Abstract: A minimum area rectangle inscription method and system for automatically generating a minimum area rectangle that inscribes and bounds an approximately rectangular object (or “noisy” object) contained within scanned image data. The minimum area rectangle inscription method chooses an interior point located inside the object boundary and determine perimeter points located on the boundary. A convex hull is constructed from at least some of the perimeter points such that each side of the convex hull is convex. Inscribing rectangles, equal in number to the sides of the convex hull, are constructed such that each inscribing rectangle shares a side with the convex hull and circumscribes approximately the entire convex hull. The area of each of the inscribing rectangles is calculated, and the inscribing rectangle having the least amount of area is designated as the minimum area rectangle.

Abstract: An image processing system provides image enhancement and anti-clipping units. The anti-clipping unit for image sharpness enhancement, operates such that any shoot artifacts in the enhanced image that go beyond pixel value lower/upper bounds are properly adjusted back within the lower and upper bounds, without causing prominent edge jaggedness artifacts in the final resulting output image.

Abstract: A method of rendering text in an image forming device comprises providing a user interface to receive a user-defined font sharpening threshold; receiving the user-defined font sharpening threshold entered by user via the user interface, selecting a halftone screen for text based on text size and a user defined font sharpening threshold; and rendering the text with the selected halftone screen.

Abstract: A plurality of relative orientation detection filters having orientation coefficients that represent a relative orientation of a connected sequence of pixel drawing regions with their pixel values distributed in a predetermined pattern in a buffer memory having the same structure as an image memory, and a plurality of smoothing filters having smoothing coefficients for corresponding relative orientations, are prepared. A rendering unit draws an image to the buffer memory. A relative orientation of an edge in this image is detected by means of selecting out one relative orientation detection filter that is most suitable for the relative orientation in question. Pixel values for the edge are smoothed by using the smoothing filter according to the detected relative orientation. Then, drawing data including the smoothed pixel values are written into the image memory.

Abstract: A video image processing system is described that generates the interpolated video images with sharp and jaggedness-free edges. A method of video image processing is also described that interpolates video images to generate the video images with sharp and jaggedness-free edges. The video image processing system receives and makes input image data available for further processing; analyzes the local features of the input image data; filters the input image data before performing interpolation process; modifies the phase value adaptive to the local edge distance; rescales the input image data in horizontal interpolation using the modified phase value; and rescales the horizontally interpolated image data in vertical interpolation using modified phase value.

Abstract: A method, system, and computer-readable storage medium are disclosed for performing anti-aliasing operations on lines using a graphics processing unit (GPU). Input comprising a plurality of vertices may be received at a GPU. The plurality of vertices may represent one or more line segments. One or more anti-aliased line segments may be generated based on the input. In generating the one or more anti-aliased line segments, the intensity of a first edge and a second edge of each line segment may be modified based on application of an anti-aliasing function. A maximum intensity of a central portion may be maintained for at least one of the line segments, wherein the central portion is between the two edges and is greater than one pixel in thickness.

Abstract: Embodiments of a filtering method and apparatus for anti-aliasing as described herein take advantage of improved existing hardware by using as input the data stored in the multisampling anti-aliasing (MSAA) buffers after rendering. The standard hardware box-filter is then replaced with a more intelligent resolve implemented using shader programs. Embodiments find scene edges using existing samples generated by Graphics Processing Unit (GPU) hardware. Using samples from a footprint larger than a single pixel, a gradient is calculated matching the direction of an edge. A non-linear filter over contributing samples in the direction of the gradient gives the final result.

Abstract: A blur checking region is determined by selecting a region in which a blur tends to clearly appear in a digital photograph image as the blur checking region. Then, an image of a region corresponding to the blur checking region is obtained as a checking image in a corrected image obtained by performing blur correction processing on the digital photograph image. Then, the obtained checking image is displayed in a size appropriate for the resolution of a display device.

