mirror of
https://github.com/zxing/zxing.git
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tweak formating
git-svn-id: https://zxing.googlecode.com/svn/trunk@2489 59b500cc-1b3d-0410-9834-0bbf25fbcc57
This commit is contained in:
smparkes@smparkes.net
parent
1cb7380961
commit
7a82d685a3
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@ -33,272 +33,276 @@
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namespace math_utils = zxing::common::detector::math_utils;
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namespace zxing {
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namespace qrcode {
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using std::ostringstream;
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using std::min;
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using std::max;
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using std::isnan;
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using zxing::qrcode::Detector;
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using zxing::Ref;
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using zxing::BitMatrix;
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using zxing::ResultPointCallback;
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using zxing::DetectorResult;
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using zxing::PerspectiveTransform;
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using zxing::qrcode::AlignmentPattern;
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using namespace std;
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Detector::Detector(Ref<BitMatrix> image) :
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image_(image) {
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}
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Detector::Detector(Ref<BitMatrix> image) :
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image_(image) {
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}
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Ref<BitMatrix> Detector::getImage() const {
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return image_;
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}
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Ref<BitMatrix> Detector::getImage() const {
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return image_;
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}
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Ref<ResultPointCallback> Detector::getResultPointCallback() const {
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return callback_;
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}
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Ref<ResultPointCallback> Detector::getResultPointCallback() const {
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return callback_;
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}
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Ref<DetectorResult> Detector::detect(DecodeHints const& hints) {
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callback_ = hints.getResultPointCallback();
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FinderPatternFinder finder(image_, hints.getResultPointCallback());
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Ref<FinderPatternInfo> info(finder.find(hints));
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return processFinderPatternInfo(info);
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}
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Ref<DetectorResult> Detector::detect(DecodeHints const& hints) {
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callback_ = hints.getResultPointCallback();
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FinderPatternFinder finder(image_, hints.getResultPointCallback());
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Ref<FinderPatternInfo> info(finder.find(hints));
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return processFinderPatternInfo(info);
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}
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Ref<DetectorResult> Detector::processFinderPatternInfo(Ref<FinderPatternInfo> info){
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Ref<FinderPattern> topLeft(info->getTopLeft());
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Ref<FinderPattern> topRight(info->getTopRight());
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Ref<FinderPattern> bottomLeft(info->getBottomLeft());
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Ref<DetectorResult> Detector::processFinderPatternInfo(Ref<FinderPatternInfo> info){
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Ref<FinderPattern> topLeft(info->getTopLeft());
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Ref<FinderPattern> topRight(info->getTopRight());
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Ref<FinderPattern> bottomLeft(info->getBottomLeft());
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float moduleSize = calculateModuleSize(topLeft, topRight, bottomLeft);
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if (moduleSize < 1.0f) {
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throw zxing::ReaderException("bad module size");
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}
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int dimension = computeDimension(topLeft, topRight, bottomLeft, moduleSize);
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Version *provisionalVersion = Version::getProvisionalVersionForDimension(dimension);
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int modulesBetweenFPCenters = provisionalVersion->getDimensionForVersion() - 7;
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float moduleSize = calculateModuleSize(topLeft, topRight, bottomLeft);
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if (moduleSize < 1.0f) {
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throw zxing::ReaderException("bad module size");
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}
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int dimension = computeDimension(topLeft, topRight, bottomLeft, moduleSize);
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Version *provisionalVersion = Version::getProvisionalVersionForDimension(dimension);
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int modulesBetweenFPCenters = provisionalVersion->getDimensionForVersion() - 7;
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Ref<AlignmentPattern> alignmentPattern;
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// Anything above version 1 has an alignment pattern
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if (provisionalVersion->getAlignmentPatternCenters().size() > 0) {
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Ref<AlignmentPattern> alignmentPattern;
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// Anything above version 1 has an alignment pattern
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if (provisionalVersion->getAlignmentPatternCenters().size() > 0) {
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// Guess where a "bottom right" finder pattern would have been
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float bottomRightX = topRight->getX() - topLeft->getX() + bottomLeft->getX();
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float bottomRightY = topRight->getY() - topLeft->getY() + bottomLeft->getY();
