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, Th is the threshold value, Dmp.sub.Vi is a video dependent dampening factor, and Mod.sub.Eff is a modulation multiplication factor. An interpolator converts the screened multi-level grey scale pixel value to a second resolution, the second resolution being higher than the first resolution, and a binarization circuit binarizes the converted multi-level grey scale pixel value so as to output a binary signal and an error value, the error value having a resolution equal to the first resolution.

Abstract: A method and system assigns an image classification to a multi-level grey scale pixel value. The multi-level grey scale pixel value is modified based on an error generated by previously processed pixels and the image classification of the multi-level grey scale pixel and processed based on the assigned image classification to reduce the number of grey levels in the multi-level grey scale pixel value. An error is generated based on the processing of the modified multi-level grey scale pixel value and a portion of the error is diffused to a next pixel in a fastscan direction and a remaining portion of the error is diffused to pixels in a slowscan direction. The modified multi-level grey scale pixel value referred above includes an error from the previously processed neighboring pixels if the current pixel is classified as being processed as an error diffused pixel.

Abstract: A fluorescent light source includes a fluorescent lamp, lamp bases attached to opposite ends of the fluorescent lamp, and an electrically insulating substrate connected to the fluorescent lamp. A heating element is positioned on the fluorescent lamp, and a first and second pair of power traces are formed on the electrically insulating substrate. The first pair of power traces are connected to the heating element to provide power thereto. The second pair of power traces are connected to a pair of electrical conductors that provide power to the fluorescent lamp. This fluorescent lamp can be used in a replaceable fluorescent light source unit for a document scanner. The replaceable fluorescent light source unit includes a housing, lamp base receiving members attached to the housing, and registration notches to properly align the fluorescent lamp. Lastly, the fluorescent lamp source includes light blocking material to provide a uniform illumination profile along the length of the lamp.

Abstract: A process eliminates pattern shifting artifacts in a printed image by perturbing a threshold/image signal value relationship when a multi-level grey level is binarized. The process utilizes a programmable multi-level grey signal modifying circuit for modifying the multi-level grey signal by a predetermined value according to its grey level. The modified multi-level grey signal is binarized to a binary pixel signal according to a relationship between the modified multi-level grey signal and a threshold value. The process further generates an error corresponding to the relationship and diffuses the error to neighboring pixels. The multi-level grey signal is modified with either random noise multiplied by a grey level dependent coefficient or by a predetermined value from a checkerboard or vertical line pattern. The value from the pattern is dependent upon the grey level and pixel location of the image data.

Abstract: A system and method generates a histogram of a scanned image by determining a number of pixels of the image to be scanned to generate the histogram. It is then determined whether the determined number of pixels is less than or equal to a capacity of a histogram buffer. The image is scanned to generate pixels having grey values associated therewith and a portion of the generated pixels is stored in the histogram buffer if it is determined that the number of pixels exceeds the capacity of the histogram buffer, thereby generating a histogram of the image.

Abstract: A method and system enables an assignment of a feature value from a set of preset feature values for a copy operation to be performed on a reprographic system The system displays a first screen on a user interface associated with the reprographic system, the first screen displaying a plurality of activatable areas corresponding to a subset of the set of preset feature values and an activatable area corresponding to a second screen associated with the set of preset reduction enlargement values. The system further determines if the activatable area corresponding to the second screen is engaged and displays the second screen on the user interface associated with the reprographic system the activatable area corresponding to the second screen is engaged, the second screen displaying a plurality of activatable areas such that each preset feature value within the set of preset feature values has an activatable area associated therewith.

Abstract: A system generates image background and black threshold grey values associated with an image. The system includes a histogram buffer and a peak and valley detection circuit, operatively connected to the histogram buffer, to determine a first grey value having a peak frequency associated with a background, a second grey value having a peak frequency associated with a black threshold, and a third grey value having a minimum frequency associated with a histogram of the image. A quarter peak detection circuit, operatively connected to the histogram buffer, determines a fourth grey value having a frequency equal to one quarter of the peak frequency associated with the first grey value and a fifth grey value having a frequency equal to one quarter of the peak frequency associated with the second grey value.

Abstract: A method and system generates a histogram from a scanned image by creating a sample window defined by a number of scanlines to be sampled, a number of leading scanlines to be skipped in a slowscan direction before sampling, a number of leading pixels to skip in a fastscan direction before sampling begins, and a number of pixels within a scantine to be sampled. It is then determined if a number of pixels in the sample window is greater than a capacity of a histogram buffer. If it is determined that the number of pixels in the sample window is greater than the capacity of the histogram buffer subsample windows are created within the sample window.

Abstract: A filter includes a plurality of one-dimensional first dimension filters operating in a first dimension, each of the filters operating on the digital image data in accordance with predetermined filter coefficients to produce a one-dimensional output signal. The filter also includes a plurality of one-dimensional filters, operating in a second, distinct dimension, each one-dimensional second dimension filter receiving output signals from one of the plurality of the first dimension filters and operating on the received output signals in accordance with predetermined filter coefficients to produce second filtered output signals therefrom. A weighting circuit is operatively connected to the one-dimensional second dimension filters to modify each of the produced second filtered output signals according to weighting coefficients.

