Abstract: A system and method for performing threshold stamping are disclosed. First and second threshold values corresponding to first and second pixels may be retrieved from a threshold memory. A plurality of upscaled threshold values may optionally be computed based on the first threshold value and the second threshold value. An (upscaled) threshold value may be updated at each of one or more first register blocks. A binary pixel value may be computed based at least in part on the first updated threshold value. The first updated threshold value may be updated at each of one or more second register blocks. A downscaled threshold value may optionally be computed based on a plurality of second updated threshold values. The downscaled threshold value or second updated threshold value may be damped in a damping circuit, and the damped threshold value may be stored in the threshold memory.

Abstract: The image processing method for obtaining a quantized image from a multiple tone image, the method comprises: an image dividing step of dividing an input image into a plurality of image blocks of a unit block size; a threshold value matrix specification step of specifying threshold value matrices for the input image with respect to each of the image blocks from a plurality of threshold value matrices including a first threshold value matrix having the unit block size and a second threshold value matrix dividable into a plurality of sub-matrices each having the unit block size; and a threshold value matrix setting step of setting threshold value matrices in image blocks for which the second threshold value matrix has been specified as the threshold value matrix, in such a manner that adjacent positional relationships between sub-matrices formed when the second threshold value matrix is divided into sub-matrix units are preserved.

Abstract: An image processing device includes a memory that is adapted to store an input image; an inverted image generator that is adapted to generate an inverted image, the inverted image corresponding to a predetermined part of the input image; a target image generator that is adapted to generate a target image, the target image including the inverted image and the input image; a quantization unit that is adapted to quantize the target image, in accordance with the error diffusion method; an image extractor that is adapted to extract an output image from the quantized target image, the output image corresponding to the input image; an output unit that is adapted to output the output image extracted by the image extractor.

Abstract: An image encoding apparatus includes a quantization control section that supplies a rounded Q-scale to a quantization section for quantizing each macroblock according to the rounded Q-scale. A Q-scale is generated for each macroblock based on the amount of generated codes produced by encoding. The Q-scale is rounded within a set range by a rounding control section. The rounded Q-scale is smaller in amount than the Q-scale. Since the same Q-scale values will continue in succession, these can be omitted from a stream, allowing the reduced amount of quantization information and the increased amount of information allocated to images.

Abstract: In an image forming system, an information processing apparatus (host computer) outputs print data to a printer connected to the apparatus through an interface. The apparatus includes an interface identifying module for identifying the type of the interface, a query module for determining, based on the identified interface type, a quantization method for quantizing print data and/or a compression method, and an image processing module for performing quantization and/or compression on the print data by the determined quantization method and/or compression method. The apparatus outputs, to the printer, the print data processed by the image processing module.

Abstract: Error diffusion is performed using a Floyd-Steinberg-like approach. A integer-representation of a running error is compressed by storing only its most significant bits and returning any remainder to the error diffusion processor. The running error is shifted to the right until only the desired number of significant bits remain, and this compressed error is stored. Any portion of the original running error that is lost due to the shifting is treated as a remainder and is returned to the error diffusion processor for use in calculating an adjusted current pixel value. The amount of the shift is retained in compressed form to keep track of the number of shifts needed to form a truncated running error from the compressed running error.

Abstract: A device including: an acquirer acquiring image data having an M-value (M?3) pixel value; a memory storing nozzle information; another memory storing error diffusion matrices having different diffusion ratios of an error; a selector selecting specific pixel data in the image data; an N-value converter converting the M-value to an N value (M>N?2); a diffuser diffusing the error to pixel data not subjected to the conversion in the image data according to the error diffusion matrix by using a difference between a selected pixel data value before and after conversion as the error; a generator generating print data defining nozzle dot information corresponding to the image data after the conversion; and a printer. The diffuser selects a specific error diffusion matrix for each selected pixel data according to the nozzle information, and diffuses the error to the pixel data not subjected to the conversion.

Abstract: A method for multi-toning an input digital image having input pixels with two or more color channels to form an output digital image having modified output levels. The method includes producing shifted error signals for each color channel, weighting the shifted error signals to determine weighted error signals for nearby pixels that have yet to be processed; producing shifted weighted error signals; and adjusting the input levels for the nearby pixels responsive to the shifted weighted error signals.

