Research On Raster Image Processor With Virtual Instrument

Raster image processor (RIP) is core of prepress, which determines the composing system’s quality, being used to interpret images, graphs and texts in digital pages into binary dot matrixes that a printer can read and control printer to record in paper or other mediums.Referring to two patents of" a direct printing method on prefabricated mini dot carved plate" and " a direct printing method based on intelligent screening of associated logic" and characteristics of direct printing, with the virtual instrument technology, a unique RIP system for prefabricated mini dot carved plate is designed and implemented with virtual instrument (VI) technology on Lab VIEW software development environment.Based on printing theory, problems of traditional RIP used in direct printing was analyzed and improved with virtual instrument to get suitable for direct printing in this paper. RIP was divided into three modules as file reading, screen processing and data output, which worked in pipeline sequentially. Image data was send out as control signals through standard VI DAQ short for data acquisition device, to drive the high-pressure discharge circuit to get the image information carved on print media. That’s one of the innovations in this issue. According to the feature of image screening, on the parallel accelerating theory of serial algorithm, the execution of digital screening was adjusted to reduce data storage and increase computing speed. That’s another innovation of this issue. The "preset database screening" base on logic correlation of multi-pixels was implemented with VI, and its parallel algorithm was also used, which effectively promoted the screening efficiency. Comparative experiments were set to prove the performance of the direct printing RIP, and the algorithm adjusted effective.