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, Th is the threshold value, Dmp.sub.vi is a video dependent dampening factor, and Mod.sub.Eff is a modulation multiplication factor. An interpolator converts the screened multi-level grey scale pixel value to a second resolution, the second resolution being higher than the first resolution, and a binarization circuit binarizes the converted multi-level grey scale pixel value so as to output a binary signal and an error value, the error value having a resolution equal to the first resolution.

Abstract: A process eliminates pattern shifting artifacts in a printed image rendered using a hybrid high addressable error diffusion process by perturbing a threshold/image signal value relationship when a multi-level grey level is binarized. The process utilizes a programmable multi-level grey signal modifying circuit for modifying the multi-level grey signal by a predetermined value according to its grey level. The modified multi-level grey signal is binarized to a binary pixel signal according to a relationship between the modified multi-level grey signal and a threshold value. The process further generates an error corresponding to the relationship and diffuses the error to neighboring pixels. The multi-level grey signal is modified with either random noise multiplied by a grey level dependent coefficient or by a predetermined value from a checkerboard or vertical line pattern. The value from the pattern is dependent upon the grey level and pixel location of the image data.

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.

Abstract: In an auto-fitting mode, a scanner prescans an input document to determine the location and size of an image within the input document. The area of the image is defined in terms of a rectangular area encompassing all area of the input document where the reflectance of the image data is less than 20% of the reflectance value of the input documents background. Once the image area has been defined, a magnification factor is calculated. The input document is then rescanned applying the calculated magnification factor and properly registered so that the image area can be centered when it is rendered on to the desired output paper. If the image area detected is such that the longer side of the rectangular area does not have the same orientation as the desired output paper, the image is automatically rotated prior to the magnification and registering processes. The magnification factor can be calculated either anamorphically or isotropically.

Abstract: A system and method digitally scans a document using a high reflectance mode and a low reflectance mode. Initially, a platen cover provides a low reflectance background around the document and the scanner scans the low reflectance background and document to determine an edge of the document or to retrieve other image characteristics of the document. Subsequently, the platen cover changes so as to provide a high reflectance background around the document. The scanner then scans the high reflectance background and the document and produces digital image data relating to an image on the document.

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, Th is the threshold value, Dmp.sub.vi is a video dependent dampening factor, and Mod.sub.Eff is a modulation multiplication factor. An interpolator converts the screened multi-level grey scale pixel value to a second resolution, the second resolution being higher than the first resolution, and a binarization circuit binarizes the converted multi-level grey scale pixel value so as to output a binary signal and an error value, the error value having a resolution equal to the first resolution.

Abstract: A method backfills areas of an image with synthesized textures. This is realized by selecting a texture exemplar from an image and identifying an area of the image to be backfilled. An estimate of the synthesized texture is generated and predetermined spatial domain constraints are applied to the estimate. The spatially constrained estimate is operated upon by a Fourier transform to create a spectral function. Predetermined spectral domain constraints are applied to the spectral function and an an inverse Fourier transform is performed thereon to produce a synthesized texture. The synthesized texture is inserted into the area of the image to be backfilled if it is determined to be adequate. If the synthesized texture is inadequate, the synthesized texture is put through the synthesis process again until the the texture is adequate for backfilling.

Abstract: A system and method electronically image process a pixel belonging to a set of digital image data with respect to a membership of the pixel in a plurality of image classes. This process uses classification to determine a membership value for the pixel for each image classes and generates an effect tag for the pixel based on the fuzzy classification determination. The pixel is image processed based on the membership vector of the pixel. The image processing may include screening and filtering. The screening process screens the pixel by generating a screen value according to a position of the pixel in the set of digital image data; generating a screen amplitude weighting value based on the values in the membership vector for the pixel; multiplying the screen value and the screen amplitude weighting value to produce a modified screen value; and adding the modified screen value to the pixel of image data.

Abstract: A monochromatic scanning system includes an illumination system, a document staging system, an optical lens system, a photosensing system to convert light to electrical signals and a color drop-out filter. The illumination system illuminates an original image to be scanned in the document staging system and the optical lens system directs light reflected from the original image to be scanned onto the photosensing system. The color drop-out filter is located in an optical path between the original image to be scanned and the photosensing system such that the color drop-out filter allows a predetermined range of wavelengths to pass therethrough and a range of wavelengths associated with infrared radiation to pass therethrough. this enables the monochromatic scanning system to have drop-out capability by merely substituting the color drop-out filter without further modifications to the scanning system.

Abstract: An error diffusion process adds an error value to an input grey image value to produce a modified input grey image value before comparing the modified input grey image value with a predetermined threshold value. A rendering value and error is generated based on the comparison. An error equal to the modified input grey value is generated when the modified input grey value is less than the predetermined threshold value, and an error equal to the modified input grey value minus a black reference value is generated when the modified input grey value is equal to or greater than the predetermined threshold value. This error value is further compensation for pixel growth when the output of the previously processed pixel is not equal to the output of the presently processed pixel.

Abstract: A method and system electronically fuzzy classify a pixel belonging to a set of digital image data with respect to a membership of the pixel in a plurality of image classes. This process determines a fuzzy classification of the pixel and generates an effect tag for the pixel based on the fuzzy classification determination. Each class is defined by a set of heuristic rules such that the image classes are non-mutually exclusive. The heuristic rules are a set of conditions that define the membership value of the pixel within a certain class, thereby allowing a pixel to have a membership value in every possible image class.