Illumination-Invariant Active Vision
نویسندگان
چکیده
We have developed a visual system which adapts for varying illumination. The system has three features. First, the intenaity of the image is kept constant by automatically adjusting the iris value which i s a camera parameter. Semnd, t.lw gray levels of itn image portion or the user's interest are averaged on the assumptiorl illat localized illumination changes uniformly, and the difference between the obtained gray level average and a pred~t~rnl ined reference value is calculated as an illumination variable. Third, the iris value, which zeroes the illu~nination variable, is estimated linearly I>ecause the r~lationship betwccn the iris value and the gray level averagr can be locally approximated by a linear function. TJIP system was evaluatt:d with it11 edhe dt.tectioir, wliile changing the illumination in a variety of ways. The syst rm proved capable of detecting edges more stably and r~lial,ly than w h ~ n the systcm was not used.
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