Abstract Noise equivalent temperature difference (NETD) is an important parameter of infrared thermal imager, which can reflect the noise characteristics of the infrared detector. On the basis of eliminating invalid pixels, the image of the thermal imager raw data is preprocessed by linear filtering, nonlinear filtering, histogram equalization and multi-scale image enhancement. Using the direct observation of the image quality and image details by the experimenter as the qualitative criterion and the noise equivalent temperature difference as the quantitative criterion to comprehensively evaluate the advantages and disadvantages of the image preprocessing algorithm. It is found through experiments that the multi-scale image enhancement method after linear filtering can make the image details clearer, and the noise equivalent temperature difference is reduced by about 25.9%, which is the most suitable image preprocessing method for experimental infrared camera.
GAO Yi-fan,CAI Jing,ZHANG Xue-cong, et al. Research on Image Preprocessing Method of Infrared Camera Based on NETD[J]. Acta Metrologica Sinica, 2019, 40(6): 1020-1024.
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2019, Vol. 40 