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// Guess where a "bottom right" finder pattern would have been
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float bottomRightX = topRight->getX() - topLeft->getX() + bottomLeft->getX();
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float bottomRightY = topRight->getY() - topLeft->getY() + bottomLeft->getY();
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// Estimate that alignment pattern is closer by 3 modules
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// from "bottom right" to known top left location
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float correctionToTopLeft = 1.0f - 3.0f / (float)modulesBetweenFPCenters;
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int estAlignmentX = (int)(topLeft->getX() + correctionToTopLeft * (bottomRightX - topLeft->getX()));
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int estAlignmentY = (int)(topLeft->getY() + correctionToTopLeft * (bottomRightY - topLeft->getY()));
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// Estimate that alignment pattern is closer by 3 modules
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// from "bottom right" to known top left location
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float correctionToTopLeft = 1.0f - 3.0f / (float)modulesBetweenFPCenters;
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int estAlignmentX = (int)(topLeft->getX() + correctionToTopLeft * (bottomRightX - topLeft->getX()));
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int estAlignmentY = (int)(topLeft->getY() + correctionToTopLeft * (bottomRightY - topLeft->getY()));
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// Kind of arbitrary -- expand search radius before giving up
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for (int i = 4; i <= 16; i <<= 1) {
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try {
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alignmentPattern = findAlignmentInRegion(moduleSize, estAlignmentX, estAlignmentY, (float)i);
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break;
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} catch (zxing::ReaderException const& re) {
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// try next round
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}
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}
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if (alignmentPattern == 0) {
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// Try anyway
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}
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}
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Ref<PerspectiveTransform> transform = createTransform(topLeft, topRight, bottomLeft, alignmentPattern, dimension);
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Ref<BitMatrix> bits(sampleGrid(image_, dimension, transform));
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std::vector<Ref<ResultPoint> > points(alignmentPattern == 0 ? 3 : 4);
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points[0].reset(bottomLeft);
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points[1].reset(topLeft);
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points[2].reset(topRight);
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if (alignmentPattern != 0) {
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points[3].reset(alignmentPattern);
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}
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Ref<DetectorResult> result(new DetectorResult(bits, points));
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return result;
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}
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Ref<PerspectiveTransform> Detector::createTransform(Ref<ResultPoint> topLeft, Ref<ResultPoint> topRight, Ref <
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ResultPoint > bottomLeft, Ref<ResultPoint> alignmentPattern, int dimension) {
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float dimMinusThree = (float)dimension - 3.5f;
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float bottomRightX;
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float bottomRightY;
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float sourceBottomRightX;
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float sourceBottomRightY;
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if (alignmentPattern != 0) {
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bottomRightX = alignmentPattern->getX();
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bottomRightY = alignmentPattern->getY();
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sourceBottomRightX = dimMinusThree - 3.0f;
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sourceBottomRightY = sourceBottomRightX;
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} else {
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// Don't have an alignment pattern, just make up the bottom-right point
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bottomRightX = (topRight->getX() - topLeft->getX()) + bottomLeft->getX();
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bottomRightY = (topRight->getY() - topLeft->getY()) + bottomLeft->getY();
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sourceBottomRightX = dimMinusThree;
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sourceBottomRightY = dimMinusThree;
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}
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Ref<PerspectiveTransform> transform(PerspectiveTransform::quadrilateralToQuadrilateral(3.5f, 3.5f, dimMinusThree, 3.5f, sourceBottomRightX,
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sourceBottomRightY, 3.5f, dimMinusThree, topLeft->getX(), topLeft->getY(), topRight->getX(),
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topRight->getY(), bottomRightX, bottomRightY, bottomLeft->getX(), bottomLeft->getY()));
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return transform;
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}
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Ref<BitMatrix> Detector::sampleGrid(Ref<BitMatrix> image, int dimension, Ref<PerspectiveTransform> transform) {
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GridSampler &sampler = GridSampler::getInstance();
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return sampler.sampleGrid(image, dimension, transform);
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}
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int Detector::computeDimension(Ref<ResultPoint> topLeft, Ref<ResultPoint> topRight, Ref<ResultPoint> bottomLeft,
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float moduleSize) {
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int tltrCentersDimension =
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math_utils::round(ResultPoint::distance(topLeft, topRight) / moduleSize);
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int tlblCentersDimension =
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math_utils::round(ResultPoint::distance(topLeft, bottomLeft) / moduleSize);
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int dimension = ((tltrCentersDimension + tlblCentersDimension) >> 1) + 7;
