Abstract: A method and system implements a high addressability characteristic into an error diffusion process. A histogram of the image is generated and the actual background and black reference values are determined. A gray level value representing a pixel is received. The gray level value has a first resolution which corresponds to an original input resolution. The gray level value is interpolated to generate subpixel gray level values which correspond to a second resolution. The second resolution is higher than the first resolution and corresponds to the high addressability characteristic. A threshold circuit thresholds the interpolated gray level value and generates an error value as a result of the threshold using the determined background and black reference values. The error value has a resolution corresponding to the first resolution. A portion of the error value is diffused to adjacent pixels on a next scanline.

Abstract: A method and system automatically determines the width (i.e., left and right edges) of a document when it is loaded for scanning or copying. When a document is staged, the scanner collects a predetermined number scanlines of the leadedge of the document. Both first order and second order statistics of the scanner and document are then calculated based on the scanned data. The auto-width detection process is adaptive to CCD sensor output variation, document variation, and scanner variation, thus making it robust against dust in the sensor path and random fluctuations of the scanner.

Abstract: A method and system automatically determines proper background values for a document. A histogram of the document is generated and it is determined whether a background characteristic of the document is uniform. If the background is uniform, a white background value is set equal to a first calculated white peak value. If the background is non-uniform, the white background value is set equal to a second calculated white peak value. A foreground value of the document is analyzed for validity when it is determined that a background characteristic of the document is uniform. A black background value is set equal to a black peak value calculated from the histogram when it is determined that a foreground value of the document is valid.

Abstract: A printing system for rendering marks on a recording medium receives a multi-level grey scale pixel value representing a pixel having a first resolution. A screening circuit generates a screened multi-level grey scale pixel value equal to (G.sub.L -V.sub.i)+(S.sub.i -Th)*Dmp.sub.vi *Mod.sub.Eff wherein G.sub.L is the maximum grey level value of the pixel, V.sub.i is equal to the multi-level grey scale pixel value of the first resolution, S.sub.i is equal to a screen value corresponding to a position of the pixel, the image classification of the pixel and a brightness/darkness setting, The threshold value, Dmp.sub.vi is a video dependent dampening factor, and Mod.sub.Eff is a modulation multiplication factor.