Abstract: A document processing system directs documents at a high rate of speed past an optical scanner which captures written information on the documents as video image data. The video image data is directed over a data channel to a host computer system where the data is stored on a mass data storage device for subsequent retrieval. A buffer is provided between the scanner and the data channel, which receives data a rate which varies in relation to the amount of information present on the documents. Data is extracted from the buffer at a rate which is limited by the host computer's channel transfer rate. A control means is associated with the buffer and is operable for controlling a hierarchy of actions ranging from slowing down the incoming data stream to stopping the data stream altogether in order to prevent any loss of video image data due to overfilling of the buffer.

Abstract: In order to reduce data storage and transmission bandwidth requirements, a high resolution gray scale image is represented in two separate image forms, namely, a high resolution, high sampling density black and white image and a lower resolution, lower sampling density gray scale image. Generating separate black and white and gray scale image data allows the use of either image form independently. The high resolution black and white image data and the low resolution gray scale image data may be recombined subsequently to produce reconstructed high resolution gray scale image data representing the image.

Abstract: Documents, such as bank checks, are processed at a high rate of speed on an image processing system which optically scans the documents and converts optically perceptible data on the documents into video image data. The video image data from the scanner is compressed by data compression techniques and the compressed data is sent over a high speed data channel to a high speed mass storage device which receives and temporarily stores the data. A lower speed mass data storage device, such as an optical disk, is connected for receiving at a lower data transfer rate the compressed video image data and for storing the video image data for subsequent retrieval. The system also includes real-time quality control systems for monitoring the quality of the image data to detect the existence of unacceptable image quality data and for generating a signal which can be used for immediately stopping the generation of unacceptable quality image data.