quiet zone pixels");
-// }
- }
-
- /**
- * 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
- */
- int ITFReader::skipWhiteSpace(Ref<BitArray> row){
- int width = row->getSize();
- int endStart = 0;
- while (endStart < width) {
- if (row->get(endStart)) {
- break;
- }
- endStart++;
- }
- if (endStart == width) {
- throw 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* ITFReader::findGuardPattern(Ref<BitArray> row, int rowOffset, const int pattern[], int patternLen){
- // TODO: This is very similar to implementation in UPCEANReader. Consider if they can be
- // merged to a single method.
- int patternLength = patternLen;
- int* counters = new int[patternLength];
- for (int i=0; i<patternLength; i++) {
- counters[i] = 0;
- }
- 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) {
- counters[counterPosition]++;
- } else {
- if (counterPosition == patternLength - 1) {
- if (patternMatchVariance(counters, patternLength, pattern, MAX_INDIVIDUAL_VARIANCE) < MAX_AVG_VARIANCE) {
- int* resultValue = new int[2];
- resultValue[0] = patternStart;
- resultValue[1] = x;
- return resultValue;
- }
- 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("");
- }
-
- /**
- * Attempts to decode a sequence of ITF black/white lines into single
- * digit.
- *
- * @param counters the counts of runs of observed black/white/black/... values
- * @return The decoded digit
- * @throws ReaderException if digit cannot be decoded
- */
- int ITFReader::decodeDigit(int counters[], int countersLen){
- int bestVariance = MAX_AVG_VARIANCE; // worst variance we'll accept
- int bestMatch = -1;
- int max = PATTERNS_LEN;
- for (int i = 0; i < max; i++) {
- int pattern[countersLen];
- for(int ind = 0; ind<countersLen; ind++){
- pattern[ind] = PATTERNS[i][ind];
- }
- int variance = patternMatchVariance(counters, countersLen, pattern, MAX_INDIVIDUAL_VARIANCE);
- if (variance < bestVariance) {
- bestVariance = variance;
- bestMatch = i;
- }
- }
- if (bestMatch >= 0) {
- return bestMatch;
- } else {
- throw ReaderException("digit didint found");
- }
- }
-
-
- ITFReader::~ITFReader(){
- }
- }
+ namespace oned {
+
+ static const int W = 3; // Pixel width of a wide line
+ static const int N = 1; // Pixed width of a narrow line
+
+ const int DEFAULT_ALLOWED_LENGTHS[4] = { 6, 10, 14, 44 };
+
+ /**
+ * Start/end guard pattern.
+ *
+ * Note: The end pattern is reversed because the row is reversed before
+ * searching for the END_PATTERN
+ */
+ static const int START_PATTERN_LEN = 4;
+ static const int START_PATTERN[START_PATTERN_LEN] = {N, N, N, N};
+
+ static const int END_PATTERN_REVERSED_LEN = 3;
+ static const int END_PATTERN_REVERSED[END_PATTERN_REVERSED_LEN] = {N, N, W};
+
+ /**
+ * Patterns of Wide / Narrow lines to indicate each digit
+ */
+ static const int PATTERNS_LEN = 10;
+ static const int PATTERNS[PATTERNS_LEN][5] = {
+ {N, N, W, W, N}, // 0
+ {W, N, N, N, W}, // 1
+ {N, W, N, N, W}, // 2
+ {W, W, N, N, N}, // 3
+ {N, N, W, N, W}, // 4
+ {W, N, W, N, N}, // 5
+ {N, W, W, N, N}, // 6
+ {N, N, N, W, W}, // 7
+ {W, N, N, W, N}, // 8
+ {N, W, N, W, N} // 9
+ };
+
+
+ ITFReader::ITFReader() : narrowLineWidth(-1) {
+ }
+
+
+ Ref<Result> ITFReader::decodeRow(int rowNumber, Ref<BitArray> row) {
+ int* startRange = 0;
+ int* endRange = 0;
+ try {
+ // Find out where the Middle section (payload) starts & ends
+ startRange = decodeStart(row);
+ endRange = decodeEnd(row);
+
+ std::string tmpResult;
+ decodeMiddle(row, startRange[1], endRange[0], tmpResult);
+
+ // To avoid false positives with 2D barcodes (and other patterns), make
+ // an assumption that the decoded string must be 6, 10 or 14 digits.
