org.openimaj.video.processing.motion

Class MotionEstimatorAlgorithm.PHASE_CORRELATION

java.lang.Object

org.openimaj.video.processing.motion.MotionEstimatorAlgorithm

org.openimaj.video.processing.motion.MotionEstimatorAlgorithm.PHASE_CORRELATION

Enclosing class:

MotionEstimatorAlgorithm

public static class MotionEstimatorAlgorithm.PHASE_CORRELATION
extends MotionEstimatorAlgorithm

Basic phase correlation algorithm that finds peaks in the cross-power spectrum between two images. This is the basic implementation without sub-pixel accuracy.

Nested Class Summary

Nested classes/interfaces inherited from class org.openimaj.video.processing.motion.MotionEstimatorAlgorithm

MotionEstimatorAlgorithm.PHASE_CORRELATION, MotionEstimatorAlgorithm.TEMPLATE_MATCH

Constructor Summary

Constructors

Constructor and Description
PHASE_CORRELATION()

Method Summary

Modifier and Type	Method and Description
Point2d	estimateMotion(VideoSubFrame<FImage> img2sub, VideoSubFrame<FImage>... imagesSub) Calculate the estimated motion vector between images which [0] is first in the sequence and img2 which is second in the sequence.

Methods inherited from class org.openimaj.video.processing.motion.MotionEstimatorAlgorithm

requiredNumberOfFrames

Methods inherited from class java.lang.Object

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

Constructor Detail

PHASE_CORRELATION

public PHASE_CORRELATION()

Method Detail

estimateMotion

public Point2d estimateMotion(VideoSubFrame<FImage> img2sub,
                              VideoSubFrame<FImage>... imagesSub)

Calculate the estimated motion vector between images which [0] is first in the sequence and img2 which is second in the sequence. This method uses phase correlation - the fact that translations in space can be seen as shifts in phase in the frequency domain. The returned vector will have a maximum horizontal displacement of img2.getWidth()/2 and a minimum displacement of -img2.getWidth()/2 and similarly for the vertical displacement and height.

Parameters:

img2sub - The second image in the sequence

imagesSub - The previous image in the sequence

Returns:

the estimated motion vector as a Point2d in absolute x and y coordinates.