Abstract: An image capture device includes a processor configured to generate pseudo-random numbers. Optionally, these pseudo-random numbers may use a portion of an image as a seed for the random number generator. These random numbers are used in the post-processing of digital images to create a variety pseudo-random image effects such as; unique frame colors, line thicknesses, line and/or shape placements, image copies, filter strengths, shape choices and color blends. These effects are applied to a selected digital image creating a unique final image.

Abstract: Noises are reduced in an image picked up in natural light without using lighting equipment that affect the picked up image. The present invention provides an image processing apparatus that includes an image acquisition unit that acquires a visible light image and an invisible light image corresponding to the visible light image, and a noise reduction unit that reduces noises of the visible light image by using the invisible light image.

Abstract: Systems and methods for scan converting data into compressed representations of pixel data are described. In one aspect, shape geometry including shape and/or position attributes of one or more objects are directly scan converted into compressed scan converted data. The compressed scan converted data is stored into memory for subsequent application access and rendering.

Abstract: A method for compressing two color anti-aliased images takes advantage of the fact that when two color anti-aliased images are present, it is often the case that the two base colors appear in adjacent or continuous series or “runs” of pixels representing the same color. According to one embodiment to the present invention, these runs are identified and then the color and run length are encoded to produce increased compression efficiency.

Abstract: A graphics system has a mode of operation in which real samples and virtual samples are generated for anti-aliasing pixels. Each virtual sample identifies a set of real samples associated with a common primitive that covers a virtual sample location within a pixel. The virtual samples provide additional coverage information that may be used to adjust the weights of real samples.

Abstract: The present invention is applied, for example, to resolution conversion. An edge gradient direction v1 with the largest gradient of pixel values and an edge direction v2 orthogonal to the edge gradient direction v1 are detected. Edge enhancement and smoothing processing are performed in the edge gradient direction v1 and in the edge direction v2, respectively, to generate output image data D2.

Abstract: Disclosed is a method and an apparatus for dithering a pixel value in a image. The method includes checking a difference in chrominance signals between a particular pixel and a pixel adjacent to the particular pixel, in an input image, designating the particular pixel as being in a flat or a non-flat area in consideration of the difference in chrominance signals and dithering the particular pixel when the pixel is designated as being in the non-flat area.

Abstract: The embodiments of the present invention are a method and apparatus to perform anti-aliasing using multi-sampling on a non-power-of-two pixel grid. Using the present invention with 6 sample multisampling gives the same visual antialiasing quality as 8 samples using a prior art technique but uses less memory. A non-power-of-two equally spaced sample from a conventional grid of size N×N, where N is 12 can be chosen using the present invention. A scan conversion to determine the set of pixels covered by a polygon is performed in two parts. According to one embodiment, the present invention can multiply and divide by “N” in order to multisample an image using samples per pixel chosen from a N×N sub-sample grid, where “N” is not necessarily a power of 2. The present invention performs the divide by “N” step, where the step is achieved using a quick divide by 3 or 12 technique.

Abstract: An image processing method for reducing jaggy effect, which is applied in an image output device, is provided. Firstly, a continuous tone image is generated, and continuous tone pixels are defined according to a first addressing space. Then, a halftone image is generated. After that, the continuous tone image is low-pass filtered to generate a low-pass filtered image. Next, determine whether a position of the low-pass filtered image whose density is approximate to a pre-determined density. If so, generate a set of second addressing space co-ordinates of a key point corresponding to the position. Then, a moving vector corresponding to the key point is generated so as to regulate the position of a display point of the halftone pixel. Afterward, output the display point according to the position after regulation.

Abstract: A method for sharpening the corners of digital image data within an anti-aliasing image path so as to overcome corner rounding when displayed or printed. The method comprises stepping a window across the image data and comparing that windowed data to templates or performing Boolean logic and arithmetic operations on the image data. Upon determining a match or a corner detection, pixel values are substituted in the identified pixel locations to achieve a clustering of the substituted pixel values about the corner structure producing a corner-enhanced digital image. Filtering and sampling are then performed according to an anti-alias operation to the corner-enhanced image to produce an anti-aliased corner enhanced image. The data substitution will achieve a localized clustering or “ear” of toner/ink, or in the alternative for inside corners the localized clustered absence of toner/ink. The result of this clustering is a sharpening of the corners so that they display or print as intended by the bitmap.

