Adaptive Error Diffusion Patents (Class 358/3.05)
  • Patent number: 10306108
    Abstract: A halftone comprises a first halftone screen and a second halftone screen. The first halftone screen comprises a first plurality of amplitude modulated dots arranged according to a first plurality of rows, the first plurality of rows being orientated according to a first direction and comprising a first dot spacing. The second halftone screen comprises a second plurality of amplitude modulated dots arranged according to a second plurality of rows, the second plurality of row being orientated in a second direction and comprising a second dot spacing. The first direction and the second direction define an angle of 45 degrees or less and a ratio of the second dot spacing to the first dot spacing is less than one.
    Type: Grant
    Filed: July 19, 2018
    Date of Patent: May 28, 2019
    Assignee: HP Indigo B.V.
    Inventors: Tal Frank, Dror Kella, Boaz Tagansky, Oren Haik, Yotam Ben-Shoshan, Marina Limonov, Ram Dagan
  • Patent number: 10205850
    Abstract: An image processor sets the dot value to a value for forming a dot in a case where the dot forming condition is satisfied; sets the dot value to a value for forming no dot in a case where the dot forming condition is not satisfied and the target pixel is not the edge pixel; sets the dot value to a value for forming a dot in a case where the dot forming condition is not satisfied and a particular condition is satisfied; and sets a distribution error value to a smaller value than another error value in a case where the dot forming condition is not satisfied and the particular condition is satisfied and thereby the dot value is set to the value for forming a dot.
    Type: Grant
    Filed: September 15, 2017
    Date of Patent: February 12, 2019
    Assignee: BROTHER KOGYO KABUSHIKI KAISHA
    Inventor: Yasunari Yoshida
  • Patent number: 10136148
    Abstract: A method for managing a picture including pixels. In one aspect, a receiving device converts pixel values of the pixels represented with a first bitdepth into pixel values represented with a second bitdepth where the first bitdepth is smaller than the second bitdepth. The receiving device identifies a first group of pixels including a first pixel and a second pixel. The receiving device identifies a first and second edge pixel, derives a first and second pixel values based on the edge values of the first and second edge pixels, and estimates a first estimated pixel value for the first pixel based on the derived first pixel and second pixel value.
    Type: Grant
    Filed: December 22, 2015
    Date of Patent: November 20, 2018
    Assignee: TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
    Inventor: Martin Pettersson
  • Patent number: 9876965
    Abstract: A moving-image processing device (101) synthesizes a first moving image and a second moving image. In the first moving image, a first object is drawn, and accompanied by first-object depth information. In the second moving image, a second object is drawn, and accompanied by second-object depth information. A moving image generator (105) generates a third moving image in which the first moving image and the second moving image are synthesized. A clash determiner (103) serving as an interference determiner refers to the first-object depth information and the second-object depth information to determine whether the first object and the second object in the third moving image satisfy interference conditions. In cases when it is determined that the interference conditions are satisfied, a corrector (106) performs deforming transformation corresponding to correction of the shape of the trajectory of movement of the second object in three-dimensional space, thereby correcting the second moving image.
    Type: Grant
    Filed: September 7, 2012
    Date of Patent: January 23, 2018
    Assignee: Rakuten, Inc.
    Inventors: Rikio Onai, Makoto Okabe, Tatsuya Kurihara, Masahiro Sanjo, Hiromi Hirano
  • Patent number: 9847089
    Abstract: The present invention proposes a new method for improving the performance of a real-valued filterbank based spectral envelope adjuster. By adaptively locking the gain values for adjacent channels dependent on the sign of the channels, as defined in the application, reduced aliasing is achieved. Furthermore, the grouping of the channels during gain-calculation, gives an improved energy estimate of the real valued subband signals in the filterbank.