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switch (dimension & 0x03) { // mod 4
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case 0:
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dimension++;
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// Kind of arbitrary -- expand search radius before giving up
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for (int i = 4; i <= 16; i <<= 1) {
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try {
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alignmentPattern = findAlignmentInRegion(moduleSize, estAlignmentX, estAlignmentY, (float)i);
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break;
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// 1? do nothing
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case 2:
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dimension--;
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break;
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case 3:
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ostringstream s;
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s << "Bad dimension: " << dimension;
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throw zxing::ReaderException(s.str().c_str());
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} catch (zxing::ReaderException const& re) {
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// try next round
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}
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return dimension;
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}
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float Detector::calculateModuleSize(Ref<ResultPoint> topLeft, Ref<ResultPoint> topRight, Ref<ResultPoint> bottomLeft) {
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// Take the average
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return (calculateModuleSizeOneWay(topLeft, topRight) + calculateModuleSizeOneWay(topLeft, bottomLeft)) / 2.0f;
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}
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float Detector::calculateModuleSizeOneWay(Ref<ResultPoint> pattern, Ref<ResultPoint> otherPattern) {
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float moduleSizeEst1 = sizeOfBlackWhiteBlackRunBothWays((int)pattern->getX(), (int)pattern->getY(),
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(int)otherPattern->getX(), (int)otherPattern->getY());
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float moduleSizeEst2 = sizeOfBlackWhiteBlackRunBothWays((int)otherPattern->getX(), (int)otherPattern->getY(),
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(int)pattern->getX(), (int)pattern->getY());
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if (isnan(moduleSizeEst1)) {
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return moduleSizeEst2;
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}
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if (isnan(moduleSizeEst2)) {
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return moduleSizeEst1;
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}
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// Average them, and divide by 7 since we've counted the width of 3 black modules,
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// and 1 white and 1 black module on either side. Ergo, divide sum by 14.
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return (moduleSizeEst1 + moduleSizeEst2) / 14.0f;
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}
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float Detector::sizeOfBlackWhiteBlackRunBothWays(int fromX, int fromY, int toX, int toY) {
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float result = sizeOfBlackWhiteBlackRun(fromX, fromY, toX, toY);
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// Now count other way -- don't run off image though of course
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float scale = 1.0f;
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int otherToX = fromX - (toX - fromX);
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if (otherToX < 0) {
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scale = (float) fromX / (float) (fromX - otherToX);
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otherToX = 0;
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} else if (otherToX >= (int)image_->getWidth()) {
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scale = (float) (image_->getWidth() - 1 - fromX) / (float) (otherToX - fromX);
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otherToX = image_->getWidth() - 1;
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}
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int otherToY = (int) (fromY - (toY - fromY) * scale);
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scale = 1.0f;
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if (otherToY < 0) {
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scale = (float) fromY / (float) (fromY - otherToY);
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otherToY = 0;
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} else if (otherToY >= (int)image_->getHeight()) {
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scale = (float) (image_->getHeight() - 1 - fromY) / (float) (otherToY - fromY);
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otherToY = image_->getHeight() - 1;
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}
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otherToX = (int) (fromX + (otherToX - fromX) * scale);
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result += sizeOfBlackWhiteBlackRun(fromX, fromY, otherToX, otherToY);
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// Middle pixel is double-counted this way; subtract 1
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return result - 1.0f;
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}
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float Detector::sizeOfBlackWhiteBlackRun(int fromX, int fromY, int toX, int toY) {
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// Mild variant of Bresenham's algorithm;
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// see http://en.wikipedia.org/wiki/Bresenham's_line_algorithm
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bool steep = abs(toY - fromY) > abs(toX - fromX);
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if (steep) {
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int temp = fromX;
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fromX = fromY;
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fromY = temp;
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temp = toX;
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toX = toY;
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toY = temp;
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}
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int dx = abs(toX - fromX);
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int dy = abs(toY - fromY);
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int error = -dx >> 1;
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int xstep = fromX < toX ? 1 : -1;
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int ystep = fromY < toY ? 1 : -1;
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// In black pixels, looking for white, first or second time.
