Abstract: A method and apparatus are provided for compensating for spatial non-uniformities in a printer by deriving a true spatial non-uniformity tone response curve (TRC) that characterizes the printer in terms of color output variation for each addressable pixel location in a spatial range. The “true average” tone response curve is determined for a color channel. A prediction of the true response as a function of the spatial location is derived by printing and scanning a specially designed halftone-independent target of binary patterns. The predicted tone response curve for each color channel and halftone is predicted using a binary printer model, wherein the “predicted tone response curve” provides a model based approximation of the actual response for each addressable pixel location in the spatial range. Also stored is an “average predicted tone response” by averaging the “predicted tone response curve” over the spatial range of the printer.

Abstract: A model-based method and apparatus for characterizing the performance of a printing device comprising printing a target set of patches with the device and measuring device response when the target is set; compiling a LUT from the target set and measured response; and representing the LUT as a tensor. Tensor decomposition/parallel factor analysis is employed for compacting the tensor representation of the LUT.

Abstract: A model-based halftone independent method for characterizing a printer equipped with a plural of halftone screens comprises: printing a target set of basic patches comprised of a fundamental binary pattern independent of a halftone screen; measuring true color printer response from the target set; modeling a halftone independent characterization of the printer with the mathematical transformation using the measured response; modeling a first halftone dependent characterization of the printer with the mathematical transformer to generate a first predicted result using a selected halftone screen; comparing a measured response of the printer using the halftone screen with the predicted result to define a correction factor corresponding to the halftone screen; and modeling a halftone dependent characterization of the printer using a predicted response of the fundamental binary pattern and the correction factor.

Abstract: Systems and methods are described for halftone independent temporal color drift correction, particularly for correction in hi-addressability xerographic printers. For example, a method includes printing target patches, including two resolutions, measuring printer response from the target patches, and modeling the printer using a transformation to define a correction factor, and a predicted response.

Abstract: What is disclosed is a system and method for performing a background deletion that exploits both local and global context to remove background and other white space between objects with the aim of retaining structural relationships between objects in the document. A document image is received and seams are carved through the image. Seams composed of uniform background pixels are identified. Adjacent seams containing background pixels are collected into groups of seams. The background seam groups are classified according to their widths. A target number of seams to be removed for each background seam group is then determined based on the classification. Seam groups which are wider will have at least the same or a greater target number of seams to be deleted therefrom than will seam groups of narrower widths. The document image is then resized by deleting seams from the seam groups based on the assigned target number.

Abstract: What is disclosed is a method for iterative seam selection in an image resizing system utilizing a seam carving technique. In one embodiment, an importance map is generated for a received source image. Seams are carved through the image from one edge to an opposite edge. An energy is computed for each seam based on pixel importance values. A distance is computed from each seam to a previously selected seam. A weighting for each seam is computed using a defined weighting function and the calculated seam distances. The weighting is applied to the energy of each seam produce a revised energy for each seam. A seam is selected based on the produced revised energy. The image is resized at a location of the selected seam. The process repeats until the image has been resized to a desired target output dimension. In such a manner, unnatural image resizing results are avoided.

Abstract: What is disclosed is a novel system and method for performing spatial gamut mapping on a received input color image having a plurality of pixels. A standard gamut-mapping algorithm is applied to the input color image to produce a gamut-mapped color image. A difference is computed between a selected channel of the input color image and the gamut-mapped image to produce a difference image. A local measure of complexity is derived for a given pixel in the difference image. One or more parameter values of a spatial bilateral filter are obtained from a lookup table based on the computed local measure of complexity. The spatial bilateral filter is applied, using the obtained parameter values, to the current pixel of the difference image to produce a modified pixel in a modified difference image. Thereafter, a modified gamut-mapped color image is obtained from the modified difference image and the gamut-mapped color image.

Abstract: A method and system for automatically determining an optimal re-training interval for a fault diagnoser based on online monitoring of the performance of a classifier are disclosed. The classifier generates a soft measure of membership in association with a class based on a training data. The output of the classifier can be utilized to assign a label to new data and then the members associated with each class can be clustered into one or more core members and potential outliers. A statistical measure can be utilized to determine if the distribution of the outliers is sufficiently different than the core members after enough outliers have been accumulated. If the outliers are different with respect to the core members, then the diagnoser can be re-trained; otherwise, the output of the classifier can be fed to the fault diagnoser.

Abstract: A dimensionality reduction method and system for efficient color transform compression is disclosed. A multi-dimensional color transform with an n-dimensional input color space can be received. A projection operator can be derived and applied to the n-dimensional input color space to form a k-dimensional input color space. A functional approximation can be designed to the n-dimensional input color space and can be evaluated on the k-dimensional input color space to form an m-dimensional output color space. The projection operator and the approximation function can be combined to form a compressed transform by mapping the n-dimensional input color space to m-dimensional output color space. Such an approach provides a significant reduction in size of the color profile with respect to storage and speeds-up real-time computation.

Abstract: A method automatically determines a workflow for a print job via analysis of PDF documents is disclosed. A job synopsis comprising hashed information of a historical print job's document content along with a PDF document-level and object-level metadata and information about workflow nodes and parameters can be stored in a database. The job synopsis of a new incoming print job can then be compared to the historical print job synopses database. If the new print job matches the historical print job within a certain predefined similarity limit, then workflow and parameter information associated with the historical job can be utilized to augment an initial workflow for the incoming print job.

