Abstract: An apparatus for and method of truncating images during data compression. The present invention truncates an image when the memory requirements for the compressed image exceeds a predetermined threshold. However, unlike prior art systems, the present invention contemplates replacing all of the pixels that are eliminated by the truncation process with a series of "0's" thereby "white filling" the truncated portion of the image. The present invention avoids the disadvantages in the prior art by ensuring that the truncated image contains the same number of pixels as a non-truncated image. Further, the data extent of the truncated image may be the same as a non-truncated image. Finally, the resulting images, either non-truncated images or, if necessary, truncated images, may be stored in a preselected memory size.

Abstract: A method and apparatus for the transposition of obtained video image data. This video image data originally comprises a plurality of columns, containing a plurality of pixels therein. Each of these columns uniquely corresponds to a vertical segment of the document being scanned. These vertical columns of data are then placed into an external memory and outputted therefrom, by a transposer controller, which causes the output to comprise pixel data contained in the rows of the original vertical columns input thereto.

Abstract: A pipelined image processor is disclosed which contains a diagnostic apparatus which, under normal processing conditions, is coupled to and is in communication with resequencer, image processor, and transposer/compressor assemblies contained within the pipelined image processor. The diagnostic apparatus of this invention causes a diagnostic test pattern to be sent to the re-sequencer and image processor entities of the pipelined image processor and monitors the response thereof. This response is then used to detect faults which have occurred in these entities.