To an increasing degree, equipment is available which is capable of converting photographic information into machine readable form or converting computer files into a visual image more or less resembling a half-tone picture, thus rendering photographic and other pictorial information available as data for processing by digital computers. Three major directions of effort have ensued. Necessary utility routines have been developed for managing I/O, file manipulation, and the implementation of languages to facilitate programming effort; analytical work toward character and pattern recognition, and toward parametric characterization of pictures has led to algorithms for accomplishing various sorts of mensuration and analysis; and, finally, algorithms have begun to emerge which are designed to change the appearance of a picture by modifying the file which represents it. A brief list of references to this work is given at the end of the paper, including an excellent review of the field by Lipkin and Rosenfeld.

Computer manipulation of digitized pictures

The high-speed digital computer has contributed to significant progress in the field of optics. One particular area of optics benefiting from this progress is image processing. The purpose of image processing is to aid the human observer in extracting from an image information which has been obscured by some type of degradation The numerous factors which can degrade the quality of an image in an optical system include lens aberrations, poor focus, image motion, turbulence, and diffraction. In general, the problem of obtaining good images in an optical system should be approached by minimizing these factors by careful design and by control of conditions during recording of the image, usually on photographic film. However, there are times when all factors cannot be controlled sufficiently so that the recorded image lacks the required detail for a given application. In the past little could be done in the way of improving the image once it had been recorded. Now, recently developed processing techniques allow the image to be improved after it is recorded. Although there are several different methods by which these improvements can be made, one of the most powerful and flexible utilizes the digital computer. The purpose of this paper is to describe the basic method of processing, the difficulties facing the image processor working on practical problems, and a unique image processing system devised to overcome these difficulties.

B. L. McGlamery

Papers

An on-line image processing system