Abstract: Undesirable artifacts appearing in color images, such as blooming or smudging around the edges of text, are avoided through selective reduction of the color gamut for objects which form the image. Individual component color values are modified by taking into account combinations of colors and their effect upon the artifacts to be eliminated. Only those parameter values which contribute to the artifact are modified. Other parameter values are left intact, to maintain the original image characteristics. When a color value is modified, all components of that color are modified in a symmetrical manner, to preserve the hue of the original color. The impact on the image is further minimized by selectively applying color correction only to those objects in which the artifact is pronounced.

Abstract: An improved covariance matrix encoding scheme wherein a covariance matrix is described in terms of Euler angles and eigenvalues. A covariance matrix, P, is decomposed into its eigenvalues and eigenvectors. The eigenvalues and their corresponding eigenvectors are arranged starting with the smallest value, and the next two ordered such that, the eigenvector set comprises a right-handed coordinate system. Each eigenvalue is then encoded with a logarithmic or other compression scheme. Euler angles are calculated and angle is compressed and an offset is added to each angle. The covariance matrix is then reconstructed from the encoded values to test if the encoded matrix completely covers the original matrix. If necessary, a scale factor is applied to all reconstructed eigenvalues and the scaled versions are then re-encoded as described above. The scaling and re-encoding process ensures that the encoded matrix covers the original matrix.

Abstract: A method, system and computer software product for improving rate-distortion performance while remaining faithful to JPEG/MPEG syntax, involving joint optimization of Huffman tables, quantization step sizes and quantized coefficients of a JPEG/MPEG encoder. This involves finding the optimal coefficient indices in the form of (run, size) pairs. By employing an interactive process including this search for optimal coefficient indices, joint improvement of run-length coding, Huffman coding and quantization table selection may be achieved. Additionally, the compression of quantized DC coefficients may also be improved using a trellis-structure.

Abstract: Methods are described for efficient reconstruction of MRI data. In one practice, new reconstruction algorithms for non-uniformly sampled k-space data are presented. In the disclosed algorithms, Iterative Next-Neighbor re-Gridding (INNG) and Block INNG (BINNG), iterative procedures are performed using larger rescaled matrices than the target grid matrix In BINNG algorithm, the sampled k-space region is partitioned into several blocks and the INNG algorithm is applied to each block. In another practice, a novel partial spiral reconstruction (PFSR) uses an estimated phase map from a low-resolution image reconstructed from the central k-space data and performs iterations, similar to the iterative procedures with INNG, with an imposed phase constraint. According to yet another practice, an off-resonance correction is performed on matrices that are smaller than the full image matrix. All these methods reduce the computational costs while rendering high-quality reconstructed images.

Abstract: A graphic image that has pixels arranged in rows and columns is scaled by processing a succession of segments. Each segment comprises contiguous pixels. The row and column dimensions of each segment do not correspond to an intended degree of scaling in both dimensions. The processing of each segment produces an intermediate pixel. The intermediate pixels form a stream. The intermediate stream of pixels is processed to form a final two-dimensional scaled image.

Abstract: Systems and methods are presented for image comparison by metric embeddings. In one implementation, a graph is created from each image to be compared. Graph metrics are then embedded in families of trees for each image. Minimum differences between the respective families of trees for different images are compiled into a matrix, from which a similarity measure is obtained for image comparison.

Abstract: A print medium quality adjustment system includes an inspection watermark medium output device 11 having an inspection watermark signal generation unit 101 that generates at least one inspection watermark signal, generates a watermark signal image by disposing the inspection watermark signal(s) in an arbitrary arrangement, and generates inspection training data 105 having digitally recorded therein the inspection watermark signal(s). An inspection medium output unit 103 prints the inspection watermark image onto a medium. A watermark quality inspection device 12 has an output unit 106 that scans the printed medium, a signal detection unit 107 that extracts embedded watermark information, and a print quality judgment unit 108 that judges the watermark quality by comparing the extracted watermark information with the inspection training data. Based upon the quality judgment results, a print adjustment value 110 is generated to be used to improve the print quality.

Abstract: The invention provides an image processing apparatus and an image processing method. An area to which image data belongs is discriminated, and a correction coefficient to be used for correction of a pixel value of the image data is produced based on a result of the discrimination. Then, the pixel value of the image data is corrected with the correction coefficient. The relationship in magnitude among pixel values in the same area is maintained because the same coefficient is used, but pixel values which belong to different areas can be varied or even reversed. This allows the gradation of an entire image to be corrected while preventing partial deterioration of the contrast.

Abstract: A method and system are described for compensating for the phase error in PCMR images due to eddy current effects. The phase noise due to eddy currents may be measured and characterized from phase images at selected regions near a vessel of interest.

Abstract: A binary coding method of a fingerprint image, the method comprises detecting a ridge range direction and a ridge curvature of the fingerprint image; and binary coding the fingerprint image using a binary coding filter selected in accordance with the ridge curvature.

Abstract: Described is a method and system for authenticating identity of a person using a portable device. The portable device may includes an imager, an image processing unit and a processor. The image processing unit reads encoded data in a first image from an imager of the device. The image processing unit extracts a portion of a second image from the imager to generate extracted portion data. The extracted portion of the second image corresponds to a portion of a person whose identity is to be authenticated. Stored biometric data for a person is located based on the data read from the first image. The processor compares the extracted portion data of the second image to the stored biometric data for a person.

