Abstract: A method for processing a duplexed document having a first side with a first image and a second side with a second image includes scanning only the first side of the document under a first imaging condition to retrieve first information relating to each of the first image and the second image; scanning only the first side of the document under a second imaging condition to retrieve second information relating to each of the first image and the second image; and determining from the first information and the second information a show-through contribution of the second image with respect to the first side of the duplexed document.

Abstract: A method for descreening a scanned image includes providing an image in a color space. A target pixel is identified from a plurality of original pixels in the color space. An average value and a standard deviation value is computed for the target pixel with respect to other pixels in a sample window for each channel of the color space. For each channel in the color space an associated lookup table storing a plurality of kernel size values is selected. The average value and the standard deviation value computed for each channel is used to index the associated lookup table to select a kernel size value of the plurality of kernel size values for each channel. The kernel size value for each channel is applied to a low-pass filter to generate filtered pixel values in the color space corresponding to the target pixel, and the target pixel values of the target pixel are replaced with the filtered pixel values.

Abstract: A scanning apparatus includes a light source and a plurality of light sensors. The light source and the plurality of light sensors define at least one ultraviolet light channel and at least one visible light channel.

Abstract: A method, and an apparatus employing the method, of reducing red eye effect from image data having image attributes. In some embodiments, the method includes identifying image data with a first image attribute having characteristics of skin pixels, determining a shape of the identified image data having the first image attribute, mapping other image attributes within the determined shape, and determining a red eye presence from the other mapped image attributes.

Abstract: A method, and an apparatus employing the method, of reducing red eye effect from image data having image attributes. In some embodiments, the method includes identifying image data with a first image attribute having characteristics of red eye pixels, determining a centroid of the identified image data having characteristics of red eye pixels, defining a red eye region based on the centroid, and filling each of the pixels in the red eye region with a color determined from an equation relating to a distance between the centroid and each of the pixels.

Abstract: A system and method are described for the calibration of ink ejecting nozzles in a device including an inkjet printer and a scanner. The ejecting nozzles form one or more pens in a printhead cartridge. The method includes the steps of printing a test pattern including a plurality of patches onto a sheet of material using the ink ejecting nozzles. The sheet of material having the test pattern printed thereon is scanned with the scanner and scanned data is produced for each of the patches. The scanned data is analyzed in a control to determine a selected patch based on its color density, and the ink ejecting nozzles are calibrated based upon the analysis.

Abstract: Methods and systems of processing an image. One embodiment includes applying a controlled, adaptive histogram equalization technique to improve the quality of an image. Another embodiment may include classifying an image. Both embodiments may use a concentration ratio of an image or portions thereof.

Abstract: Methods and systems of classifying an image by use of a concentration ratio that indicates the smoothness of the distribution of a population of elements in the image or portions thereof. Alternate embodiments may include determining the concentration ratio based on luminance components, grayscale components or a histogram, use of thresholds for determing the image classifications such as text, graphic or photographic, and use of a training process for creating the thresholds that includes analyzing a set of images having known classifications.

Abstract: A method for reducing or eliminating residual error when “blank” pixels are found in the input image data is provided, such as one that can be used in printers of the type which use error diffusion as part of the halftoning process. When a blank pixel is found, the residual error may be immediately reduced in magnitude in one embodiment. In another embodiment, a “hop count” value is increased (or incremented) when a blank pixel is found, and if sufficient consecutive blank pixels exist in the input data, the hop count achieves a threshold and then either decimates or eliminates the residual error, thus limiting the migration of residual error. If a non-blank pixel is found in the input data before the threshold is achieved, the hop count is reset to zero.

Abstract: A method for reducing or eliminating residual error when “blank” pixels are found in the input image data is provided, such as one that can be used in printers of the type which use error diffusion as part of the halftoning process. When a blank pixel is found, the residual error may be immediately reduced in magnitude in one embodiment. In another embodiment, a “hop count” value is increased (or incremented) when a blank pixel is found, and if sufficient consecutive blank pixels exist in the input data, the hop count achieves a threshold and then either decimates or eliminates the residual error, thus limiting the migration of residual error. If a non-blank pixel is found in the input data before the threshold is achieved, the hop count is reset to zero.

Abstract: An image enhancement method includes steps of defining a mask for use with first image input data provided at a first imaging resolution; providing second image input data at a second imaging resolution having a first portion and a second portion; applying the mask to the first portion of the second image input data to form a corresponding first portion of second image output data having a first plurality of output pixels; and deriving from the second portion of the second image input data a corresponding second portion of the second image output data having a second plurality of output pixels, wherein each output pixel of the corresponding second portion of second image output data is based on at least one respective output pixel of the first portion of second image output data.

Abstract: A method for halftoning includes the steps of defining a first set of weight sets, and defining a second set of weight sets. A first error associated with a first pixel location of a plurality of pixel locations is diffused to a first neighboring at least one pixel location using a first weight set selected from the first set of weight sets, and a second error associated with a second pixel location of said plurality of pixel locations is diffused to a second neighboring at least one pixel location using a second weight set selected from the second set of weight sets. The first diffusing step and the second diffusing step are alternately performed along each scanline in the image to reduce visual artifacts.