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int state = 0;
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// Loop up until x == toX, but not beyond
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int xLimit = toX + xstep;
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for (int x = fromX, y = fromY; x != xLimit; x += xstep) {
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int realX = steep ? y : x;
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int realY = steep ? x : y;
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// Does current pixel mean we have moved white to black or vice versa?
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if (!((state == 1) ^ image_->get(realX, realY))) {
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if (state == 2) {
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return math_utils::distance(x, y, fromX, fromY);
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}
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state++;
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}
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error += dy;
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if (error > 0) {
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if (y == toY) {
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break;
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}
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y += ystep;
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error -= dx;
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}
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}
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// Found black-white-black; give the benefit of the doubt that the next pixel outside the image
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// is "white" so this last point at (toX+xStep,toY) is the right ending. This is really a
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// small approximation; (toX+xStep,toY+yStep) might be really correct. Ignore this.
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if (state == 2) {
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return math_utils::distance(toX + xstep, toY, fromX, fromY);
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}
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// else we didn't find even black-white-black; no estimate is really possible
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return NAN;
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}
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Ref<AlignmentPattern> Detector::findAlignmentInRegion(float overallEstModuleSize, int estAlignmentX, int estAlignmentY,
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float allowanceFactor) {
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// Look for an alignment pattern (3 modules in size) around where it
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// should be
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int allowance = (int)(allowanceFactor * overallEstModuleSize);
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int alignmentAreaLeftX = max(0, estAlignmentX - allowance);
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int alignmentAreaRightX = min((int)(image_->getWidth() - 1), estAlignmentX + allowance);
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if (alignmentAreaRightX - alignmentAreaLeftX < overallEstModuleSize * 3) {
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throw zxing::ReaderException("region too small to hold alignment pattern");
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}
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int alignmentAreaTopY = max(0, estAlignmentY - allowance);
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int alignmentAreaBottomY = min((int)(image_->getHeight() - 1), estAlignmentY + allowance);
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if (alignmentAreaBottomY - alignmentAreaTopY < overallEstModuleSize * 3) {
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throw zxing::ReaderException("region too small to hold alignment pattern");
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}
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AlignmentPatternFinder alignmentFinder(image_, alignmentAreaLeftX, alignmentAreaTopY, alignmentAreaRightX
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- alignmentAreaLeftX, alignmentAreaBottomY - alignmentAreaTopY, overallEstModuleSize, callback_);
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return alignmentFinder.find();
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if (alignmentPattern == 0) {
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// Try anyway
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}
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}
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Ref<PerspectiveTransform> transform = createTransform(topLeft, topRight, bottomLeft, alignmentPattern, dimension);
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Ref<BitMatrix> bits(sampleGrid(image_, dimension, transform));
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std::vector<Ref<ResultPoint> > points(alignmentPattern == 0 ? 3 : 4);
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points[0].reset(bottomLeft);
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points[1].reset(topLeft);
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points[2].reset(topRight);
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if (alignmentPattern != 0) {
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points[3].reset(alignmentPattern);
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}
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Ref<DetectorResult> result(new DetectorResult(bits, points));
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return result;
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}
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Ref<PerspectiveTransform> Detector::createTransform(Ref<ResultPoint> topLeft, Ref<ResultPoint> topRight, Ref <
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ResultPoint > bottomLeft, Ref<ResultPoint> alignmentPattern, int dimension) {
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float dimMinusThree = (float)dimension - 3.5f;
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float bottomRightX;
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float bottomRightY;
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float sourceBottomRightX;
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float sourceBottomRightY;
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if (alignmentPattern != 0) {
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bottomRightX = alignmentPattern->getX();
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bottomRightY = alignmentPattern->getY();
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sourceBottomRightX = dimMinusThree - 3.0f;
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sourceBottomRightY = sourceBottomRightX;
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} else {
