org.openpnp.vision.pipeline.stages

Class DetectRectlinearSymmetry

java.lang.Object

org.openpnp.vision.pipeline.CvStage

org.openpnp.vision.pipeline.stages.DetectRectlinearSymmetry

public class DetectRectlinearSymmetry
extends CvStage

Finds the object and angle with maximum rectlinear symmetry.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	DetectRectlinearSymmetry.ScoreRange
static class	DetectRectlinearSymmetry.SymmetryFunction Determines how the cross-section across the height of the detected subject is evaluated. FullSymmetry looks for full inner and outline symmetry.

Nested classes/interfaces inherited from class org.openpnp.vision.pipeline.CvStage

CvStage.CvStageBeanInfo, CvStage.Result

Constructor Summary

Constructors

Constructor and Description
DetectRectlinearSymmetry()

Method Summary

Modifier and Type	Method and Description
protected static void	applyCrossSectionContour(int channels, double s, int symmetryWidth, int size, double[] crossSection) Create the contour of the cross-section signal from both sides, meeting at the symmetry point s.
protected static void	applyMasked(int channels, int size, double minFeatureSize, int subSampling, int superSampling, double[] crossSectionMasked, double[] kernel, double[] crossSection) Instead of taking the cross-section cumulative brightness, compare the number of non.zero pixels against the minFeatureSize and apply a step function.
protected static int	findCrossSectionBounds(int channels, double symmetry, int symmetrySize, double[] crossSection) Find the bounds of the symmetry in the cross-section.
protected static java.lang.Double	findCrossSectionSymmetry(int channels, int size, int symmetrySearch, int symmetrySize, DetectRectlinearSymmetry.SymmetryFunction symmetryFunction, double[] crossSection, DetectRectlinearSymmetry.ScoreRange scoreRange) Find the best symmetry in the cross-section.
static RotatedRect	findReclinearSymmetry(Mat image, int xCenter, int yCenter, double expectedAngle, double maxWidth, double maxHeight, double searchDistance, double searchAngle, double minSymmetry, DetectRectlinearSymmetry.SymmetryFunction xSymmetryFunction, DetectRectlinearSymmetry.SymmetryFunction ySymmetryFunction, double minFeatureSize, int subSampling, int superSampling, int gaussianSmoothing, double gamma, int threshold, boolean diagnostics, boolean diagnosticMap, DetectRectlinearSymmetry.ScoreRange scoreRange) Find the angle, location and bounds of the subject with largest rectlinear symmetry.
DetectRectlinearSymmetry.SymmetryFunction	getAsymmetricFunction()
double	getExpectedAngle()
double	getGamma()
double	getMaxHeight()
double	getMaxWidth()
double	getMinFeatureSize()
double	getMinSymmetry()
java.lang.String	getPropertyName()
double	getSearchAngle()
double	getSearchDistance()
int	getSmoothing()
int	getSubSampling()
int	getSuperSampling()
DetectRectlinearSymmetry.SymmetryFunction	getSymmetricFunction()
int	getThreshold()
boolean	isDiagnostics()
boolean	isDiagnosticsMap()
boolean	isSymmetricLeftRight()
boolean	isSymmetricUpperLower()
CvStage.Result	process(CvPipeline pipeline) Perform an operation in a pipeline.
void	setAsymmetricFunction(DetectRectlinearSymmetry.SymmetryFunction symmetryAcrossHeight)
void	setDiagnostics(boolean diagnostics)
void	setDiagnosticsMap(boolean diagnosticsMap)
void	setExpectedAngle(double expectedAngle)
void	setGamma(double gamma)
void	setMaxHeight(double maxHeight)
void	setMaxWidth(double maxWidth)
void	setMinFeatureSize(double minFeatureSize)
void	setMinSymmetry(double minSymmetry)
void	setPropertyName(java.lang.String propertyName)
void	setSearchAngle(double searchAngle)
void	setSearchDistance(double searchDistance)
void	setSmoothing(int smoothing)
void	setSubSampling(int subSampling)
void	setSuperSampling(int superSampling)
void	setSymmetricFunction(DetectRectlinearSymmetry.SymmetryFunction symmetryAcrossWidth)
void	setSymmetricLeftRight(boolean symmetricLeftRight)
void	setSymmetricUpperLower(boolean symmetricUpperLower)
void	setThreshold(int threshold)
protected static double	sumContrast(int channels, int size, double[] crossSection, double[] crossSectionN) Sum the contrast across the cross-section (sum of squares).