Abstract: An image processing method and apparatus is provided that executes conversion processing of image data according to an error diffusion method. A unit processing for one pixel of the original image and another unit processing for an interpolate pixel that is inserted between lines of pixels of the original image are executed in the line direction. The processings for one line are sequentially repeated for each line of the original image. A calculating portion, for calculating an average error value which is an average of error values of a plurality of neighboring pixels, is utilized for converting a pixel value of a target pixel. A plurality of multiplying sections and addition memory sections are provided in correspondence with the alignment of a plurality of previous-line-neighboring pixels in a previous line located ahead of a pixel line in which the target pixel exists.

Abstract: Methods and systems for performing threshold stamping are disclosed. A pixel intensity value for a first pixel may be determined. A pixel value for the first pixel may be retrieved from a memory location corresponding to the first pixel. A threshold delta value may then be determined based on the pixel value and added to a base threshold value to produce a threshold value. If the pixel intensity value exceeds the threshold value, a plurality of pixel values corresponding to a plurality of pixels may be updated. The plurality of pixels may include the first pixel and one or more second pixels. Otherwise, the pixel value for the first pixel may be updated.

Abstract: An image forming device includes a quantization unit which quantizes each pixel of an M-level gradation input image into one of N levels (M>N?2) through an error diffusion process. An operation unit performs a predetermined operation according to a position of a target pixel to a gradation value of the target pixel before quantization when the gradation value of the target pixel is equal to a specific concentration.

Abstract: A method for setting a boundary value at a level of error diffusion, comprising a step of defining a characteristic curve on a coordinate plane defined by a first axis indicating a perceptually uniform scale and a second axis indicating grayscale values of original data. The perceptually uniform scale is given by a normalized one of chromatic tristimulus values to the power of ?. A boundary value at a level of error diffusion is determined based on the characteristic curve and is stored in a storage device. The boundary value is read from the storage device for error diffusion processing, and error diffusion is performed on input image data using the read boundary value.

Abstract: Error diffusion is performed upon input image data. In one aspect, multiple error diffusion processing elements perform error diffusion on a selected pixel in parallel. In another aspect, the error diffusion logic is integrally formed with a fast local memory in the same electronic device, such as an ASIC. The error data produced by the error diffusion logic for a pixel is buffered in the fast local memory until it is to be used by the error diffusion logic on other pixels. In still another aspect, a first-in-first-out (FIFO) buffer regulates or buffers the color image data between the output of a color conversion system, such as a colorant lookup table, and the input an error diffusion processing element. In yet another aspect, the error diffusion logic has tagging logic that produces and stores an indicator, either in the output data stream itself or in a separate area, to indicate whether a raster contains printable data.

Abstract: A digital image coding device based on wavelet transform technology includes a lower-bitplane replacement section which is provided after a coefficient modeling section and before an arithmetic coding section. The coefficient modeling section converts wavelet coefficients into binary data composed of a plurality of bitplanes for each code-block. The lower-bitplane replacement section replaces a designated number of lower-order bitplanes of the plurality of bitplanes with zero to produce modified binary data. The designated number of low-order bitplanes is designated depending on a noise characteristic of the image capturing device. The arithmetic coding section codes bitplanes of the modified binary data.

Abstract: Image processing apparatus and image processing method for formation of high quality image by high-speed error diffusion processing by execution of more complicated threshold condition processing in a simple manner. When error diffusion processing is performed on multivalued image data having plural density components and the result of processing is outputted, upon execution of error diffusion processing on a first density component among the plural density components, a threshold value used in the error diffusion processing is determined based on a density value of a second density component, then the error diffusion processing is performed on the first density component based on the determined threshold value, and the result of execution of the error diffusion processing is outputted.

Abstract: A method for enhancing the print quality of halftone images makes use of error diffusion to perform halftone image processing to a document. After an RGB image is obtained by scanning the document, a high-pass filter is used to detect the edge characteristics and edge directions of the RGB image. Next, during the error diffusion process, a condition quantizer is used to separately process pixels both with and without edge characteristics based on the edge characteristics, gray scale values, and accumulated errors of input pixels. Pixels without edge characteristics can thus have a smoother distribution by means of error diffusion, and the pixels with edge characteristics can have a concentrated distribution, thereby the edge of the text in the document can be sharpened.

