4 October 1999 New method for detection of dim point targets in infrared images
Author Affiliations +
There are several methods reported in the literature for detecting dim targets against slowly moving clutter. However, each method has its won advantages and disadvantages. The challenge lies in reducing the false alarm rate to an acceptable level. 'False alarm rate' defined in case of a significant size of the target in a frame may not be applicable to point-targets. This paper presents a new method for the detection of dim point-targets in the presence of the evolving clouds and heavy background clutter. Choosing a threshold for achieving constant false alarm rate is always a tricky problem. Too less a threshold may ensure detection of target pixels. But this will result in too may false targets, which limit the performance of the post-processor to trace out target paths. Too high a threshold result in fewer false alarms but the targets may also be missing out. Based on off-line studies, it has been found that a 'desirable condition' is required to limit the number of accumulated pixels not to exceed 8 percent of the total image size for post-processing. This paper present a method based on random and correlated noises which in turn selects an auto threshold that leads to the 'desired condition' for the post-processor. An effort has been made to derive an empirical formula based on random and correlated noises to obtain an auto threshold value that achieves the desirable condition. Then the incoming frames of data are then processed by a constant threshold and accumulated as total number of pixels. At the same time the track record of pixels along with frame numbers are recorded. The post-processor to filter out the false alarms uses this information. One advantage of this method is that there is no need to store all the frames to obtain the desired information. The algorithm has been tested with the available database and the results are very promising. It is assumed that most of the targets occupy a couple of pixels. Head-on moving and maneuvering targets are not considered.
© (1999) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Wei Lee New, M. J. Tan, Meng Hwa Er, and Ronda Venkateswarlu "New method for detection of dim point targets in infrared images", Proc. SPIE 3809, Signal and Data Processing of Small Targets 1999, (4 October 1999); doi: 10.1117/12.364015; https://doi.org/10.1117/12.364015

Back to Top