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SwisTrack/Components/MotionTemplateParticleDetector

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Description

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This isn't actually a tracker but a particle detecter. It emits particles when there is motion in the image, calculated by finding gradients on frame-differences of images over multiple timescales. See the OpenCV book for more information. It also associates the particles with a color histogram if it's given a foreground model in mDataStructureImageBinary.

Parameters

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Note: I use default values for all parameters. Read the openCV book and documentation for more details - I wrote this component following the section in the openCV book on motion templates.

DiffThreshold

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Threshold to use for frame differencing.

MhiDuration

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passed to cvUPdateMotionHistory. "Maximal duration of motion track in the same units as timestamp."

SegmentThreshold

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passed to cvSegmentMotion. "Segmentation threshold; recommended to be equal to the interval between motion history "steps" or greater. "

MaxTimeDelta

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passed to cvCalcMotionGradient. "The function finds minimum (m(x,y)) and maximum (M(x,y)) MHI values over each pixel (x,y) neighborhood and assumes the gradient is valid only if min(delta1,delta2) <= M(x,y)-m(x,y) <= max(delta1,delta2)."

MinTimeDelta

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passed to cvCalcMotionGradient. "The function finds minimum (m(x,y)) and maximum (M(x,y)) MHI values over each pixel (x,y) neighborhood and assumes the gradient is valid only if min(delta1,delta2) <= M(x,y)-m(x,y) <= max(delta1,delta2)."