Abstract: Techniques and mechanisms for performing error minimizing requantization are provided. Quantized coefficients associated with a bitstream are received. It is determined whether the quantized coefficients are associated with an inter macroblock or an intra macroblock. Inter macroblock and intra macroblock formulas minimizing requantization error are applied to determine requantized coefficients.

Abstract: Methods, apparatus and computer readable medium are described that compress and/or decompress digital images in a lossless or a lossy manner. In some embodiments, a display controller may quantize pels of a digital image and may identify runs of successive quantized pels which are equal. The display controller may generate a symbol to represent an identified run of pels. The symbol may comprise a run length and a quantized pel that may be used to reconstruct the run of pels. The symbol may further comprise an error vector for each of the pels of the run that may be used to further reconstruct the run of pels.

Abstract: A method and system are presented for enhancing one or more images of an object, so as to increase the visibility within the images of one or more structures within the object. The object may be an anatomical region of a patient, and may include one or more reference structures, for example skeletal structures or vertebral structures, and one or more treatment targets, for example tumors or lesions. An operator, for example a top-hat filter operator, selects at least a first neighborhood and a second neighborhood within the images. The operator selects within each neighborhood one or more pixels having an optimal pixel value, and eliminates the remaining pixels in these neighborhoods. When the operator is applied to the selected neighborhoods, only the pixels having the greatest pixel values remain in the selected neighborhoods, and the remaining pixels are eliminated in the selected neighborhoods. As a result, desired features can be located and enhanced in the images.

Abstract: An apparatus includes a control module and an activity module. The control module provides error control information based on a target number of bits and an actual number of bits required to pack at least one compressed block of image information. The activity module provides a quantization factor based on the error control information and a complexity value of the at least one compressed block of image information. The quantization factor is used to pack the at least one compressed block of image information into a bitstream comprising the target number of bits.

Abstract: An error adding step adds together input multi-tone image data and peripheral error information. An adding/subtracting step adds to or subtracts from multi-tone image data calculated by the error adding step, a random number in a matrix prepared for each set of pixels of the input multi-tone image data. A quantizing step quantizes multi-tone image data calculated by the adding/subtracting step into image data, the number of bits of which image data being smaller than the number of bits of the multi-tone image data calculated by the adding/subtracting step. An error calculating step calculates an error based on the multi-tone image data calculated by the error adding step and the image data quantized by the quantizing step. An error storing step stores the error calculated by the error calculating step for each peripheral pixel.

Abstract: Quantization for oversampled signals with an error minimization searches based upon clusters of possible sampling vectors where the clusters have minimal correlation and thereby decrease reconstruction error as a function of oversampling (redundancy) ratio.

Abstract: Error diffusion is performed using a Floyd-Steinberg-like approach. A integer-representation of a running error is compressed by storing only its most significant bits and returning any remainder to the error diffusion processor. The running error is shifted to the right until only the desired number of significant bits remain, and this compressed error is stored. Any portion of the original running error that is lost due to the shifting is treated as a remainder and is returned to the error diffusion processor for use in calculating an adjusted current pixel value. The amount of the shift is retained in compressed form to keep track of the number of shifts needed to form a truncated running error from the compressed running error.

Abstract: A halftone reproduction processing section (29) of an image processing apparatus (13) has a control part that conducts a halftone processing of input image data by subjecting it to an error diffusion processing, selects input image data on at most one, namely, one or no input image data from the input image data on at least seven colors, namely, primary colors of cyan, magenta, and yellow used as visible colors for forming an image on a recording medium, secondary colors of red, green, and blue that are the complementary colors of the visible colors, and black, and subjects the input image data on the other colors to a different error diffusion processing.

