Acoustooptic morphological image processing with electronic feedback

Morphology is an image algebra technique whereby the shape and structure of an input object is transformed by a smaller object called the structuring element. The two most fundamental morphological operations, erosion and dilation, are usually defined in terms of set operations. Alternatively they can be understood in terms of a convolution followed by a threshold. In this paper we describe an iterative acoustooptic (AO) morphological image processor. The input to the system is displayed on a 128 × 128 magnetooptic spatial light modulator, and the system utilizes an AO Bragg cell in the Fourier plane of a coherent optical correlator to generate the desired structuring element. Thresholding is performed electronically in an image processing system. The feedback necessary for multiple erosions and dilations is provided electronically via a single computer that controls both an image processing system in the output image plane and the MOSLM.