Optical Image Segmentation Using Wavelet Correlation.

摘要

This research introduces an optical method of segmenting potential targets using wavelet analysis. Implementation of an optical Harr wavelet is fulfilled using a magneto-optic spatial light modulator (MOSLM). Two methods of controlling wavelet dilation are explored: (1) spatial filtering of a ternary modulated MOSLM; (2) a single aperture positioned in front of a binary modulated MOSLM. Segmentation is performed through Vander Lugt correlation of a binarized image with a binarized optical wavelet. Three different image binarization methods are investigated for use in the correlation scheme: (1) average pixel value over an entire scene; (2) localized 4 x 4 pixel average followed by an average pixel value over the remaining scene; (3) localized 3 x 3 pixel average ANDed with an energy pixel value over the entire scene. Frequency-plane masks necessary for the correlation process are generated using thermal holography. Results show image segmentation for six possible experimental methods comprised of wavelet dilation and binarization techniques. The most successful correlation design used a single aperture to control wavelet dilation and binarization based on a localized 4 x 4 pixel average followed by an average pixel value over the remaining scene. (Author)