Dynamic pass buffer sizing

Abstract

Data describing an image to be printed on a print medium is transferred to an ink jet print head. The print head has n number of nozzles in a vertical array for sequentially ejecting vertical columns of ink droplets onto the print medium as the print head scans horizontally across the print medium. The vertical columns of ink droplets ejected during a single pass of the print head collectively comprise a swath of the image. As the data is received from a data source, a required memory space is determined which would accommodate a portion of the data describing a swath of the image to be printed using all n of the nozzles. A current available capacity of a memory device is determined and the amount of image data received from the host is determined. A portion of the data that describes a swath of the image to be printed using a number m of the nozzles is transferred to the memory device. The number m depends on the minimum of the ratio of current available capacity of the memory device to the required memory space needed to accommodate data required to print a swath using all n of the nozzles and the ratio of the image data received from the host to the amount of image data required to print a swath using all n of the nozzles. The portion of the data that describes the swath of the image to be printed using the m number of the nozzles is transferred from the memory device to the print head. The swath of the image is then printed on the print medium using the m number of the nozzles.