Abstract: Increased and potentially extreme compression of documents is achieved by reducing/remapping the dynamic range of the document image possibly together with further image analysis and pre-processing and storing the document together with a substituted table of values chosen to restore or enhance the dynamic range of the document image. Increased or extreme compression is provided notwithstanding multiple image tones (e.g. colors or grey scale levels) even at low contrast within a document, such as a personal check. Such increased compression allows document images to be maintained in rapid-access memory for extended periods without increased storage costs.

Abstract: Increased and potentially extreme compression of documents is achieved by reducing/remapping the dynamic range of the document image possibly together with further image analysis and pre-processing and storing the document together with a substituted table of values chosen to restore or enhance the dynamic range of the document image. Increased or extreme compression is provided notwithstanding multiple image tones (e.g. colors or grey scale levels) even at low contrast within a document, such as a personal check. Such increased compression allows document images to be maintained in rapid-access memory for extended periods without increased storage costs.

Abstract: Video image data received from an optical document reading system is processed by a dynamic field cut technique which utilizes the scan line as its elemental unit of data in controlling the concurrent extraction and processing of the individual fields. The field cut technique of the present invention has a chain of control instructions with a series of pointers being utilized to control the sequential processing of the control instructions and permit bypassing the control instructions for fields for which processing has been completed. By this arrangement, the number of operations necessary to separately act on a plurality of independently defined fields is reduced.