The image distance transform is a time-consuming global operation. We use optical correlation for the fast computation of binary image distance transforms. A joint transform correlator is proposed to implement the algorithm that accommodates the morphological threshold-decomposition concept. The proposed optical processor is programmable for computing Euclidean, city-block, and chessboard distance transforms in real time. Skeletonization by use of the distance transform and the rotation invariance of the Euclidean distance transform are demonstrated.
© 2000 Optical Society of America
(070.2590) Fourier optics and signal processing : ABCD transforms
(070.4550) Fourier optics and signal processing : Correlators
(200.4560) Optics in computing : Optical data processing
(200.4690) Optics in computing : Morphological transformations
Shuqun Zhang and Mohammad A. Karim, "Image Distance Transforms that Use Optical Correlation," Appl. Opt. 39, 796-802 (2000)