Abstract: A method of removing ringing and blocking artifacts from a decompressed digital image. In one method, a background value of the digital image a background region and foreground regions is determined, and a threshold value is computed. A mapping of the digital image is then generated by thresholding the digital image based on the threshold value to produce a thresholded image, and enlarging the foreground regions of the thresholded image to form a map image. The mapping includes the background pixels of the map image. The background region of the decompressed digital image is then cleansed based on the mapping. In an alternate method, ringing artifacts are removed from a decompressed digital image based on a signal-to-noise ratio of the image. In yet another alternate embodiment, ringing artifacts are from a decompressed digital color image that includes a chrominance channel and a luminance channel. An alternate embodiment removes ringing and blocking artifacts.

Abstract: A domain block image is extracted from an original image by a domain block extracting section, and the domain block image is classified by a domain block classifying section. A range block extracting section extracts a range block image larger than the domain block image from the original image, and a reduced range block forming section reduces the range block image at the same size as the domain block image. A similarity degree judging section judges a similarity degree between the reduced range block image and the domain block image, and an improved domain block forming section performs a conversion of pixel values with respect to the reduced range block image in accordance with this similarity degree. Further, an edge enhancement processing section executes an edge enhancement processing as to the step edge portion so as to obtain an improved domain block image.

Abstract: An image processing apparatus includes: a memory that stores a background image and a character image that is separate from the background image and overlaps the background image; a processing target area determining unit that determines a processing target area in the background image, the processing target area being in a prescribed positional relation with the character image; a background feature parameter extracting unit that extracts from the processing target area a background feature parameter that includes a feature frequency showing a frequency characteristics of the processing target area; a character feature parameter extracting unit that extracts from the character image a character feature parameter that includes a feature frequency showing a frequency characteristics of the character image; a parameter determining unit that determines a parameter for use in image processing performed on the processing target area, according to a combination of the background feature parameter and the character

Abstract: An image processing method comprises analysing an image of a portion of text, and detecting the inter-line spacing and the inter-word spacing across the area of the image. Based on the inter-line and inter-word spacings, a quadrilateral shape is derived which represents the deformation of the text image from an undistorted image. The image is modified to perform perspective correction based on the derived quadrilateral.

Abstract: This invention obtains a high-quality output image in which a jaggy or a disconnection of a thin line hardly stands out. An edge detection unit detects whether the pixel of interest is an edge pixel or a non-edge pixel. A screen processing unit performs screen processing for the pixel of interest to determine the output value of the N-level tone. A calculation unit performs filtering processing having a preset visual sense characteristic for an area including the pixel of interest to calculate the target value of the pixel of interest, and corrects the value of the pixel of interest so as to come close to the target value, thereby determining the output value of the N-level tone. The selector selects, according to the detection result by the edge detection unit, either the result from the calculation unit or that from the screen processing unit.

Abstract: The teachings provided herein disclose an image processing method for rendering a digital image possessing anti-aliased pixels by selecting a target pixel location within the digital image; observing a set of pixels within a pixel observation window superimposed on the digital image relative to the target pixel location; generating edge-state codes for a plurality of pairs of neighboring vectors of pixels within the pixel observation window; generating edge-identification codes from the plurality of edge-state codes using at least one look-up table; and, utilizing the edge-identification codes to select and apply to the digital image at the target pixel either anti-aliased rendering or conventional halftoning. The anti-aliasing may employ pixel signals that are high addressable and directionally biased to a particular orientation.

Abstract: A document display method includes a determination step of determining, in a case that a display magnification of document data to be displayed is reduced, whether or not the display magnification of the document data is equal to or greater than a predetermined display magnification, and an applying step of applying smoothing processing to image data of the document data if it is determined that the display magnification of the document data is equal to or greater than the predetermined display magnification, and not applying the smoothing processing to the image data of the document data if it is determined that the display magnification of the document data is less than the predetermined display magnification. In addition, a display step displays the image data to which the smoothing processing has been applied in the applying step or the image data to which the smoothing processing has not been applied.