Abstract: Color management which converts internal color appearance space color values to CMYK device values. CMY values are interpolated from a plurality of CMY to color appearance space lookup tables, wherein each CMY table is associated with a specific value of K. A target internal color value is received and one of the plurality of CMY lookup tables is selected based on a lightness value and neutrality of the target internal color value. A CMY value is interpolated from the selected lookup table and the target internal color value. The interpolated CMY value together with the associated K value from the selected table is provided as the converted CMYK color value. Advantageously, the conversion effects control over the output K value in a color appearance space to CMYK conversion. Accordingly, both neutral and non-neutral colors can be reproduced with better accuracy and higher quality.

Abstract: A method, apparatus, and a computer readable hardware storage medium with instructions to encode a series of quantized transform coefficients. The method includes identifying runs of one or more non-zero coefficients, and for each such run, identifying events of consecutive amplitude-1 coefficients followed by a single amplitude>1 coefficient. The method further includes encoding the identified event with a codeword, each event identified according to the length of the consecutive amplitude-1 coefficients and the amplitude of the ending coefficient. The method is such that relatively short codewords are formed to represent values or sequences of values that are relatively more likely-to-occur, and relatively long codewords are formed to represent values or sequences of values that are relatively less likely-to-occur. The method is applicable to encoding a region in the series where there is likely to be a cluster of non-zero-valued coefficients.

Abstract: A method, apparatus, and carrier medium to encode a series of quantized transform coefficients. The method includes identifying clusters of at least one non-zero-valued coefficients, and for each such cluster, identifying at least one position event that defines the relative position and runlength of the cluster of non-zero coefficients and any intervening run of zero-valued coefficients, and identifying at least one amplitude event to define the amplitudes of the non-zero-valued coefficients in the identified cluster. The method further includes jointly encoding the identified position event or events with the identified amplitude event or events such that relatively short codewords are formed to represent values or sequences of values that are relatively more likely-to-occur, and relatively long codewords are formed to represent values or sequences of values that are relatively less likely-to-occur.

Abstract: A method, apparatus, and computer readable medium to encode a series of quantized transform coefficients. The method includes identifying events that each includes a run of one or more non-zero-valued coefficients, and for each such event, encoding the event with a codeword that for at least some events, relatively more likely-to-occur events are encoded by a shorter codeword than relatively less likely-to-occur events, and for each identified event, jointly encoding according to an amplitude coding method, a plurality of consecutive values in the run of consecutive non-zero-valued coefficients. The method is applicable to encoding a region in the series where there is likely to be a cluster of non-zero-valued coefficient.

Abstract: An open set recognition system utilizing transductive inference including capture device(s), a basis, quality checker(s), feature extractor(s), a gallery, a rejection threshold, a storage mechanism, and a recognition stage. The basis encodes sample(s) and is derived using training samples. The feature extractor(s) generates signature(s) from sample(s) using the basis. The rejection threshold is created using a rejection threshold learning mechanism that calculates the rejection threshold using sample(s) by: swapping a sample identifier with other sample identifier(s); computing a credibility value for the swapped sample identifiers; deriving a peak-to-side ratio distribution using the credibility values; and determining the rejection threshold using the peak-to-side ratio distribution. The open set recognition stage authenticates or reject as unknown the identity of unknown sample(s) using derived credibility values, derived peak-to-side ratios for the unknown sample and the rejection threshold.

Abstract: The present invention relates to a color management method for controlling the amount of black ink used by a destination device with a black channel when converting colors from one of a plurality of source device color spaces to destination device color space. This conversion is accomplished by obtaining a black weight of a source pixel in the source device color space, transforming the source pixel into a color in color appearance space, and calculating destination values based on the color in color appearance space and the obtained black weight. In the case that the source device color space does not include a black channel, the black weight is obtained from a color purity of the source pixel. In the case that the source device color space is a device space including a K channel, the black weight is obtained from the K channel.

Abstract: A method and an apparatus of image compression, and a memory to store a data structure for compression. The method includes, for an ordered series of quantized coefficients of a transform of an image block, forming from the series events that are a run of non-zero-valued coefficients in a first contiguous region defined by a breakpoint, a run of zero-valued coefficients in the first region, or a run of zero-valued coefficients that ends in a non-zero-amplitude coefficient in a second region defined by the breakpoint. A codeword is formed for each runlength of non-zero-valued and zero-valued coefficients in the first region using a first and a second coding method, respectively, and, and encoding the runs of zero-valued coefficient that end in a non-zero value in the second region according to a third coding method, including providing an exception codeword when the ending amplitude is not 1.

Abstract: A method and apparatus for performing progressive order conversion is described. In one embodiment, a system comprises a memory and a progressive order conversion parser. The memory stores a compressed image as a codestream in a first progression order and the progression order conversion parser converts the codestream from the first progression order to a second progression order different than the first progression order.

Abstract: A method for content-aware image retargeting generates an energy image from a source image according to an energy function. From the energy image, one or more seams are determined according to a minimizing function such that each seam has a minimal energy. Each seam is applied to the source image to obtain a target image that preserves content and a rectangular shape of the source image.