org.openimaj.image.feature.local.detector.pyramid

Class InterpolatingOctaveExtremaFinder

java.lang.Object

org.openimaj.image.feature.local.detector.pyramid.AbstractOctaveInterestPointFinder<OCTAVE,FImage>

org.openimaj.image.feature.local.detector.pyramid.AbstractOctaveExtremaFinder<GaussianOctave<FImage>>

org.openimaj.image.feature.local.detector.pyramid.BasicOctaveExtremaFinder

org.openimaj.image.feature.local.detector.pyramid.InterpolatingOctaveExtremaFinder

All Implemented Interfaces:

OctaveProcessor<GaussianOctave<FImage>,FImage>, OctaveInterestPointFinder<GaussianOctave<FImage>,FImage>

@Reference(type=Inproceedings,author={"Matthew Brown","D Lowe"},title="Invariant Features from Interest Point Groups",year="2002",booktitle="BMVC 2002: 13th British Machine Vision Conference",pages={"253","","262"},month="September") @Reference(type=Article,author="David Lowe",title="Distinctive image features from scale-invariant keypoints",year="2004",journal="IJCV",pages={"91","110"},month="January",number="2",volume="60")
public class InterpolatingOctaveExtremaFinder
extends BasicOctaveExtremaFinder

Implementation of the method described in "Invariant Features from Interest Point Groups" by Matthew Brown and David Lowe (http://www.cs.ubc.ca/~lowe/papers/brown02.pdf) for improving the localisation of interest points detected in a difference-of-Gaussian by fitting a 3D quadratic to the scale-space Laplacian (approximated by the difference-of-Gaussian pyramid).

Author:

Jonathon Hare (jsh2@ecs.soton.ac.uk)

Field Summary

Fields

Modifier and Type	Field and Description
static int	DEFAULT_INTERPOLATION_ITERATIONS Default number of interpolation iterations
protected int	numInterpolationIterations

Fields inherited from class org.openimaj.image.feature.local.detector.pyramid.BasicOctaveExtremaFinder

DEFAULT_MAGNITUDE_THRESHOLD, magnitudeThreshold, normMagnitudeScales, scales

Fields inherited from class org.openimaj.image.feature.local.detector.pyramid.AbstractOctaveExtremaFinder

DEFAULT_EIGENVALUE_RATIO, eigenvalueRatio

Fields inherited from class org.openimaj.image.feature.local.detector.pyramid.AbstractOctaveInterestPointFinder

currentScaleIndex, listener, octave

Constructor Summary

Constructors

Constructor and Description
InterpolatingOctaveExtremaFinder() Default constructor using BasicOctaveExtremaFinder.DEFAULT_MAGNITUDE_THRESHOLD for the magnitude threshold, AbstractOctaveExtremaFinder.DEFAULT_EIGENVALUE_RATIO for the Eigenvalue ratio threshold and DEFAULT_INTERPOLATION_ITERATIONS for the number of iterations.
InterpolatingOctaveExtremaFinder(float magnitudeThreshold) Construct with the given magnitude threshold, AbstractOctaveExtremaFinder.DEFAULT_EIGENVALUE_RATIO for the Eigenvalue ratio threshold and DEFAULT_INTERPOLATION_ITERATIONS for the number of iterations.
InterpolatingOctaveExtremaFinder(float magnitudeThreshold, float eigenvalueRatio, int numInterpolationIterations) Construct with the given magnitude and Eigenvalue thresholds andnumber of iterations.

Method Summary

Modifier and Type	Method and Description
void	process(GaussianOctave<FImage> octave) Process the provided octave.
protected void	processExtrema(FImage[] dogs, int s, int x, int y, float octSize) Perform any additional checks on the point, and then inform the listener that a point has been found.
protected void	processExtremaInternal(FImage[] dogs, int s, int x, int y, float octSize)

Methods inherited from class org.openimaj.image.feature.local.detector.pyramid.BasicOctaveExtremaFinder

beforeProcess, firstCheck

Methods inherited from class org.openimaj.image.feature.local.detector.pyramid.AbstractOctaveExtremaFinder

getCurrentScaleIndex, getOctave, isLocalExtremum, isNotEdge

Methods inherited from class org.openimaj.image.feature.local.detector.pyramid.AbstractOctaveInterestPointFinder

getOctaveInterestPointListener, setOctaveInterestPointListener

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_INTERPOLATION_ITERATIONS

public static final int DEFAULT_INTERPOLATION_ITERATIONS

Default number of interpolation iterations

See Also:

Constant Field Values

numInterpolationIterations

protected int numInterpolationIterations

Constructor Detail

InterpolatingOctaveExtremaFinder

public InterpolatingOctaveExtremaFinder()

Default constructor using BasicOctaveExtremaFinder.DEFAULT_MAGNITUDE_THRESHOLD for the magnitude threshold, AbstractOctaveExtremaFinder.DEFAULT_EIGENVALUE_RATIO for the Eigenvalue ratio threshold and DEFAULT_INTERPOLATION_ITERATIONS for the number of iterations.

InterpolatingOctaveExtremaFinder

public InterpolatingOctaveExtremaFinder(float magnitudeThreshold)

Construct with the given magnitude threshold, AbstractOctaveExtremaFinder.DEFAULT_EIGENVALUE_RATIO for the Eigenvalue ratio threshold and DEFAULT_INTERPOLATION_ITERATIONS for the number of iterations.

Parameters:

magnitudeThreshold - the magnitude threshold

InterpolatingOctaveExtremaFinder

public InterpolatingOctaveExtremaFinder(float magnitudeThreshold,
                                        float eigenvalueRatio,
                                        int numInterpolationIterations)

Construct with the given magnitude and Eigenvalue thresholds andnumber of iterations.

Parameters:

magnitudeThreshold - the magnitude threshold

eigenvalueRatio - the Eigenvalue threshold

numInterpolationIterations - the number of interpolation iterations

Method Detail

process

public void process(GaussianOctave<FImage> octave)

Description copied from interface: OctaveProcessor

Process the provided octave.

Specified by:

process in interface OctaveProcessor<GaussianOctave<FImage>,FImage>

Overrides:

process in class AbstractOctaveExtremaFinder<GaussianOctave<FImage>>

Parameters:

octave - the octave.

processExtrema

protected void processExtrema(FImage[] dogs,
                              int s,
                              int x,
                              int y,
                              float octSize)

Description copied from class: AbstractOctaveExtremaFinder

Perform any additional checks on the point, and then inform the listener that a point has been found.

Overrides:

processExtrema in class BasicOctaveExtremaFinder

Parameters:

dogs - the stack of images in this octave

s - the interest-point scale

x - the x-coordinate of the interest-point

y - the y-coordinate of the interest-point

processExtremaInternal

protected void processExtremaInternal(FImage[] dogs,
                                      int s,
                                      int x,
                                      int y,
                                      float octSize)