org.openimaj.image.feature.local.aggregate

Class PyramidSpatialAggregator<T,AGGREGATE extends FeatureVector & Concatenatable<AGGREGATE,AGGREGATE>>

java.lang.Object

org.openimaj.image.feature.local.aggregate.PyramidSpatialAggregator<T,AGGREGATE>

Type Parameters:

T - Primitive array type of the backing array of each local feature

AGGREGATE - Type of the aggregate FeatureVector produced

All Implemented Interfaces:

SpatialVectorAggregator<ArrayFeatureVector<T>,SpatialLocation,Rectangle>

public class PyramidSpatialAggregator<T,AGGREGATE extends FeatureVector & Concatenatable<AGGREGATE,AGGREGATE>>
extends Object
implements SpatialVectorAggregator<ArrayFeatureVector<T>,SpatialLocation,Rectangle>

A PyramidSpatialAggregator performs spatial pooling of local features by grouping the local features into fixed-size spatial blocks within a pyramid, and applying a VectorAggregator (i.e. a BagOfVisualWords) to the features within each block before combining the aggregated results into a single vector (by passing through the blocks in a left-right, top-bottom fashion over the pyramid levels from the top down).

Author:

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

Field Summary

Fields

Modifier and Type	Field and Description
protected VectorAggregator<ArrayFeatureVector<T>,AGGREGATE>	innerAggregator

Constructor Summary

Constructors

Constructor and Description
PyramidSpatialAggregator(VectorAggregator<ArrayFeatureVector<T>,AGGREGATE> innerAggregator, int... numBlocks) Construct with the given aggregator and number of blocks per level.
PyramidSpatialAggregator(VectorAggregator<ArrayFeatureVector<T>,AGGREGATE> innerAggregator, String description) Construct with the given aggregator and pyramid description (i.e.

Method Summary

Modifier and Type	Method and Description
AGGREGATE	aggregate(List<? extends LocalFeature<? extends SpatialLocation,? extends ArrayFeatureVector<T>>> features, Rectangle bounds) Aggregate the given features into a vector.
protected static String	levelsToString(boolean[][][] levels)
protected static boolean[][][]	parseLevelsAdvanced(String description)

Methods inherited from class java.lang.Object

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

Field Detail

innerAggregator

protected VectorAggregator<ArrayFeatureVector<T>,AGGREGATE extends FeatureVector & Concatenatable<AGGREGATE,AGGREGATE>> innerAggregator

Constructor Detail

PyramidSpatialAggregator

public PyramidSpatialAggregator(VectorAggregator<ArrayFeatureVector<T>,AGGREGATE> innerAggregator,
                                String description)

Construct with the given aggregator and pyramid description (i.e. "1x1-2x2-4x4").

Parameters:

innerAggregator - the aggregator

description - the pyramid description

PyramidSpatialAggregator

public PyramidSpatialAggregator(VectorAggregator<ArrayFeatureVector<T>,AGGREGATE> innerAggregator,
                                int... numBlocks)

Construct with the given aggregator and number of blocks per level.

Parameters:

innerAggregator - the aggregator

numBlocks - number of blocks (in X and Y) for each level of the pyramid

Method Detail

parseLevelsAdvanced

protected static boolean[][][] parseLevelsAdvanced(String description)

levelsToString

protected static String levelsToString(boolean[][][] levels)

aggregate

public AGGREGATE aggregate(List<? extends LocalFeature<? extends SpatialLocation,? extends ArrayFeatureVector<T>>> features,
                           Rectangle bounds)

Description copied from interface: SpatialVectorAggregator

Aggregate the given features into a vector. The features are assumed to have spatial locations within the given bounds; typically this might be the bounds rectangle of the image from which the features were extracted.

Specified by:

aggregate in interface SpatialVectorAggregator<ArrayFeatureVector<T>,SpatialLocation,Rectangle>

Parameters:

features - the features to aggregate

bounds - the bounds in which the features were extracted

Returns:

the aggregated vector