Abstract: In one embodiment, the present invention is implemented as a GPU configured for traversing pixels of an area. The GPU includes a set-up unit for generating polygon descriptions and a rasterizer unit coupled to the set-up unit for rasterizing the polygon descriptions. The rasterizer unit is configured to traverse a plurality of pixels of an image using a first boustrophedonic pattern along a predominant axis, and during the traversal using the first boustrophedonic pattern, traverse a plurality of pixels of the image using a second boustrophedonic pattern, wherein the second boustrophedonic pattern is nested within the first boustrophedonic pattern.

Abstract: A method and system for performing error diffusion are disclosed. An ordered set of pixels, including a pixel intensity value for each pixel, is received. Each pixel intensity value includes a value within a range from a low value to a high value, inclusive. An initial error value is also received. Based on the pixel intensity values and the initial error value, a pixel value for each pixel and an updated error value are computed substantially simultaneously with each other.

Abstract: An image processor has: a unit that executes a conversion process on input image data represented by pixels of M grayscales (M?3), to convert the input data into output image data represented by sub-pixels of two grayscales; and a unit that outputs the output data, wherein the conversion process includes: a process to determine a filling pattern of sub-pixels corresponding to a pixel of interest of the input data according to a corrected grayscale value obtained by adding a correction value to a grayscale value of the pixel of interest; and the pattern includes a core pattern which forms a core of a dot and a growth pattern which grows a dot, the correction value includes a diffused error, and at least a part of the diffused error obtained by weighting an error of a pixel determined as the core pattern is not included in the correction value.

Abstract: An image processing device includes a pre-processing unit, an adder, a quantization unit, a post-processing unit and a surrounding error calculating unit. The pre-processing unit calculates an average pixel value of an aggregated pixel formed of a plurality of adjacent pixels for input image data. The adder calculates a correction average pixel value by adding a correction error value to an average pixel value of a target aggregated pixel to be a processing object. The quantization unit carries out a quantization processing of the correction average pixel value at a quantization level of a prescribed number. The post-processing unit divides the aggregated pixel into a plurality of pixels and allocates a pixel value corresponding to the quantization level to each of the divided pixels. The surrounding error calculating unit calculates a correction error value for processing a surrounding target aggregated pixel in accordance with a quantization error generated in the quantization processing.

Abstract: When the input value becomes close to the medium dot relative density value (Den_M), the large dot threshold value (Thre_L) and medium dot threshold value (Thre_M) become close to each other. It is possible to prevent output values from being converged to the particular medium-dot output value. When the input value becomes close to the small dot relative density value (Den_S), the medium dot threshold value (Thre_M) and the small dot relative density value (Den_S) become close to each other. It is possible to prevent output values from being converged to the particular small-dot output value.

Abstract: A system and method for performing threshold stamping are disclosed. First and second threshold values corresponding to first and second pixels may be retrieved from a threshold memory. A plurality of upscaled threshold values may optionally be computed based on the first threshold value and the second threshold value. An (upscaled) threshold value may be updated at each of one or more first register blocks. A binary pixel value may be computed based at least in part on the first updated threshold value. The first updated threshold value may be updated at each of one or more second register blocks. A downscaled threshold value may optionally be computed based on a plurality of second updated threshold values. The downscaled threshold value or second updated threshold value may be damped in a damping circuit, and the damped threshold value may be stored in the threshold memory.

Abstract: A technique for the modification of sub-pixels to hide defects for defective sub-pixels.

Abstract: An improved digital halftoning method that uses an input image's global gray levels to determine the local gray levels of a monochrome output image. Input multi-bit pixels grouped into two-pixel-by-two-pixel local subcells are variously aggregated into one or more larger supercells. The size of said supercell(s) is related to and limited by the size of the global input bitmap. A final monochrome gray level is derived from said supercell(s) and distributed within contained subcells. Subcell gray levels are expressed as interim whole monochrome pixels and gray level remainders. A comparison is made of the final supercell and the summed interim subcell monochrome gray levels. An ordering of the remainders is used for assignment of additional monochrome pixels, if necessary, to yield final subcell monochrome gray levels. Gray level rounding errors thus are quantized by reverse diffusion until a monochrome gray level for each of the global image's two-pixel-by-two-pixel local subcells is derived.