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// Don't have an alignment pattern, just make up the bottom-right point
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bottomRightX = (topRight->getX() - topLeft->getX()) + bottomLeft->getX();
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bottomRightY = (topRight->getY() - topLeft->getY()) + bottomLeft->getY();
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sourceBottomRightX = dimMinusThree;
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sourceBottomRightY = dimMinusThree;
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}
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Ref<PerspectiveTransform> transform(PerspectiveTransform::quadrilateralToQuadrilateral(3.5f, 3.5f, dimMinusThree, 3.5f, sourceBottomRightX,
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sourceBottomRightY, 3.5f, dimMinusThree, topLeft->getX(), topLeft->getY(), topRight->getX(),
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topRight->getY(), bottomRightX, bottomRightY, bottomLeft->getX(), bottomLeft->getY()));
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return transform;
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}
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Ref<BitMatrix> Detector::sampleGrid(Ref<BitMatrix> image, int dimension, Ref<PerspectiveTransform> transform) {
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GridSampler &sampler = GridSampler::getInstance();
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return sampler.sampleGrid(image, dimension, transform);
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}
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int Detector::computeDimension(Ref<ResultPoint> topLeft, Ref<ResultPoint> topRight, Ref<ResultPoint> bottomLeft,
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float moduleSize) {
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int tltrCentersDimension =
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math_utils::round(ResultPoint::distance(topLeft, topRight) / moduleSize);
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int tlblCentersDimension =
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math_utils::round(ResultPoint::distance(topLeft, bottomLeft) / moduleSize);
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int dimension = ((tltrCentersDimension + tlblCentersDimension) >> 1) + 7;
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switch (dimension & 0x03) { // mod 4
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case 0:
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dimension++;
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break;
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// 1? do nothing
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case 2:
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dimension--;
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break;
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case 3:
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ostringstream s;
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s << "Bad dimension: " << dimension;
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throw zxing::ReaderException(s.str().c_str());
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}
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return dimension;
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}
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float Detector::calculateModuleSize(Ref<ResultPoint> topLeft, Ref<ResultPoint> topRight, Ref<ResultPoint> bottomLeft) {
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// Take the average
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return (calculateModuleSizeOneWay(topLeft, topRight) + calculateModuleSizeOneWay(topLeft, bottomLeft)) / 2.0f;
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}
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float Detector::calculateModuleSizeOneWay(Ref<ResultPoint> pattern, Ref<ResultPoint> otherPattern) {
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float moduleSizeEst1 = sizeOfBlackWhiteBlackRunBothWays((int)pattern->getX(), (int)pattern->getY(),
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(int)otherPattern->getX(), (int)otherPattern->getY());
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float moduleSizeEst2 = sizeOfBlackWhiteBlackRunBothWays((int)otherPattern->getX(), (int)otherPattern->getY(),
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(int)pattern->getX(), (int)pattern->getY());
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if (isnan(moduleSizeEst1)) {
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return moduleSizeEst2;
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}
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if (isnan(moduleSizeEst2)) {
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return moduleSizeEst1;
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}
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// Average them, and divide by 7 since we've counted the width of 3 black modules,
|
||||
// and 1 white and 1 black module on either side. Ergo, divide sum by 14.
|
||||
return (moduleSizeEst1 + moduleSizeEst2) / 14.0f;
|
||||
}
|
||||
|
||||
float Detector::sizeOfBlackWhiteBlackRunBothWays(int fromX, int fromY, int toX, int toY) {
|
||||
|
||||
float result = sizeOfBlackWhiteBlackRun(fromX, fromY, toX, toY);
|
||||
|
||||
// Now count other way -- don't run off image though of course
|
||||
float scale = 1.0f;
|
||||
int otherToX = fromX - (toX - fromX);
|
||||
if (otherToX < 0) {
|
||||
scale = (float) fromX / (float) (fromX - otherToX);
|
||||
otherToX = 0;
|
||||
} else if (otherToX >= (int)image_->getWidth()) {
|
||||
scale = (float) (image_->getWidth() - 1 - fromX) / (float) (otherToX - fromX);
|
||||
otherToX = image_->getWidth() - 1;
|
||||
}
|
||||
int otherToY = (int) (fromY - (toY - fromY) * scale);
|
||||
|
||||
scale = 1.0f;
|
||||
if (otherToY < 0) {
|
||||
scale = (float) fromY / (float) (fromY - otherToY);
|
||||
otherToY = 0;
|
||||
} else if (otherToY >= (int)image_->getHeight()) {
|
||||
scale = (float) (image_->getHeight() - 1 - fromY) / (float) (otherToY - fromY);
|
||||
otherToY = image_->getHeight() - 1;
|
||||
}
|
||||
otherToX = (int) (fromX + (otherToX - fromX) * scale);
|
||||
|
||||
result += sizeOfBlackWhiteBlackRun(fromX, fromY, otherToX, otherToY);
|
||||
|
||||
// Middle pixel is double-counted this way; subtract 1
|
||||
return result - 1.0f;
|
||||
}
|
||||
|
||||
float Detector::sizeOfBlackWhiteBlackRun(int fromX, int fromY, int toX, int toY) {
|
||||
// Mild variant of Bresenham's algorithm;
|
||||
// see http://en.wikipedia.org/wiki/Bresenham's_line_algorithm
|
||||
bool steep = abs(toY - fromY) > abs(toX - fromX);
|
||||
if (steep) {
|
||||
int temp = fromX;
|
||||
fromX = fromY;
|
||||
fromY = temp;
|
||||
temp = toX;
|
||||
toX = toY;
|
||||
toY = temp;
|
||||
}
|
||||
|
||||
int dx = abs(toX - fromX);
|
||||
int dy = abs(toY - fromY);
|
||||
int error = -dx >> 1;
|
||||
int xstep = fromX < toX ? 1 : -1;
|
||||
int ystep = fromY < toY ? 1 : -1;
|
||||
|
||||
// In black pixels, looking for white, first or second time.