Methods inherited from class org.openpnp.vision.pipeline.CvStage

customizePropertySheet, getBeanInfo, getCategory, getDescription, getDescription, getLengthUnit, getName, getPossiblePipelinePropertyOverride, getPossiblePipelinePropertyOverride, isEnabled, recordPropertyOverride, setEnabled, setName

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DetectRectlinearSymmetry

public DetectRectlinearSymmetry()

Method Detail

getExpectedAngle

public double getExpectedAngle()

setExpectedAngle

public void setExpectedAngle(double expectedAngle)

getSearchDistance

public double getSearchDistance()

setSearchDistance

public void setSearchDistance(double searchDistance)

getSearchAngle

public double getSearchAngle()

setSearchAngle

public void setSearchAngle(double searchAngle)

getMaxWidth

public double getMaxWidth()

setMaxWidth

public void setMaxWidth(double maxWidth)

getMaxHeight

public double getMaxHeight()

setMaxHeight

public void setMaxHeight(double maxHeight)

getMinFeatureSize

public double getMinFeatureSize()

setMinFeatureSize

public void setMinFeatureSize(double minFeatureSize)

getSymmetricFunction

public DetectRectlinearSymmetry.SymmetryFunction getSymmetricFunction()

setSymmetricFunction

public void setSymmetricFunction(DetectRectlinearSymmetry.SymmetryFunction symmetryAcrossWidth)

getAsymmetricFunction

public DetectRectlinearSymmetry.SymmetryFunction getAsymmetricFunction()

setAsymmetricFunction

public void setAsymmetricFunction(DetectRectlinearSymmetry.SymmetryFunction symmetryAcrossHeight)

isSymmetricLeftRight

public boolean isSymmetricLeftRight()

setSymmetricLeftRight

public void setSymmetricLeftRight(boolean symmetricLeftRight)

isSymmetricUpperLower

public boolean isSymmetricUpperLower()

setSymmetricUpperLower

public void setSymmetricUpperLower(boolean symmetricUpperLower)

getMinSymmetry

public double getMinSymmetry()

setMinSymmetry

public void setMinSymmetry(double minSymmetry)

getSubSampling

public int getSubSampling()

setSubSampling

public void setSubSampling(int subSampling)

getSuperSampling

public int getSuperSampling()

setSuperSampling

public void setSuperSampling(int superSampling)

getSmoothing

public int getSmoothing()

setSmoothing

public void setSmoothing(int smoothing)

getGamma

public double getGamma()

setGamma

public void setGamma(double gamma)

getThreshold

public int getThreshold()

setThreshold

public void setThreshold(int threshold)

getPropertyName

public java.lang.String getPropertyName()

setPropertyName

public void setPropertyName(java.lang.String propertyName)

isDiagnostics

public boolean isDiagnostics()

setDiagnostics

public void setDiagnostics(boolean diagnostics)

isDiagnosticsMap

public boolean isDiagnosticsMap()

setDiagnosticsMap

public void setDiagnosticsMap(boolean diagnosticsMap)

process

public CvStage.Result process(CvPipeline pipeline)
                       throws java.lang.Exception

Description copied from class: CvStage

Perform an operation in a pipeline. Typical implementations will call CvPipeline#getWorkingImage(), perform some type of operation on the image and will return a Result containing a modified image and model data about features found in the image. If the stage only modifies the working image, it is sufficient to just return null, and this will typically be the most common case.

Specified by:

process in class CvStage

Returns:

Null or a Result object containing an optional image and optional model. If the return value is null the pipeline will store a copy of the working image as the result for this stage. Otherwise it will set the working image to the result image and store the result image.

Throws:

java.lang.Exception

findReclinearSymmetry

public static RotatedRect findReclinearSymmetry(Mat image,
                                                int xCenter,
                                                int yCenter,
                                                double expectedAngle,
                                                double maxWidth,
                                                double maxHeight,
                                                double searchDistance,
                                                double searchAngle,
                                                double minSymmetry,
                                                DetectRectlinearSymmetry.SymmetryFunction xSymmetryFunction,
                                                DetectRectlinearSymmetry.SymmetryFunction ySymmetryFunction,
                                                double minFeatureSize,
                                                int subSampling,
                                                int superSampling,
                                                int gaussianSmoothing,
                                                double gamma,
                                                int threshold,
                                                boolean diagnostics,
                                                boolean diagnosticMap,
                                                DetectRectlinearSymmetry.ScoreRange scoreRange)
                                         throws java.lang.Exception

Find the angle, location and bounds of the subject with largest rectlinear symmetry.