Abstract: An error utilization factor line, indicative of a relationship between the amount of the error utilization factor K and input data for a present pixel, is determined dependently on characteristics of the image, on the value of the threshold, on the size of the distribution matrix, or on the condition of the recording operation. The amount of the error utilization factor K is determined dependently on the input data of the present pixel and based on the error utilization factor line. The correction amount F, collected from the already-processed nearby pixel, is multiplied by the error utilization factor K, before being added to the input data of the present pixel for the halftone process.

Abstract: This is an image processing device for predicting the lower-order bits of target pixel data, based on one or more pieces of pixel data constituting image data. The image processing device comprises a lower-order bit calculation unit for calculating the lower-order bits of the target pixel data, based on one or more pieces of pixel data constituting image data and specifying the data as corrected lower-order bits and a lower-order bit superimposition unit for superimposing the corrected lower-order bits calculated by the lower-order bit calculation unit on higher-order bits of the target pixel data.

Abstract: A method of adjusting a TRC of an image is provided. The method involves receiving an image at an input resolution, resampling the image to a processing resolution if the imput resolution and the processing resolution are not same, processing the image using rank-ordered error diffusion, and resampling the processed image to a desired output resolution for the image if the processing resolution and the output resolution are not same.

Abstract: A technique to perform error distribution in a graphics system. More particularly, embodiments of the invention include at least one technique to distribute the error resulting from converting computer generated graphics pixels from one pixel depth to another.

Abstract: A data compression system and method provides a best base searching method to determine the best orthogonal basis function for wavelet-based, data compression. A processing device may receive data signals from a source and wavelet-based data compression may be performed on the received data before transmission (to a receiving component) and/or further digital signal processing (DSP) of the data signals. An encoder portion of the processing device performs the data compression using a predetermined algorithm that determines the best orthogonal basis function (base) of the signal transform (used for representing the data signals) by searching a set of bases including (approximately) all orthogonal bases available to provide the minimum number of coefficients for efficient data compression while maintaining a low error rate in reconstructing the original data signals.

Abstract: In various embodiments of the present invention, a noisy signal denoiser is tuned and optimized by selecting denoiser parameters that provide relatively highly compressible denoiser output. When the original signal can be compared to the output of a denoiser, the denoiser can be accurately tuned and adjusted in order to produce a denoised signal that resembles as closely as possible the clear signal originally transmitted through a noise-introducing channel. However, when the clear signal is not available, as in many communications applications, other methods are needed. By adjusting the parameters to provide a denoised signal that is globally or locally maximally compressible, the denoiser can be optimized despite inaccessibility of the original, clear signal.

Abstract: An ink saving and tone correction printing technique using error diffusion (EDF) includes receiving a first pixel value vi,j and comparing the first pixel value vi,j with a threshold value to produce a second pixel value bi,j and a reference value pi,j. When the first pixel value vi,j is less than a threshold value, not outputting the second pixel value bi,j and the reference value pi,j is the area of actual non-blank region within a pixel region. When the first pixel value vi,j is greater than the threshold value, outputting the second pixel value bi,j for printing on the pixel region, and the reference value pi,j is the area of actually increased non-blank region within the pixel region and the adjacent pixel regions in which a processing prior to printing has been conducted to decide whether or not to print.

Abstract: In various embodiments of the present invention, a context-based denoiser is applied to each noisy-image symbol embedded within a context to determine a replacement symbol for the noisy-signal symbol. The context-based denoiser includes a context-modeling component that efficiently generates context classes and symbol-prediction classes, assigns individual contexts to context classes and symbol-prediction classes, collects symbol-occurrence statistics related to the generated context classes and symbol-prediction classes, and, optionally, generates noisy-symbol predictions.

Abstract: A printing apparatus includes: a unit that generates test pattern data considering visual characteristics, on the basis of a test pattern grayscale value determined on the basis of visual sensitivity; an N-value conversion unit that converts the test pattern data generated by the unit that generates test pattern data considering visual characteristics into an N value (N?2: N is a natural number); a printing data generating unit that generates test pattern printing data on the basis of the N-value test pattern data output from the N-value conversion unit; a printing unit that performs printing on the basis of the test pattern printing data generated by the printing data generating unit; an output density detecting unit that detects the output density of a test pattern printed by the printing unit; a printer input/output density information generating unit that generates printer input/output density information for correcting input density, on the basis of the output density of the test pattern detected by the