Abstract: A system and method for characterizing color separation misregistration of a multi-color printing system utilizing a broadband multi-channel scanning module, such as an RGB scanner, are provided. The system and method include generating a spectral reflectance data structure corresponding to a broadband multi-channel scanning module. The spectral reflectance data structure includes at least one parameter. The at least one parameter may correspond to the broadband multi-channel scanning module and/or a printing module. The system and method further provide for calibrating a spectral-based analysis module by utilizing the spectral reflectance data structure. The system and method also include characterizing color separation misregistration utilizing the calibrated spectral-based analysis module by examining at least one plurality-separation patch.

Abstract: What is disclosed is a system and method for searching a repository of documents containing images using an image as a query. The present method enables the adjustment of a threshold level through a no-reference quality assessment of the query image which produces an estimated measure of quality for the image. For each image in each document in the repository, a distance is computed between a hash value of each image extracted from the document and the hash value of the query image. Documents are flagged as possible matches if the computed distance is less than the adjusted threshold. Documents flagged as a result of the search are retrieved and provided to the user. The present method can be used along or as an adjunct to text-based search techniques. Other embodiments are provided.

Abstract: A method and apparatus are provided for compensating for spatial non-uniformities in a printer by deriving a true spatial non-uniformity tone response curve (TRC) that characterizes the printer in terms of color output variation for each addressable pixel location in a spatial range. The “true average” tone response curve is determined for a color channel. A prediction of the true response as a function of the spatial location is derived by printing and scanning a specially designed halftone-independent target of binary patterns. The predicted tone response curve for each color channel and halftone is predicted using a binary printer model, wherein the “predicted tone response curve” provides a model based approximation of the actual response for each addressable pixel location in the spatial range. Also stored is an “average predicted tone response” by averaging the “predicted tone response curve” over the spatial range of the printer.

Abstract: Systems and methods are described that facilitate reducing a number of patches used in characterizing a color halftone printer via a binary color printer model. A binary printer model involves printing of a fundamental set of color binary patterns that encompass all possible halftone outputs. A k-center clustering technique is employed to automatically find and eliminate redundancies in the initial set of binary color patterns. Once the number of patches is reduced to an acceptable number, a multiplicative reflectance model is applied that better approximates the physical process and therefore improves accuracy.

Abstract: This disclosure provides methods, apparatus and systems for performing image processing regression for approximating multidimensional color transformation. According to an exemplary method, a shaping matrix is selected to minimize a cost function associated with a local linear regression representation of the color transformation.

Abstract: What is disclosed is a novel system and method for content-aware resizing of a digital image. To take advantage of the characteristics of various importance maps generated for the image using different operators such as, for example, gradient, entropy, probabilistic operators, and the like, a method is provided herein for combining generated pixel importance maps. The present method uses a weighted combination of pixel importance maps—one corresponding to each image operator, to produce a hybrid map for all the image. The image can then be resized based on this hybrid map. The present method provides a high degree of image resizing flexibility and has broad applicability across differing classes of images and applications such as display, printing, packaging, and other document image processing software performing document layout, image personalization, and the like.

Abstract: What is disclosed is a system and method for encoding and decoding data in a color barcode pattern using dot orientation and color separability. The spectral (wavelength) characteristics of the CMY colorants, commonly used in digital printing, and those of RGB sensors are exploited to achieve high capacity data embedding rates in color barcodes. The present method embeds independent data in two different printer colorant channels using dot orientation modulation. In the print end, dots of two colorants occupy the same spatial region. At the detector end, by using the complementary sensor channels to estimate the colorant channels, data is recovered in each colorant channel. The method approximately doubles the capacity of encoding methods based upon a single colorant channel and enables embedding rates which match or exceed that of other hardcopy barcodes known in the arts. The method is robust against inter-separation misregistration with a small symbol error rate.

Abstract: A system for generating one or more new hardcopy prints from an electronic file comprising original digital image data, wherein the new hardcopy print(s) match a legacy hardcopy previously generated from the original digital image data of the electronic file, even when the legacy hardcopy was printed from an “enhanced” or “tuned” version of the original image data. The original image data and scanner data derived by scanning the legacy hardcopy are used to identify corresponding areas of constant color in the original data and the legacy hardcopy. The corresponding color areas are represented in a colorimetric color space and the original data color values are adjusted to match the legacy hardcopy color values. The adjusted data are used to print a new hardcopy.

Abstract: The predicted tone response curve for each color channel and halftone is predicted using a binary printer model and stored, wherein the “predicted tone response curve” provides a model based approximation of the actual response for the printer for each addressable pixel location in the spatial range. Also stored is an “average predicted tone response” by averaging the “predicted tone response curve” over the spatial range of the printer. With the “true average” tone response curve, the “predicted tone response curve”, and the “average predicted tone response curve”, an estimate of the true tone response curve for the color channel can then be mathematically obtained, wherein the true tone response curve defines a predicted actual response for the printer for each addressable print location in the spatial range. The “predicted” and “average” tone response curves are obtained using the 2×2 binary printer model.

Abstract: What is disclosed is a system and method for encoding and decoding data in a color barcode pattern using dot orientation and color separability. The spectral (wavelength) characteristics of the CMY colorants, commonly used in digital printing, and those of RGB sensors are exploited to achieve high capacity data embedding rates in color barcodes. The present method embeds independent data in two different printer colorant channels using dot orientation modulation. In the print end, dots of two colorants occupy the same spatial region. At the detector end, by using the complementary sensor channels to estimate the colorant channels, data is recovered in each colorant channel. The method approximately doubles the capacity of encoding methods based upon a single colorant channel and enables embedding rates which match or exceed that of other hardcopy barcodes known in the arts. The method is robust against inter-separation misregistration with a small symbol error rate.