    Type: Grant
    Filed: December 28, 2016
    Date of Patent: December 19, 2017
    Assignee: Dolby International AB
    Inventors: Kristofer Kjoerling, Lars Villemoes
  • Patent number: 9560318
    Abstract: Apparatus and method for receiving and transmitting streaming live imagery data and audio signals in real time is provided. Imagery data and audio signals are acquired through a telestreamer input device and streamed to one or more remote recipients, allowing remote operators to electronically collaborate by telestrating, annotating, and sketching image overlays. Streaming video images displayed on a monitor are superimposed onto a virtual mesh projected via computer graphics. Vertices of the virtual mesh move according to a computational physics engine. Virtual tools are also superimposed onto a virtual mesh projected via computer graphics. The virtual tools interact with the virtual mesh to deliver real time, realistic modifications of the streaming image data. Recursive positioning of mesh layers and creation of a multi-layered virtual mesh enhance the realistic nature of the modified streaming image data.
    Type: Grant
    Filed: October 5, 2015
    Date of Patent: January 31, 2017
    Assignee: SKYSURGERY LLC
    Inventors: G. Anthony Reina, James Omer L'Esperance
  • Patent number: 9542950
    Abstract: The present invention proposes a new method for improving the performance of a real-valued filterbank based spectral envelope adjuster. By adaptively locking the gain values for adjacent channels dependent on the sign of the channels, as defined in the application, reduced aliasing is achieved. Furthermore, the grouping of the channels during gain-calculation, gives an improved energy estimate of the real valued subband signals in the filterbank.
    Type: Grant
    Filed: November 14, 2013
    Date of Patent: January 10, 2017
    Assignee: Dolby International AB
    Inventors: Kristofer Kjoerling, Lars Villemoes
  • Patent number: 9460491
    Abstract: A system and method convert a pixel of binary image data to a pixel of contone image data by determining if a predetermined pixel of binary image data is part of a solid edge or part of a fuzzy edge. A binary to contone conversion circuit converts the predetermined pixel of binary image data to a pixel of a first contone image data value, and a filter circuit converts the predetermined pixel of binary image data to a pixel of a second contone image data value. The filter circuit uses an adaptive filtering operation wherein the adaptive filtering operation utilizes one of a plurality of sets of weighting coefficients to change a characteristic of the filtering operation. The set of weighting coefficients used in the filtering operation are selected in response to a fuzzy edge detection. A selection between the first contone image data value and the second contone image data value is made based upon the determination as whether the predetermined pixel of binary image data is part of a solid edge.
    Type: Grant
    Filed: August 25, 2008
    Date of Patent: October 4, 2016
    Assignee: Xerox Corporation
    Inventors: Yingjun Bai, Xing Li
  • Patent number: 9355601
    Abstract: Processing data for a display including pixels, each pixel having color sub-pixels, comprises receiving pixel data. Once the pixel data is received, processing data for a display includes converting the pixel data to sub-pixel rendered data, the conversion generating the sub-pixel rendered data for a sub-pixel arrangement including alternating red and green sub-pixels on at least one of a horizontal and vertical axis. Next processing data for a display includes correcting the sub-pixel rendered data if a condition exists and outputting the sub-pixel rendered data.
    Type: Grant
    Filed: April 16, 2013
    Date of Patent: May 31, 2016
    Assignee: Samsung Display Co., Ltd.
    Inventor: Candice Hellen Brown Elliott
  • Patent number: 9142187
    Abstract: A semiconductor device includes an adjustment data generation unit receiving at least a part of adjustment values of color attributes of each of n-axis vertices (n is an integer not less than 3), the n axes serving as an adjustment axis in a RGB color space. The adjustment data generation unit calculates the degree of influence which indicates the following index of each of the n-axis vertices based on the distance between each of the n-axis vertices and a target point which is an arbitrary lattice point in the RGB color space. The adjustment data generation unit calculates adjusted coordinates of the target point in the RGB color space based on shifting of each of the n-axis vertices in the RGB color space according to the adjustment value and the degree of influence. The image adjustment unit performs color adjustment of inputted image data.
