Single read station acquisition for character recognition

Abstract

To read characters printed on a document it is transported beneath a self-scan photocell array extending substantially the entire width of the document. Output signals from the photocells of the array are scanned by a plurality of channels, amplified and converted into a digital data format representing the character patterns. The digital data is then processed to memory electronics and search electronics to select lines of character pattern data for transmission to a character recognition unit. The search electronics compresses the character data into search segments to evaluate the top and bottom position of character lines. Further, the search electronics determines line linkages between the elements of one search segment of compressed data and the elements of the preceding search segments for future processing in a line tracker. The line tracker provides signals to extract character lines from a temporary storage for transmission to a line block memory. When the parameters of selected lines are determined by the line tracker of the search electronics the character data in the line block memory is unloaded into circuitry that functions to select data to be routed to read electronics for processing to a character recognition unit.