org.openimaj.image.feature.dense.gradient.dsift

Class ByteDSIFTKeypoint

java.lang.Object

org.openimaj.math.geometry.point.Point2dImpl

org.openimaj.feature.local.SpatialLocation

org.openimaj.image.feature.dense.gradient.dsift.ByteDSIFTKeypoint

All Implemented Interfaces:

Serializable, Cloneable, FeatureVectorProvider<ByteFV>, LocalFeature<SpatialLocation,ByteFV>, LocalFeatureVectorProvider<SpatialLocation,ByteFV>, Location, LocationProvider<SpatialLocation>, org.openimaj.io.Readable, org.openimaj.io.ReadableASCII, org.openimaj.io.ReadableBinary, org.openimaj.io.ReadWriteable, org.openimaj.io.VariableLength, org.openimaj.io.Writeable, org.openimaj.io.WriteableASCII, org.openimaj.io.WriteableBinary, Coordinate, Point2d

public class ByteDSIFTKeypoint
extends SpatialLocation

Dense SIFT keypoint with a location and byte feature vector. Also includes the energy of the feature prior to normalisation in case low-contrast features need removing.

Author:

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

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
Q	descriptor The descriptor (normalised)
float	energy The energy of the descriptor prior to normalisation; computed as the sum of descriptor values divided by the number of sample pixels used to create it (hence comparable across different window sizes).

Fields inherited from class org.openimaj.math.geometry.point.Point2dImpl

x, y

Constructor Summary

Constructors

Constructor and Description
ByteDSIFTKeypoint() Construct with the default feature vector length for SIFT (128).
ByteDSIFTKeypoint(float x, float y, byte[] descriptor, float energy) Construct with the given parameters.
ByteDSIFTKeypoint(float x, float y, float[] fdescriptor, float energy) Construct with the given parameters.
ByteDSIFTKeypoint(int length) Construct with the given feature vector length.

Method Summary

Modifier and Type	Method and Description
String	asciiHeader()
byte[]	binaryHeader()
ByteFV	getFeatureVector()
SpatialLocation	getLocation()
void	readASCII(Scanner in)
void	readBinary(DataInput in)
String	toString()
void	writeASCII(PrintWriter out)
void	writeBinary(DataOutput out)

Methods inherited from class org.openimaj.feature.local.SpatialLocation

clone, getDimensions, getOrdinate

Methods inherited from class org.openimaj.math.geometry.point.Point2dImpl

copy, copyFrom, createRandomPoint, createRandomPoint, equals, fromDoubleArray, getX, getY, hashCode, minus, setOrdinate, setX, setY, transform, translate, translate

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.openimaj.math.geometry.point.Coordinate

setOrdinate

Field Detail

energy

public float energy

The energy of the descriptor prior to normalisation; computed as the sum of descriptor values divided by the number of sample pixels used to create it (hence comparable across different window sizes). Can be used to remove low-contrast descriptors.

descriptor

public Q descriptor

The descriptor (normalised)

Constructor Detail

ByteDSIFTKeypoint

public ByteDSIFTKeypoint()

Construct with the default feature vector length for SIFT (128).

ByteDSIFTKeypoint

public ByteDSIFTKeypoint(int length)

Construct with the given feature vector length.

Parameters:

length - the length of the feature vector

ByteDSIFTKeypoint

public ByteDSIFTKeypoint(float x,
                         float y,
                         byte[] descriptor,
                         float energy)

Construct with the given parameters.

Parameters:

x - the x-ordinate of the keypoint

y - the y-ordinate of the keypoint

descriptor - the feature vector of the keypoint

energy - the energy of the keypoint

ByteDSIFTKeypoint

public ByteDSIFTKeypoint(float x,
                         float y,
                         float[] fdescriptor,
                         float energy)

Construct with the given parameters. The float version of the descriptor is converted to bytes by multiplying each bin by 512, clipping to 255 and then subtracting 128.

Parameters:

x - the x-ordinate of the keypoint

y - the y-ordinate of the keypoint

fdescriptor - the flaot version of feature vector of the keypoint

energy - the energy of the keypoint

Method Detail

getFeatureVector

public ByteFV getFeatureVector()

toString

public String toString()

Overrides:

toString in class Point2dImpl

writeBinary

public void writeBinary(DataOutput out)
                 throws IOException

Specified by:

writeBinary in interface org.openimaj.io.WriteableBinary

Overrides:

writeBinary in class SpatialLocation

Throws:

IOException

writeASCII

public void writeASCII(PrintWriter out)
                throws IOException

Specified by:

writeASCII in interface org.openimaj.io.WriteableASCII

Overrides:

writeASCII in class SpatialLocation

Throws:

IOException

readBinary

public void readBinary(DataInput in)
                throws IOException

Specified by:

readBinary in interface org.openimaj.io.ReadableBinary

Overrides:

readBinary in class SpatialLocation

Throws:

IOException

readASCII

public void readASCII(Scanner in)
               throws IOException

Specified by:

readASCII in interface org.openimaj.io.ReadableASCII

Overrides:

readASCII in class SpatialLocation

Throws:

IOException

getLocation

public SpatialLocation getLocation()

Specified by:

getLocation in interface LocationProvider<SpatialLocation>

binaryHeader

public byte[] binaryHeader()

Specified by:

binaryHeader in interface org.openimaj.io.ReadableBinary

Specified by:

binaryHeader in interface org.openimaj.io.WriteableBinary

Overrides:

binaryHeader in class SpatialLocation

asciiHeader

public String asciiHeader()

Specified by:

asciiHeader in interface org.openimaj.io.ReadableASCII

Specified by:

asciiHeader in interface org.openimaj.io.WriteableASCII

Overrides:

asciiHeader in class SpatialLocation