摘要:
Selective edge softening and selective edge dithering is introduced into an image representation to improve local control where halo problems are expected. Selective areas of dilation are isolated and separately dithered or halftoned, the result of which is then swapped back into or substituted for the stored original image. In this manner misregistration and color plane-to-plane interactions can be compensated for in plural image forming station architecture systems. The same technique is also valuable in monochrome systems as an aid to overcoming edge displacement and slow toner problems when the selective edge softening is selectively applied to edges which are in particular perpendicular to the fast scan direction.
摘要:
A method for rendering a raster output level determines an image position of a pixel of interest (POI) within an image. An intended raster output level, which corresponds to the POI, is received into a processing device. A final raster input level is determined as a function of the image position and the intended raster output level. The final input level and the image position are transmitted to an output device. An actual raster output level is rendered, via the output device, at a position on an output medium corresponding to the image position. The actual raster output level substantially matches the intended raster output level.
摘要:
An adaptive image enhancement filter includes a template matching module for comparing an observed pixel pattern comprising a target pixel and one or more neighboring pixels to a set of templates to determine if the observed pixel pattern matches any of the templates. The template matching module generates a match identifier signal indicating which of the templates, if any, the observed pixel pattern is found to match. Based on this match identifier, a signal generation module provides an enhanced output signal for the target pixel. The template matching and/or the signal generation modules can be independently modified to adapt to changing conditions as identified by signals identifying image attributes and marking process attributes.
摘要:
A registration system for image data in a binary image path includes a registration parameter source, such as a preprogrammed memory or a dynamic device, which provides registration parameters to correct for registration errors from a predetermined reference likely or predicted to occur during image output. A warping processor is in data communication with the registration parameter source which applies a selected registration parameter to an element of the image data resulting in a warped data element, minimizing the effects of the registration error. The system optionally includes an image reducing device which receives groups of high addressable binary image data and converts them to a single pixel. The pixel is then provided to the warping processor. The warping processor applies the selected registration parameter, either static or dynamically selected, from the registration parameter source to the averaged single pixel producing a warped data element. The warped data element is then optionally provided to a tone reproduction curve calibrator which adjusts for darkness errors induced by the warping or displacement of the warped data element. The calibrated pixel is then re-rendered by a processor which processes the calibrated pixel back into a plurality of print-ready data elements. The processor estimates quantization errors induced by the warping of the pixel positioning and disperses that error to following pixels. The print-ready data elements are provided to an image output terminal which produces a physical representation of the original binary image.
摘要:
The present invention is a method and apparatus for improving the appearance of electronic images, and more specifically, to the efficient use of template rotation within a template matching process to enhance such images. The invention reduces the number of entries that are stored in a look up table by eliminating identical patterns that differ only by the angle at which they are output. The appropriate templates are then rotated it by the required angle for output subsequent to their retrieval from the lookup table.
摘要:
Image rotation systems and methods optimally rotate high addressability binary images by transforming the high addressability image to a quasi-grayscale image having normal addressability. A degree of low-pass filtering may be used in conjunction with resampling the image in the process of generating the normal addressability image for rotation. The quasi-grayscale image is then rotated. The rotated quasi-grayscale image is then converted back to a high addressability binary image using a high addressability halftoning process. The systems and methods provide a process wherein high addressability binary images are rotated without introducing gray-level contours or pattern artifacts such as moiré. Further, the apparatus and method provide compact rotation of high addressability images. The density and edge integrity of the processed image are maintained without introducing false contours.
摘要:
Image rotation systems and methods optimally rotate high addressability binary images in a compact manner. High addressability bit pixels are clustered to form multi-bit pixels. The multi-bit pixel image is rotated +/−90°. A pixel mapping method is employed that realigns high addressability pixels within each target group of pixels in a manner that maintains edge integrity, maintains density, and does not introduce additional false contours. Information regarding neighboring pixel values is used to determine edge information about a given high addressability target pixel group. The edge information includes an edge slope and edge location of the high addressability target pixel group. Based on the rotation angle and the edge information of the pixel group, the target high addressability pixel group is mapped to a preferred pattern. After mapping to a preferred pattern, the high addressability pixel group is rotated.
摘要:
The present invention is a method and apparatus for automatic image segmentation using template matching filters. The invention generally segments differing binary textures or structures within an input image by passing one or more structures while removing other structures. More particularly, the method and apparatus segment a stored binary image using a template matching filter that is designed to pass therethrough, for example, text regions while removing halftone regions.
摘要:
A method and apparatus for the control of darkness/lightness in a digital image rendered by a printing system. The technique preferably employs templates to selectively apply different amounts of darkening (lightening) to borders of structures detected within the image dependent upon the need for darkening (lightening).
摘要:
The present invention is a method and apparatus for compensating for position error inherent in a raster output scanning printing system by adjusting the intensity of image exposure to effect a correction in the output image. The invention is particularly well suited to compensate for position errors arising from a plurality of sources by first summing the errors and then applying a single compensating adjustment to the intensity of individual scan rasters based upon the position error thereof.