Abstract: A method of compensating a zipper image by a K-value, and a method of calculating the K-value. Whether the nth primitive pixel of the mth line is obtained by primary line scan is determined. If the nth primitive pixel of the mth line is obtained by primary line scan, the nth primitive pixel of the mth line is compensated as the nth primitive pixel of the mth line minus a sum of the (n?1)th primitive pixel of the (m?k)th line and the (n+1 )th primitive pixel of the (m?k)th line multiplied by the K-value. If the nth primitive pixel of the mth line is obtained by secondary line scan, the nth primitive pixel of the mth line is compensated as the nth primitive pixel of the mth line minus a multiplication of the K-value and a sum of the (n?1)th primitive pixel of the (m+k)th line and the (n+1)th primitive pixel of the (m+k)th line.

Abstract: Methods and apparatuses for anti-aliasing scan conversion. In one aspect of the invention, an exemplary method to scan convert an image on a data processing system includes: sampling the image in a first direction to generate first signals for points along a second line in a second direction using a closed form solution for a convolution integral with a first kernel; and weighting the first signals for the points according to a second kernel in the second direction to generate a second signal for a pixel. In one example according to this aspect, the closed form solution is tabulated in a look up table. After entries are looked up from the look up table according to the image along a first line in the first direction on a first point of the points, the entries are combined to generate one of the first signals for the first point.

Abstract: A method of generating a second bit map, improved in first-direction resolution, from a first bit map having a plurality of image-forming pixels arranged two-dimensionally, the method comprising a first detection step of detecting first and second edges appearing in a second direction orthogonal to a first direction in a first bit map, and the first addition step of adding at least an edge extending in the first direction, when a portion between the first and second edges permits interpolation, to between third and fourth edges on the second bit map respectively corresponding to the first and second edges so as to effect interpolation between the third and fourth edges. Since the first and second edges, if detected, permit smoothing, a look-up table is not needed, and even a long-range unevenness can be smoothed without a smoothing range being limited to a predetermined region.

Abstract: A sampling pattern covering an array of pixels for use in an anti-aliasing system is disclosed where each pixel has a pattern of sample points at the edges of the pixel. Moreover is the sample point pattern of each pixel a mirror image and different from the pattern of a directly neighboring pixel.

Abstract: The invention provides a pixel interpolating method including a step of discriminating, based on an input image signal, a similarity of a discrimination block constituted of plural pixels, and a reference block constituted of plural pixels, positioned close to the discrimination block and shifted upwards or downwards to a position by at least a line with respect to the discrimination block, and a step of outputting, as pixel information of an interpolation pixel positioned between a discrimination block and a reference block having a high similarity, pixel information based on pixel information of a pixel of the discrimination block and/or the reference block having the high similarity.

Abstract: Antialiasing method and apparatus for video applications. A method for antialiasing a video graphic. A determination is first made as to the relative position of a desired pixel being within the polygon and proximate to the edge of the polygon. Once the relative position is known, then a determination is made as to whether it meets a first predetermined condition or a second predetermined condition. If the relative position meets the first condition, then the color of at least an adjacent pixel is blended with the color of the desired pixel in a predetermined proportion. If the relative position meets the second predetermined condition, then the color of at least an adjacent pixel is blended with the color of the desired pixel in a predetermined proportion.

Abstract: A method and system for storing and generating anti-aliased text and lineart data from compressed document image files, using a MRC model that represents the image as an ordered set of mask/image pairs at resolutions appropriate to the content of each layer. The method and system provide the ability to generate for anti-aliased text data to improve appearance at both high and low resolution, and to avoid baseline jitter of compressed tokens.

Abstract: An image processing system. An input/output device receives information for pixels in an image corresponding to an object, wherein the information specifies optical properties. A storage device stores the information. A processor determines an image of preliminary contour of the object based on the information. For pixels located on the preliminary contour are assigned as primary pixels, wherein anchor points determined by the location of the primary pixels, and the reference pixels determine modification vectors according to the information corresponding to the primary and reference pixels, and adjusts the positions of the anchor points according to the modification vectors. These processes are applied on every pixels or selected pixels located on the preliminary contour repeatedly to determine the final modified contour with sub-pixel accuracy.

