Rangachar Kasturi wrote:This book describes some of the technical methods and systems used for document processing of text and graphics images. The methods have grown out of the fields of digital signal processing, digital image processing, and pattern recognition. The objective is to give the reader an understanding of what approaches are used for application to documents and how these methods apply to different situations. Since the field of document processing is relatively new, it is also dynamic, so current methods have room for improvement, and innovations are still being made. In addition, there are rarely definitive techniques for all cases of a certain problem.

The intended audience is executives, managers, and other decision makers whose business requires some acquaintance or understanding of document processing. (We call this group "executives" in accordance with the Executive Briefing series.) Some rudimentary knowledge of computers and computer images will be helpful background for these readers. We begin at basic principles (such as, what is a pixel?), but do not belabor them. The reader is expected not so much Document Processing and Optical Character Recognition as to have knowledge of picture processing as to have a level of comfort with the tasks that can be accomplished on a computer and the digital nature by which any computer technique operates. A grasp of the terminology goes a long way toward aiding the executive in discussing the problem. For this reason, each section begins with a list of keywords that also appears in the index. With knowledge of the terminology and whatever depth of method or system understanding that he or she decides to take from the text, the executive should be well-equipped to deal with document processing issues.

Rangachar Kasturi wrote:The book is organized in the sequence that document images are usually processed. After document input by digital scanning, pixel processing is first performed. This level of processing includes operations that are applied to all image pixels. These include noise removal, image enhancement, and segmentation of image components into text and graphics (lines and symbols). Feature-level analysis treats groups of pixels as entities, and includes line and curve detection, and shape description. The last two chapters separate text and graphics analysis. Text analysis includes optical character recognition (OCR) and page format recognition. Graphics analysis includes recognition of components of engineering drawings, maps, and other diagrams.