The Paper's Abstract of The 3rd
International Conference on Imaging Science and Hardcopy
　

　

Evaluation of Image Noise Using Psychophysical RMS Granularity

　
　 　

May 26-29,1998
Chongqing China

Hitoshi Kanamori, Yoshiyuki Asai, Yoshiaki Oazki,
 Hideaki Kubota and Masao Matsumoto

Fukui University of Technology  
29 Shimogamo-Kitazono-Cho Saky-K-ku Kyoto 606, Japan  
Tel: (+81)75-781-7685,  Fax: (+81)75-781-7685
　 Abstract:
　    The psychophysical RMS (root mean square) granularity  σp was proposed for the evaluation of image noise. The value of σp was calculated from the Wiener spectrum of the image noise and the frequency dependence of the minimum perceptible contrast, which expressed a psychophysical property of human vision. Both of the Wiener spectra and the frequency dependence were determined using our new method. Examples were presented for several typical X-ray imaging systems. For each system, Physical RMS values σp and our psychophysical RMS values σp of noise patterns in samples having several uniform densities wee respectively arranged in descending orders, and corresponding orders in density were decided. The two orders in the density were compared with the subjective rating result arranged in descending order of the perceptibility of the noise. The density dependence of σp was in close agreement with the results of subjective rating that (1) the most perceptible density was 1.0 and (2) the perceptibility at density 2.5 was much worse than that at 0.6. Whereas the physical RMS granularity did not correlate with the results of subjective rating.

　

中国复印科学与工程学会
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