Optical image processing has been concentrated chiefly upon processes such as image restoration and enhancement. A very fruitful area of digital image processing has been the field of image data compression. Since an earlier demonstration of the potential for optical processing in image data compression, research has been underway to extend the repertoire of image data compression methods suitable for optical processing. In this paper we describe the most recent results, a method for image data compression which concentrates its code bits in regions where image edge activity is not pronounced.
B. R. Hunt,
Sergio D. Cabrera,
"Optical Computations For A Spatially Adaptive Image Data Compression System," Optical Engineering 20(4), 204616 (1 August 1981). https://doi.org/10.1117/12.7972772