+ int length = tmpResult.length();
+ bool lengthOK = false;
+ if (length == 6 || length == 10 || length == 14) {
+ lengthOK = true;
+ }
+ if (!lengthOK) {
+ throw ReaderException("not enough characters count");
+ }
+
+ Ref<String> resultString(new String(tmpResult));
+
+ std::vector< Ref<ResultPoint> > resultPoints(2);
+ Ref<OneDResultPoint> resultPoint1(new OneDResultPoint(startRange[1], (float) rowNumber));
+ Ref<OneDResultPoint> resultPoint2(new OneDResultPoint(endRange[0], (float) rowNumber));
+ resultPoints[0] = resultPoint1;
+ resultPoints[1] = resultPoint2;
+
+ delete [] startRange;
+ delete [] endRange;
+ ArrayRef<unsigned char> resultBytes(1);
+ return Ref<Result>(new Result(resultString, resultBytes, resultPoints, BarcodeFormat_ITF));
+ } catch (ReaderException re) {
+ delete [] startRange;
+ delete [] endRange;
+ return Ref<Result>();
+ }
+ }
+
+ /**
+ * @param row row of black/white values to search
+ * @param payloadStart offset of start pattern
+ * @param resultString {@link StringBuffer} to append decoded chars to
+ * @throws ReaderException if decoding could not complete successfully
+ */
+ void ITFReader::decodeMiddle(Ref<BitArray> row, int payloadStart, int payloadEnd,
+ std::string& resultString) {
+ // Digits are interleaved in pairs - 5 black lines for one digit, and the
+ // 5
+ // interleaved white lines for the second digit.
+ // Therefore, need to scan 10 lines and then
+ // split these into two arrays
+ int counterDigitPairLen = 10;
+ int counterDigitPair[counterDigitPairLen];
+ for (int i=0; i<counterDigitPairLen; i++) {
+ counterDigitPair[i] = 0;
+ }
+
+ int counterBlack[5];
+ int counterWhite[5];
+ for (int i=0; i<5; i++) {
+ counterBlack[i] = 0;
+ counterWhite[i] = 0;
+ }
+
+ while (payloadStart < payloadEnd) {
+ // Get 10 runs of black/white.
+ if (!recordPattern(row, payloadStart, counterDigitPair, counterDigitPairLen)) {
+ throw ReaderException("");
+ }
+ // Split them into each array
+ for (int k = 0; k < 5; k++) {
+ int twoK = k << 1;
+ counterBlack[k] = counterDigitPair[twoK];
+ counterWhite[k] = counterDigitPair[twoK + 1];
+ }
+
+ int bestMatch = decodeDigit(counterBlack, 5);
+ resultString.append(1, (char) ('0' + bestMatch));
+ bestMatch = decodeDigit(counterWhite, 5);
+ resultString.append(1, (char) ('0' + bestMatch));
+
+ for (int i = 0; i < counterDigitPairLen; i++) {
+ payloadStart += counterDigitPair[i];
+ }
+ }
+ }
+
+ /**
+ * Identify where the start of the middle / payload section starts.
+ *
+ * @param row row of black/white values to search
+ * @return Array, containing index of start of 'start block' and end of
+ * 'start block'
+ * @throws ReaderException
+ */
+ int* ITFReader::decodeStart(Ref<BitArray> row) {
+ int endStart = skipWhiteSpace(row);
+ int* startPattern = 0;
+ try {
+ startPattern = findGuardPattern(row, endStart, START_PATTERN, START_PATTERN_LEN);
+
+ // Determine the width of a narrow line in pixels. We can do this by
+ // getting the width of the start pattern and dividing by 4 because its
+ // made up of 4 narrow lines.
