hints)
{
//resultPointCallback = hints == null ? null : (ResultPointCallback)hints[DecodeHintType.NEED_RESULT_POINT_CALLBACK];
ResultPointCallback resultPointCallback = null;
if (hints != null && hints.ContainsKey(DecodeHintType.NEED_RESULT_POINT_CALLBACK))
{
resultPointCallback = (ResultPointCallback)hints[DecodeHintType.NEED_RESULT_POINT_CALLBACK];
}
FinderPatternFinder finder = new FinderPatternFinder(image, resultPointCallback);
FinderPatternInfo info = finder.find(hints);
return processFinderPatternInfo(info);
}
//JAVA TO C# CONVERTER WARNING: Method 'throws' clauses are not available in .NET:
//ORIGINAL LINE: protected final com.google.zxing.common.DetectorResult processFinderPatternInfo(FinderPatternInfo info) throws com.google.zxing.NotFoundException, com.google.zxing.FormatException
protected internal DetectorResult processFinderPatternInfo(FinderPatternInfo info)
{
FinderPattern topLeft = info.TopLeft;
FinderPattern topRight = info.TopRight;
FinderPattern bottomLeft = info.BottomLeft;
float moduleSize = calculateModuleSize(topLeft, topRight, bottomLeft);
if (moduleSize < 1.0f)
{
throw NotFoundException.NotFoundInstance;
}
int dimension = computeDimension(topLeft, topRight, bottomLeft, moduleSize);
Version provisionalVersion = Version.getProvisionalVersionForDimension(dimension);
int modulesBetweenFPCenters = provisionalVersion.DimensionForVersion - 7;
AlignmentPattern alignmentPattern = null;
// Anything above version 1 has an alignment pattern
if (provisionalVersion.AlignmentPatternCenters.Length > 0)
{
// Guess where a "bottom right" finder pattern would have been
float bottomRightX = topRight.X - topLeft.X + bottomLeft.X;
float bottomRightY = topRight.Y - topLeft.Y + bottomLeft.Y;
// Estimate that alignment pattern is closer by 3 modules
// from "bottom right" to known top left location
float correctionToTopLeft = 1.0f - 3.0f / (float) modulesBetweenFPCenters;
int estAlignmentX = (int)(topLeft.X + correctionToTopLeft * (bottomRightX - topLeft.X));
int estAlignmentY = (int)(topLeft.Y + correctionToTopLeft * (bottomRightY - topLeft.Y));
// Kind of arbitrary -- expand search radius before giving up
for (int i = 4; i <= 16; i <<= 1)
{
try
{
alignmentPattern = findAlignmentInRegion(moduleSize, estAlignmentX, estAlignmentY, (float) i);
break;
}
catch (NotFoundException re)
{
// try next round
}
}
// If we didn't find alignment pattern... well try anyway without it
}
PerspectiveTransform transform = createTransform(topLeft, topRight, bottomLeft, alignmentPattern, dimension);
BitMatrix bits = sampleGrid(image, transform, dimension);
ResultPoint[] points;
if (alignmentPattern == null)
{
points = new ResultPoint[]{bottomLeft, topLeft, topRight};
}
else
{
points = new ResultPoint[]{bottomLeft, topLeft, topRight, alignmentPattern};
}
return new DetectorResult(bits, points);
}
private static PerspectiveTransform createTransform(ResultPoint topLeft, ResultPoint topRight, ResultPoint bottomLeft, ResultPoint alignmentPattern, int dimension)
{
float dimMinusThree = (float) dimension - 3.5f;
float bottomRightX;
float bottomRightY;
float sourceBottomRightX;
float sourceBottomRightY;
if (alignmentPattern != null)
{
bottomRightX = alignmentPattern.X;
bottomRightY = alignmentPattern.Y;
sourceBottomRightX = dimMinusThree - 3.0f;
sourceBottomRightY = sourceBottomRightX;
}
else
{
// Don't have an alignment pattern, just make up the bottom-right point
bottomRightX = (topRight.X - topLeft.X) + bottomLeft.X;
bottomRightY = (topRight.Y - topLeft.Y) + bottomLeft.Y;
sourceBottomRightX = dimMinusThree;
sourceBottomRightY = dimMinusThree;
}
return PerspectiveTransform.quadrilateralToQuadrilateral(3.5f, 3.5f, dimMinusThree, 3.5f, sourceBottomRightX, sourceBottomRightY, 3.5f, dimMinusThree, topLeft.X, topLeft.Y, topRight.X, topRight.Y, bottomRightX, bottomRightY, bottomLeft.X, bottomLeft.Y);
}
//JAVA TO C# CONVERTER WARNING: Method 'throws' clauses are not available in .NET:
//ORIGINAL LINE: private static com.google.zxing.common.BitMatrix sampleGrid(com.google.zxing.common.BitMatrix image, com.google.zxing.common.PerspectiveTransform transform, int dimension) throws com.google.zxing.NotFoundException
private static BitMatrix sampleGrid(BitMatrix image, PerspectiveTransform transform, int dimension)
{
GridSampler sampler = GridSampler.Instance;
return sampler.sampleGrid(image, dimension, dimension, transform);
}
///
/// Computes the dimension (number of modules on a size) of the QR Code based on the position
/// of the finder patterns and estimated module size.