Abstract: An image processing apparatus includes a ridge strength detecting unit for detecting a ridge strength that is the strength of a ridge included in an image. When a pixel value is changed in the form of a pulse in accordance with a positional change in a region that includes a plurality of pixels, the ridge strength is represented by a gradient and height of the pulse.

Abstract: This invention relates to an image data processing method or the like capable of obtaining a preferable reproduction image based on processed image data even if the image data is short of the unit of block on reading the image data from the memory means in the unit of block. When image data of “M lines×N pixels” written in a memory is read in a unit of block consisting of the predetermined number of pixels and the read image data is subjected to a compression coding process or the like, if data of two lines and data of four pixels per line are short, data of two pixels per line is added to the left end side of the image by using data (1,1) (2,1) . . . (M,1) in the left end side thereof and data of two pixels is added to the right end side of the image by using data (1,N) (2,N) . . . (M,N) in the right end side thereof. Data of one line is added to the upper end side of the image by using data (1,1) (1,2) . . .

Abstract: An image output apparatus is provided with an image conversion unit for converting image data into an output image of intermediate gradation using a line screen for forming pixel points in stripes, an element angle storing unit for storing the angle information of line segments of the image data, a jaggy judging unit for judging whether or not jaggies will appear on the outline of the output image based on the angle information of the line segments stored in the element angle storing unit, and a screen angle setting unit for substantially changing the screen angle of the line screen if jaggies are judged to appear by the jaggy judging unit.

Abstract: A system and method that enhance edges in images by detecting and correcting edges of the components of the image, such as the luma and the chroma components. The luma and the chroma edges may be corrected to align with one another. The luma edge detection may utilize a combination of the first and second derivatives of luma. The chroma edges may be sharpened by adjusting the saturation of the chroma components, without changing the hue. The luma edges may be corrected using a blend of peaking and enhancing the luma edges. The corrected chroma and luma components may be then debugged and the appropriate corrected components may be sent to display. Chroma/luma edge alignment may utilize a product of the luma first and second derivatives.

Abstract: A method for interpolating a pixel within an image is provided. The image has a plurality of pixels arranged in a matrix format. The method includes: detecting if there is an edge in a block of the image according to frequency information of the block associated with the pixel; determining an interpolation direction for the pixel according to the detection result and the frequency information; and interpolating the pixel according to the determined interpolation direction. Additionally, a device for implementing the method is also provided.

Abstract: A method to remove ringing artifacts from locations near dominant edges of an image reconstructed after compression. The image is decomposed into blocks small enough so that each would contain only one significant edge. A significant edge is tested as to whether it is a dominant edge of the image. If there is no dominant edge, the block is not processed. In the remaining blocks, the exact pixels that include the dominant edges are output without filtering. The direction of the dominant edges is inferred, and then the remaining pixels are filtered with a directional de-ringing filter. The de-ringing filter has a main direction that is perpendicular with the direction of the edge, and thus also with an inherent direction of the ringing artifacts.

Abstract: Systems and methods of enhancing text-like edges in digital images are described. In one aspect, pixels in a block of image pixels are segmented into first and second pixel classes. The pixel block is edge enhanced in response to a determination that the pixel block likely contains at least one text-like edge based on a measure of distance separating intensity values respectively representing intensity distributions of the first and second classes and based on measures of peakedness of intensity histograms computed for both the first and second pixel classes.

Abstract: A method is provided for enhancing the details of an image while suppressing or preventing shoots that would otherwise occur during a prior art enhancement process. The enhancing method is based on recognizing that Shoots are likely to occur at edges of an image to be enhanced, and therefore, if the enhancement is sufficiently reduced or even possibly eliminated at the edges of the image, the Shoots that would otherwise occur will be suppressed or even possibly eliminated. A gain suppressing function is used to attenuate the enhancement at the edges of the image. Preferably, the gain suppressing function inherently identifies the edges of the image to be enhanced.