Abstract: A method and system for rotation-dependent halftone rendering. An image input is received from a scanning system or other source, the received image being either a contone image or an error-diffused mage. If a following right-angle image rotation is to be performed, the image is clustered by a clustering method which yields reduced file sizes with respect to the rotated orientation of the image. If no following right-angle image rotation will be performed, the binary image is clustered by an alternate clustering method which yields reduced file sizes with respect to the non-rotated image. The selective clustering includes dividing the image into a tessellation of cells and then concatenating like bits in each cell in a preferred direction for the rotated or non-rotated image. The clustered image is then rotated if necessary, and compressed.

Abstract: A device and method is provided for breaking up undesirable patterns in vector error diffusion when the sum of inputs is near fraction values of the total input range. In the method, the value of the sum is calculated modulo the maximum input value. The mod value tendency to produce limit cycles is then determined for multiple planes in a manner similar to that for an individual plane. The threshold process for the vector calculation can then be modified to break up the cycles that occur in the combinations of the multiple colors. Typically, the largest of the individual plane modifications and the vector sum mod value is used for threshold modification. At least two different types of threshold modifications are possible: (1) random or psuedo-random noise address to the threshold; and (2) non-contiguous regions of threshold.

Abstract: A method for processing image data that employs a stamp field that contains data representing a distance metric for use with a variety of error diffusion operations. The distance metric possesses distance-order preservation permitting the distance from a previous dot to be determined by incrementing the distance metric, without knowing precisely where the previous dot was printed.

Abstract: A system and method for processing a gray level in a display device performs a random error diffusion operation on the video data using a first random coefficient value and a random dithering operation on the error-diffused video data using a second random coefficient value.

Abstract: A vector error diffusion (VED) method employable in cycles with respect to a hi-tonal color printing engine which prints bi-tonal color images in a device output color space. The method generally includes (a) acquiring input color-image data which is characterized with an input color space, (b) processing, with available pre-established VED accumulated error data, such input data to produce a VED-processed input color-image data stream, (c) from such VED-processed input color-image data stream, creating, without employing interpolation, a VED-processed output color-image data stream which is characterized by the mentioned device output color space, and which is suitable for delivery to and use by the mentioned printing engine, and (d) changing, as appropriate for the next cycle, the VED accumulated error data which will be employed in that next cycle as pre-established VED accumulated error data.

Abstract: Even when a color difference diffusion (CD) method which allows high-speed color separation is used, it is difficult to attain preferred color reproduction corresponding to various user's requirements using a small-scale circuit. Hence, a color converter color-converts input image data using a 3D table selected from a plurality of 3D tables, and an interpolation process. A quantization processor obtains error-corrected data by adding error data to the color-converted image data. A dot pattern is selected based on the error-corrected data. The selected dot pattern is output to a print section. The error data is obtained by calculating the difference between a predetermined value corresponding to the dot pattern, and the error-corrected data. The error data is diffused to surrounding pixels.

Abstract: A method for multi-level halftoning an input digital image to form an output digital image which includes a multi-level error diffusion halftoning process incorporating periodic dither signals whose amplitudes are adjusted as a function of the error-diffusion texture characteristics.

Abstract: An image processing device performs an error diffusion on multilevel input image data to generate multilevel output image data that has fewer levels than the multilevel input image data. The image processing device includes a plurality of setting devices, each of which sets a threshold value to be used at the error diffusion, a threshold value selecting device that randomly selects one of the plurality of setting devices with respect to each pixel to be processed and allows the selected setting device to set a threshold value with respect to the pixel to be processed when the image processing device performs the error diffusion, and a converting device that converts the pixel to be processed into multilevel output image data with fewer levels than multilevel input image data by the error diffusion, in accordance with the threshold value set by the setting device selected by the threshold value selecting device.

Abstract: A method for multi-toning an input digital image having input pixels with two or more color channels to form an output digital image having modified output levels. The method includes producing an error signal for each color channel, combining the error signals to produce a combined error signal, sorting the error signals to produce a set of sorted error signals, and determining modified output levels responsive to the set of sorted error signals and the combined error signal.