Patent Number: 6,310,695

Title: Image registration method

Abstract: An electronic image registration system for a high-speed raster printer controller includes dedicated hardware for performing run-time registration, in both the horizontal and vertical directions, on a continuous stream of rasterized bit-map data generated by the rendering units of the raster printer controller. The registration takes place in hardware, between the rendering section of the controller and the print engine, thus allowing the registration to be performed in real-time without slowing the controller's processing speeds. The dedicated run-time electronic-image registration hardware for the vertical registration of the image includes a vertical holding register and a vertical counter. The vertical holding register is loaded by a CPU and indicates the magnitude of the vertical registration, which in turn indicates a length of delay in scan-line units before the start of the page-map's print cycle after seeing a "top-of-form" signal from the print engine. The dedicated run-time electronic-image registration hardware for the horizontal registration of the image includes a barrel-shifter, a data bus coupled to the input port of the barrel-shifter for transmitting the data stream to the barrel-shifter one block of scan-line data at a time, a history register coupled to the output of the barrel-shifter, and a logical adding device having a first addend input port coupled to the output port of the barrel-shifter and a second addend input port coupled to the output port of the history register.

Inventors: Gauthier; Forrest P. (Maineville, OH), Jovic; Dimitrije L. (Cincinnati, OH)

Assignee: Varis Corporation

International Classification: G06T 3/00 (20060101); H04N 1/40 (20060101); G06F 015/00 ()

Expiration Date: 10/30/2018