+ narrowLineWidth = (startPattern[1] - startPattern[0]) >> 2;
+ validateQuietZone(row, startPattern[0]);
+ return startPattern;
+ } catch (ReaderException re) {
+ delete [] startPattern;
+ throw re;
+ }
+ }
+
+ /**
+ * 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* ITFReader::decodeEnd(Ref<BitArray> row) {
+ // For convenience, reverse the row and then
+ // search from 'the start' for the end block
+ row->reverse();
+ int* endPattern = 0;
+ try {
+ int endStart = skipWhiteSpace(row);
+ endPattern = findGuardPattern(row, endStart, END_PATTERN_REVERSED, END_PATTERN_REVERSED_LEN);
+
+ // 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 recalculate the indices of where the 'endblock' starts & stops to
+ // accommodate
+ // the reversed nature of the search
+ int temp = endPattern[0];
+ endPattern[0] = row->getSize() - endPattern[1];
+ endPattern[1] = row->getSize() - temp;
+
+ row->reverse();
+ return endPattern;
+ } catch (ReaderException re) {
+ delete [] endPattern;
+ row->reverse();
+ throw re;
+ }
+ }
+
+ /**
+ * 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. Scan back until
+ * we either get to the start of the barcode or match the necessary number of
+ * quiet zone pixels.
+ *
+ * Note: Its assumed the row is reversed when using this method to find
+ * quiet zone after the end pattern.
+ *
+ * ref: http://www.barcode-1.net/i25code.html
+ *
+ * @param row bit array representing the scanned barcode.
+ * @param startPattern index into row of the start or end pattern.
+ * @throws ReaderException if the quiet zone cannot be found, a ReaderException is thrown.
+ */
+ void ITFReader::validateQuietZone(Ref<BitArray> row, int startPattern) {
+//#pragma mark needs some corrections
+// int quietCount = narrowLineWidth * 10; // expect to find this many pixels of quiet zone
+//
+// for (int i = startPattern - 1; quietCount > 0 && i >= 0; i--) {
+// if (row->get(i)) {
+// break;
+// }
+// quietCount--;
+// }
+// if (quietCount != 0) {
+// // Unable to find the necessary number of quiet zone pixels.
+// throw ReaderException("Unable to find the necessary number of quiet zone pixels");
+// }
+ }
+
+ /**
+ * 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
+ */
+ int ITFReader::skipWhiteSpace(Ref<BitArray> row) {
+ int width = row->getSize();
+ int endStart = 0;
+ while (endStart < width) {
+ if (row->get(endStart)) {
+ break;
+ }
+ endStart++;
+ }
+ if (endStart == width) {
+ throw 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* ITFReader::findGuardPattern(Ref<BitArray> row, int rowOffset, const int pattern[],
+ int patternLen) {
+ // TODO: This is very similar to implementation in UPCEANReader. Consider if they can be
+ // merged to a single method.
+ int patternLength = patternLen;
+ int counters[patternLength];
+ for (int i=0; i<patternLength; i++) {
+ counters[i] = 0;
+ }
+ 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) {
+ counters[counterPosition]++;
+ } else {
+ if (counterPosition == patternLength - 1) {
+ if (patternMatchVariance(counters, patternLength, pattern,
+ MAX_INDIVIDUAL_VARIANCE) < MAX_AVG_VARIANCE) {
+ int* resultValue = new int[2];
+ resultValue[0] = patternStart;
+ resultValue[1] = x;
+ return resultValue;
+ }
+ 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("");
+ }
+
+ /**
+ * Attempts to decode a sequence of ITF black/white lines into single
+ * digit.
+ *
+ * @param counters the counts of runs of observed black/white/black/... values
+ * @return The decoded digit
+ * @throws ReaderException if digit cannot be decoded
+ */
+ int ITFReader::decodeDigit(int counters[], int countersLen){
+ unsigned int bestVariance = MAX_AVG_VARIANCE; // worst variance we'll accept
+ int bestMatch = -1;
+ int max = PATTERNS_LEN;
+ for (int i = 0; i < max; i++) {
+ int pattern[countersLen];
+ for(int ind = 0; ind<countersLen; ind++){
+ pattern[ind] = PATTERNS[i][ind];
+ }
+ unsigned int variance = patternMatchVariance(counters, countersLen, pattern,
+ MAX_INDIVIDUAL_VARIANCE);
+ if (variance < bestVariance) {
+ bestVariance = variance;
+ bestMatch = i;
+ }
+ }
+ if (bestMatch >= 0) {
+ return bestMatch;
+ } else {
+ throw ReaderException("digit didint found");
+ }
+ }
+
+ ITFReader::~ITFReader(){
+ }
+ }
}
projects / zxing.git / blobdiff