29 October 1981 Recognition Of Thermal Images: Effects Of Scan-Line Density And Signal-To-Noise Ratio
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Proceedings Volume 0274, Assessment of Imaging Systems II; (1981) https://doi.org/10.1117/12.931854
Event: Assessment of Imaging Systems: Visible and Infrared, 1981, Reading, United Kingdom
A series of psychophysical experiments was carried out in order to investigate the effects of scan-line density and pictorial noise upon the recognition of thermal images of military vehicles. The basic test material consisted of a series of 69 thermographs made in the field. The thermographs were displayed indoors using a flying spot scanner system with variable scan line density and variable amounts of noise added electronically in the scanning circuit. The experiments were carried out session-wise. In each session all 69 pictures were presented in random order with the same scan-line density and the same amount of noise. Subjects were asked to identify the vehicles out of 6 alternatives. Big differences are found in recognizability between the vehicles and even bigger differ-ences between different views of the same vehicle. Hot spot front views are most difficult. On the average an identification score of 70% is obtained at about 2 scan lines per meter (measured over the real objects), when no noise is added. The effect of noise is surprisingly small. In additional experiments it was found that the scores at a fixed scan-line density could hardly be affected by MTF-operations, if not pushed to the extreme. We perhaps may conclude that prediction models as well as design approach, should recognize scan-line density as the main parameter, to be considered first.
© (1981) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Aart van Meeteren, Aart van Meeteren, Sami Mangoubi, Sami Mangoubi, } "Recognition Of Thermal Images: Effects Of Scan-Line Density And Signal-To-Noise Ratio", Proc. SPIE 0274, Assessment of Imaging Systems II, (29 October 1981); doi: 10.1117/12.931854; https://doi.org/10.1117/12.931854

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