Real-time adaptive method for noise filtering of a stream of thermographic line scans based on spatial overlapping and edge detection

Abstract

Abstract. Image filtering is a very important task in any imageprocessing system, since the output of the filtering constitutes the primary input to high-level vision, which then utilizes domain-specific knowledge to interpret and analyze the image contents. We propose a new approach to filtering the noise of a stream of thermographic line scans. The filter is designed to be applied in real time and is divided in two components: an intrascan filter and an interscan filter. The intrascan filter is based on spatial overlapping which occurs when using high acquisition rates. The interscan filter is based on edge detection and is able to adapt the way it produces the filtered output based on the detected edges. A procedure to automatically tune the parameters of the interscan filter is described and applied.The results of the proposed filters are compared to those obtained using the average and the median filter. In addition, the real-time performance of the proposed filters is analyzed by measuring the time taken by the tasks involved in their application.

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