Parameters:

image - The image to be searched.

xCenter - Center, around which the search is to be performed.

yCenter -

expectedAngle - Expected angle of the subject.

maxWidth - Maximum width and height of the searched subject. Must include a margin around it, to detect edges.

maxHeight -

searchDistance - Maximum search distance around the center.

searchAngle - Maximum search angle on both sides of the expected angle.

minSymmetry - Minimum symmetry for a successful detection. Values higher than 1.0 mean symmetry is present.

xSymmetryFunction - The symmetry function determines, how the cross-section is interpreted to find symmetry. See DetectRectlinearSymmetry.SymmetryFunction

ySymmetryFunction -

minFeatureSize - Minimum feature size in pixels, if the SymmetryFunction.OutlineSymmetryMasked is used.

subSampling - To speed up things, the image is first sub-sampled, i.e. only every subSampling × subSampling pixel is analyzed. Once a preliminary match is obtained, recursion is used to refine it.

superSampling - In the final recursion, superSampling is applied, i.e. the sampled pixels are binned into a finder cross-section, allowing for sub-pixel precision.

gaussianSmoothing - Cross-sections are subject to pixel grid interferences if the sampling angle is at 45° multiples. Using Gaussian smoothing with a kernel of this size, this is remedied.

gamma - Pixel luminance is raised to the power of gamma. Choosing > 1 gammas allows for boosting bright areas.

threshold - Pixel luminance threshold for the DetectRectlinearSymmetry.SymmetryFunction OutlineSymmetryMasked option.

diagnostics - Overlay diagnostic cross-hairs and bounds on top of the image.

diagnosticMap - Overlay diagnostic maps for angular contrast and cross-section profiles on top of the image.

scoreRange - Returns symmetry score ranges.

Returns:

Throws:

java.lang.Exception

sumContrast

protected static double sumContrast(int channels,
                                    int size,
                                    double[] crossSection,
                                    double[] crossSectionN)

Sum the contrast across the cross-section (sum of squares).

Parameters:

channels -

size -

crossSection -

crossSectionN -

Returns:

applyMasked

protected static void applyMasked(int channels,
                                  int size,
                                  double minFeatureSize,
                                  int subSampling,
                                  int superSampling,
                                  double[] crossSectionMasked,
                                  double[] kernel,
                                  double[] crossSection)

Instead of taking the cross-section cumulative brightness, compare the number of non.zero pixels against the minFeatureSize and apply a step function. The signal is essentially deciding whether something significant is present or not.

Parameters:

channels -

size -

minFeatureSize -

subSampling -

superSampling -

crossSectionMasked -

kernel -

crossSection -

applyCrossSectionContour

protected static void applyCrossSectionContour(int channels,
                                               double s,
                                               int symmetryWidth,
                                               int size,
                                               double[] crossSection)

Create the contour of the cross-section signal from both sides, meeting at the symmetry point s.

Parameters:

channels -

s -

symmetryWidth -

size -

crossSection -

findCrossSectionSymmetry

protected static java.lang.Double findCrossSectionSymmetry(int channels,
                                                           int size,
                                                           int symmetrySearch,
                                                           int symmetrySize,
                                                           DetectRectlinearSymmetry.SymmetryFunction symmetryFunction,
                                                           double[] crossSection,
                                                           DetectRectlinearSymmetry.ScoreRange scoreRange)

Find the best symmetry in the cross-section. Winner is the maximum rate of left/right-sided variance, divided by the sum of squares of the left vs. right differences.

Parameters:

channels -

size -

symmetrySearch -

symmetrySize -

symmetryFunction -

crossSection -

scoreRange -

Returns:

findCrossSectionBounds

protected static int findCrossSectionBounds(int channels,
                                            double symmetry,
                                            int symmetrySize,
                                            double[] crossSection)

Find the bounds of the symmetry in the cross-section. Looks for the largest symmetric jump in the cross-section signal outline.

Parameters:

channels -

symmetry -

symmetrySize -

crossSection -

Returns: