Abstract: Compression apparatus is described that operates to select an optimum compression procedure to apply to received image data. The compression apparatus can be employed in a page printer having a print engine that must be provided with video data at a constant rate in order to avoid a print underrun. The page printer operates to receive print data and to convert the received print data into rasterized page strips. Some or all of these rasteized page strips can then be compressed by the compression apparatus for later conversion to video data. The compression apparatus operates to compress each received rasterized page strip by selecting a compression procedure that results in a compressed strip that will provide optimum print quality while not causing a print underrun and that is below a threshold data size.

Abstract: An alignment apparatus for use in an electrophotographic imaging device includes a first counter to count a first value of changes of a first signal, with the first value related to a first location of a photoconductor in a first direction. In addition, the alignment apparatus includes a second counter to count a second value of changes of a second signal, with the second value related to a second location of the photoconductor in a second direction substantially perpendicular to the first direction. Additionally, the alignment apparatus includes a circuit coupled to the first and the second counter to generate a change in a third signal after the first and the second counter count to, respectively, the first value and the second value.

Abstract: An apparatus includes a memory to store compressed color data and decompressed color data. In addition, the apparatus includes a decompressor arranged to receive the compressed color data from the memory and configured to generate the decompressed color data and store the decompressed color data in the memory. Furthermore, the apparatus includes a color space converter arranged to receive the decompressed color data from the memory and configured to perform a color space conversion on the decompressed color data to form converted color space data. Additionally, the apparatus includes a halftoning device arranged to receive the converted color space data and configured to perform a halftoning operation to generate halftone data. A method includes storing compressed color data in a memory and loading the compressed color data into a decompressor from the memory.

Abstract: An alignment apparatus for use in an electrophotographic imaging device includes a first counter to count a first value of changes of a first signal, with the first value related to a first location of a photoconductor in a first direction. In addition, the alignment apparatus includes a second counter to count a second value of changes of a second signal, with the second value related to a second location of the photoconductor in a second direction substantially perpendicular to the first direction. Additionally, the alignment apparatus includes a circuit coupled to the first and the second counter to generate a change in a third signal after the first and the second counter count to, respectively, the first value and the second value.

Abstract: Apparatus for writing compressed data to a storage device having multiple storage areas. The apparatus identifies one or more storage areas to receive the compressed data based upon the compression ratio of the compressed data and the characteristic transfer rates of the storage areas. The apparatus then writes the compressed data to the Identified storage areas. This is accomplished so that when the compressed data is later read, the storage device has at least a minimum output rate. The storage device may, for example, be a disk storage unit for a laser printer. The compressed data may be compressed video data describing a document to be printed.