///
//JAVA TO C# CONVERTER WARNING: Method 'throws' clauses are not available in .NET:
//ORIGINAL LINE: private static int computeDimension(com.google.zxing.ResultPoint topLeft, com.google.zxing.ResultPoint topRight, com.google.zxing.ResultPoint bottomLeft, float moduleSize) throws com.google.zxing.NotFoundException
private static int computeDimension(ResultPoint topLeft, ResultPoint topRight, ResultPoint bottomLeft, float moduleSize)
{
int tltrCentersDimension = MathUtils.round(ResultPoint.distance(topLeft, topRight) / moduleSize);
int tlblCentersDimension = MathUtils.round(ResultPoint.distance(topLeft, bottomLeft) / moduleSize);
int dimension = ((tltrCentersDimension + tlblCentersDimension) >> 1) + 7;
switch (dimension & 0x03) // mod 4
{
case 0:
dimension++;
break;
// 1? do nothing
case 2:
dimension--;
break;
case 3:
throw NotFoundException.NotFoundInstance;
}
return dimension;
}
///
/// Computes an average estimated module size based on estimated derived from the positions
/// of the three finder patterns.
///
protected internal float calculateModuleSize(ResultPoint topLeft, ResultPoint topRight, ResultPoint bottomLeft)
{
// Take the average
return (calculateModuleSizeOneWay(topLeft, topRight) + calculateModuleSizeOneWay(topLeft, bottomLeft)) / 2.0f;
}
///
/// Estimates module size based on two finder patterns -- it uses
/// to figure the
/// width of each, measuring along the axis between their centers.
///
private float calculateModuleSizeOneWay(ResultPoint pattern, ResultPoint otherPattern)
{
float moduleSizeEst1 = sizeOfBlackWhiteBlackRunBothWays((int) pattern.X, (int) pattern.Y, (int) otherPattern.X, (int) otherPattern.Y);
float moduleSizeEst2 = sizeOfBlackWhiteBlackRunBothWays((int) otherPattern.X, (int) otherPattern.Y, (int) pattern.X, (int) pattern.Y);
if (float.IsNaN(moduleSizeEst1))
{
return moduleSizeEst2 / 7.0f;
}
if (float.IsNaN(moduleSizeEst2))
{
return moduleSizeEst1 / 7.0f;
}
// 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;
}
///
/// See ; computes the total width of
/// a finder pattern by looking for a black-white-black run from the center in the direction
/// of another point (another finder pattern center), and in the opposite direction too.
///
private float 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 >= image.Width)
{
scale = (float)(image.Width - 1 - fromX) / (float)(otherToX - fromX);
otherToX = image.Width - 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 >= image.Height)
{
scale = (float)(image.Height - 1 - fromY) / (float)(otherToY - fromY);
otherToY = image.Height - 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;
}
///
/// This method traces a line from a point in the image, in the direction towards another point.
/// It begins in a black region, and keeps going until it finds white, then black, then white again.
/// It reports the distance from the start to this point.
///
/// This is used when figuring out how wide a finder pattern is, when the finder pattern
/// may be skewed or rotated.
///
private float 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 = Math.Abs(toY - fromY) > Math.Abs(toX - fromX);
if (steep)
{
int temp = fromX;
fromX = fromY;
fromY = temp;
temp = toX;
toX = toY;
toY = temp;
}
int dx = Math.Abs(toX - fromX);
int dy = Math.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?
// Scanning black in state 0,2 and white in state 1, so if we find the wrong
// color, advance to next state or end if we are in state 2 already
if ((state == 1) == image.get(realX, realY))
{
if (state == 2)
{
return MathUtils.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 MathUtils.distance(toX + xstep, toY, fromX, fromY);
}
// else we didn't find even black-white-black; no estimate is really possible
return float.NaN;
}
///
/// Attempts to locate an alignment pattern in a limited region of the image, which is
/// guessed to contain it. This method uses .
///
/// estimated module size so far
/// x coordinate of center of area probably containing alignment pattern
/// y coordinate of above
/// number of pixels in all directions to search from the center
/// if found, or null otherwise
/// if an unexpected error occurs during detection
//JAVA TO C# CONVERTER WARNING: Method 'throws' clauses are not available in .NET:
//ORIGINAL LINE: protected final AlignmentPattern findAlignmentInRegion(float overallEstModuleSize, int estAlignmentX, int estAlignmentY, float allowanceFactor) throws com.google.zxing.NotFoundException
protected internal AlignmentPattern 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 = Math.Max(0, estAlignmentX - allowance);
int alignmentAreaRightX = Math.Min(image.Width - 1, estAlignmentX + allowance);
if (alignmentAreaRightX - alignmentAreaLeftX < overallEstModuleSize * 3)
{
throw NotFoundException.NotFoundInstance;
}
int alignmentAreaTopY = Math.Max(0, estAlignmentY - allowance);
int alignmentAreaBottomY = Math.Min(image.Height - 1, estAlignmentY + allowance);
if (alignmentAreaBottomY - alignmentAreaTopY < overallEstModuleSize * 3)
{
throw NotFoundException.NotFoundInstance;
}
AlignmentPatternFinder alignmentFinder = new AlignmentPatternFinder(image, alignmentAreaLeftX, alignmentAreaTopY, alignmentAreaRightX - alignmentAreaLeftX, alignmentAreaBottomY - alignmentAreaTopY, overallEstModuleSize, resultPointCallback);
return alignmentFinder.find();
}
}
}