Abstract: Systems and methods for registering hemispheric images obtained using a fisheye lens for panoramic viewing, relating to spatial alignment and colour balancing of complement half-side images derived from the hemispheric images. The systems and methods for spatial alignment determine the displacement of the digitized recorded images using a single translation and rotation model of distortion, which further evaluates the centre of projection, and the extent of translation and rotation. The system and method for colour balancing iteratively increase (or decrease) the values of pixels near the edge (discontinuity) between the two half-sides of an image, each time taking into consideration the average difference of pixel colour across a smaller strip of the edge near the pixel. This invention removes the colour differential but does not remove any detail underlying the features of the image.

Abstract: When a print key on a console panel is depressed, a main CPU confirms enlargement/reduction rate information input via the console panel, and then, performs line thinning by setting a line thinning parameter according to the same magnification, an enlargement rate or a reduction rate in a line thinning processing unit in an image processing apparatus.

Abstract: Upscaling of an anti-aliased graphical element in a raster image includes generating a grid of pixels. Resolution of the grid is higher than resolution of the graphical element. Each pixel in the anti-aliased graphical element corresponds to a group of pixels in the higher resolution grid. The upscaling further includes distributing coverage of each transition pixel in the anti-aliased graphical element to the corresponding pixels in the higher resolution grid. The coverage is distributed unevenly.

Abstract: An edge enhancement system, including a selective edge controller for determining one or more properties of an edge of image data, and for generating one or more weighting factors on the basis of properties of the edge; and a scaling module for scaling an edge enhancement signal by the weighting factors to control the degree of edge enhancement. The image data may represent a still or moving (i.e., video) image. A max-min search circuit determines maximum and minimum turning points closest to the center of the data processing window and that are located on opposing sides of the window, to determine values and locations of maximum and minimum pixels of the edge. An edge-directed pre-filtering circuit reduces the amplification of edge fuzziness by smoothing close the edges vertical prior to enhancement. An aliasing protection circuit reduces the visibility of saw-tooth defects on predominantly horizontal diagonal edges.

Abstract: An edge amount detector detects an edge amount from RGB signals, and a filter processor synthesizes an output for edge enhancement with an output for smoothing at a proportion based on the detected edge amount. Another edge amount detector detects an edge amount of a black component from CMY signals, and an ink generator/undercolor remover changes an ink generation rate according to the detected edge amount.

Abstract: It is an object of the present invention to output a clear, expanded image wherein step-shapes or chain-shapes of oblique lines are reduced, distortion is eliminated and no constituent lines of fonts or graphics are missing.

Abstract: A method of modifying screened image data so that there is no visible seam when the image is printed repeatedly in a circumferential direction, for example using a drum output device. One version applicable to images screened using a supercell includes cutting the image so that the image size in the circumferential direction is an integral number of screen supercells. Another version includes displacing halftone dots in a neighborhood of the seam such that the seam is not visible in a repeated print.

Abstract: A graphics system has a mode of operation in which primitive coverage information is generated for real sample locations and virtual sample locations for use in anti-aliasing pixels. An individual pixel has a single real sample with color information and at least one virtual sample. In one implementation each virtual sample within a pixel is a pointer that identifies whether the virtual sample belongs to the single real sample within the pixel or to a proximate neighboring pixel. The virtual sample information permits a blending weight to be determined for blending color values of a partially covered pixel with color values of neighboring pixels.

Abstract: The device has flexure correcting means for operating to rotate a first eccentric cam provided at a central part of a first side of a reflecting mirror, thereby moving up and down the central part of the first side to correct the flexure of the reflecting mirror, torsion correcting means for operating to rotate a second eccentric cam or/and a third eccentric cam provided at the ends of a second side opposed to the first side of the reflecting mirror, thereby moving up and down both ends of the second side of the reflecting mirror to correct the torsion of the reflecting mirror, and a rotation operation portion provided at each of extended ends of camshafts provided at the eccentric cams to correct the flexure and torsion of the reflecting mirror.