Tracking Subpixel Targets with Critically Sampled Optics

James Lotspeich, Mathias Kolsch


In many remote sensing applications, the area of a scene sensed by a single pixel can often be measured in squared meters. This means that many objects of interest in a scene are smaller than a single pixel in the resulting image. Current tracking methods rely on robust object detection using multi-pixel features. A subpixel object does not provide enough information for these methods to work. This paper presents a method for tracking subpixel objects in image sequences captured from a stationary sensor that is critically sampled. Using template matching, we make a Maximum a Posteriori estimate of the target state over a sequence of images. A distance transform is used to calculate the motion prior in linear time, dramatically decreasing computation requirements. We compare the results of this method to a track-before-detect particle filter designed for tracking small, low contrast objects using both synthetic and real-world imagery. Results show our method produces more accurate state estimates and higher detection rates than the current state of the art methods at signal-to-noise ratios as low as 3dB.


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Paper Citation

in Harvard Style

Lotspeich J. and Kolsch M. (2013). Tracking Subpixel Targets with Critically Sampled Optics . In Proceedings of the 2nd International Conference on Pattern Recognition Applications and Methods - Volume 1: ICPRAM, ISBN 978-989-8565-41-9, pages 375-381. DOI: 10.5220/0004263903750381

in Bibtex Style

author={James Lotspeich and Mathias Kolsch},
title={Tracking Subpixel Targets with Critically Sampled Optics},
booktitle={Proceedings of the 2nd International Conference on Pattern Recognition Applications and Methods - Volume 1: ICPRAM,},

in EndNote Style

JO - Proceedings of the 2nd International Conference on Pattern Recognition Applications and Methods - Volume 1: ICPRAM,
TI - Tracking Subpixel Targets with Critically Sampled Optics
SN - 978-989-8565-41-9
AU - Lotspeich J.
AU - Kolsch M.
PY - 2013
SP - 375
EP - 381
DO - 10.5220/0004263903750381