US Patent 7522760 Method for inspecting document images

A method for processing document image data wherein the quality of the document image is determined by examination of a vital document area includes determining a confidence level for the document by calculating two or more confidence factors for each vital document area. These confidence levels include calculations based on number, mass, and quality of identified characters within the vital area, the distribution of pixels horizontally across the document, and empirically determined norms for image density and distribution. The confidence levels are combined to give a confidence level for the document image quality.