|
||||
int state = 0;
|
||||
// Loop up until x == toX, but not beyond
|
||||
int xLimit = toX + xstep;
|
||||
for (int x = fromX, y = fromY; x != xLimit; x += xstep) {
|
||||
int realX = steep ? y : x;
|
||||
int realY = steep ? x : y;
|
||||
|
||||
// Does current pixel mean we have moved white to black or vice versa?
|
||||
if (!((state == 1) ^ image_->get(realX, realY))) {
|
||||
if (state == 2) {
|
||||
return math_utils::distance(x, y, fromX, fromY);
|
||||
}
|
||||
state++;
|
||||
}
|
||||
|
||||
error += dy;
|
||||
if (error > 0) {
|
||||
if (y == toY) {
|
||||
break;
|
||||
}
|
||||
y += ystep;
|
||||
error -= dx;
|
||||
}
|
||||
}
|
||||
// Found black-white-black; give the benefit of the doubt that the next pixel outside the image
|
||||
// is "white" so this last point at (toX+xStep,toY) is the right ending. This is really a
|
||||
// small approximation; (toX+xStep,toY+yStep) might be really correct. Ignore this.
|
||||
if (state == 2) {
|
||||
return math_utils::distance(toX + xstep, toY, fromX, fromY);
|
||||
}
|
||||
// else we didn't find even black-white-black; no estimate is really possible
|
||||
return NAN;
|
||||
}
|
||||
|
||||
Ref<AlignmentPattern> Detector::findAlignmentInRegion(float overallEstModuleSize, int estAlignmentX, int estAlignmentY,
|
||||
float allowanceFactor) {
|
||||
// Look for an alignment pattern (3 modules in size) around where it
|
||||
// should be
|
||||
int allowance = (int)(allowanceFactor * overallEstModuleSize);
|
||||
int alignmentAreaLeftX = max(0, estAlignmentX - allowance);
|
||||
int alignmentAreaRightX = min((int)(image_->getWidth() - 1), estAlignmentX + allowance);
|
||||
if (alignmentAreaRightX - alignmentAreaLeftX < overallEstModuleSize * 3) {
|
||||
throw zxing::ReaderException("region too small to hold alignment pattern");
|
||||
}
|
||||
int alignmentAreaTopY = max(0, estAlignmentY - allowance);
|
||||
int alignmentAreaBottomY = min((int)(image_->getHeight() - 1), estAlignmentY + allowance);
|
||||
if (alignmentAreaBottomY - alignmentAreaTopY < overallEstModuleSize * 3) {
|
||||
throw zxing::ReaderException("region too small to hold alignment pattern");
|
||||
}
|
||||
|
||||
AlignmentPatternFinder alignmentFinder(image_, alignmentAreaLeftX, alignmentAreaTopY, alignmentAreaRightX
|
||||
- alignmentAreaLeftX, alignmentAreaBottomY - alignmentAreaTopY, overallEstModuleSize, callback_);
|
||||
return alignmentFinder.find();
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in a new issue