    Type: Grant
    Filed: April 11, 2013
    Date of Patent: September 22, 2015
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventor: Hirofumi Kawaguchi
  • Patent number: 9041980
    Abstract: Subdividing a color space is described for vector error diffusion which includes obtaining color coordinates for each primary color in the color space, and comparing the color coordinates to a threshold value for each coordinate plane of the color space. In response to the comparing, each primary color is grouped into a quadrant of the color space, wherein each quadrant is defined by the threshold value for each coordinate plane. In other aspects, a mapping a color to a closet primary color is described in a color space that includes a display determining color coordinates of the color and identifying a matching quadrant of a plurality of quadrants dividing the color space, wherein the determined color coordinates fall within the matching quadrant. A representative display device searches for the closest primary color within the matching quadrant and maps the color to the closest primary color found.
    Type: Grant
    Filed: January 20, 2013
    Date of Patent: May 26, 2015
    Assignee: QUALCOMM Incorporated
    Inventors: Huanzhao Zeng, Chong U. Lee, John H. Hong
  • Patent number: 8995019
    Abstract: An image processing apparatus includes an extracting unit extracting custom color identification data that identifies each of one or more custom colors different from multiple predetermined basic colors from drawing data for every page; a separation data generating unit generating separation data that indicates an object to be drawn for each color in accordance with the drawing data for one page without waiting for the completion of the extraction of the custom color identification data for the pages other than the one page; a raster data generating unit generating raster data concerning each color in accordance with the separation data; an acquiring unit acquiring mixing ratio data; and a combining unit combining the raster data concerning the custom color with the respective pieces of raster data concerning the basic colors in accordance with the mixing ratio data.
    Type: Grant
    Filed: May 15, 2013
    Date of Patent: March 31, 2015
    Assignee: Fuji Xerox Co., Ltd.
    Inventor: Yasushi Nishide
  • Patent number: 8953222
    Abstract: An image forming apparatus includes a printer engine, a storage unit, a print data interpreting unit, and a print control unit. The print data interpreting unit interprets print data and identifies both a first job type and a second job type. The first job type specifies any one of a special print job using special toner and a normal job using normal toner, and the second job type specifies a print function to be used. The print control unit makes a decision to permit or prohibit accumulation of print data in view of security based on the first job type and the second job type, accumulates the print data in the storage unit when the decision to permit the accumulation of the print data is made, and prohibits the accumulation of the print data when the decision to prohibits the accumulation of the print data is made.
    Type: Grant
    Filed: December 2, 2011
    Date of Patent: February 10, 2015
    Assignee: Ricoh Company, Limited
    Inventors: Hiroaki Kobayashi, Isamu Mitsuke, Takahiro Hirakawa, Saori Iura, Yuuichi Yoshida, Nobuyuki Iwata, Tomoyuki Takahira
  • Patent number: 8917425
    Abstract: An image processing apparatus includes processors which output first and second image data from input image data. The second image data is applied halftone processing of a higher resolution than halftone processing applied to the first image data. The image processing includes a unit configured to decide a mixing ratio of a pixel using a value based on a sum of an error of the pixel and a change amount of a pixel value at that pixel; and a mixing unit configured to mix pixel values of the first image data and the second image data according to the mixing ratios. When the value based on the sum is increased, the mixing ratio of the second image data decided by the decision unit remains the same or is increased.
    Type: Grant
    Filed: April 26, 2013
    Date of Patent: December 23, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventor: Hikaru Uchidate
  • Patent number: 8907955
    Abstract: A vector image drawing device has the following configuration. A contour generation unit (104), based on vector data, generates contour data that represents the starting pixels on a scan line in a drawing area where fill-in starts, and the ending pixels where fill-in ends. An outline buffer (106) stores the number of starting or ending pixels in the contour data for fill-in for each drawn pixel. An error judgment unit (2), when storing the contour data in the outline buffer (106), determines in which pixel there is overflow in the outline buffer of contour data. A pixel position transfer unit (3) adds the numerical value of the overflow portion of a pixel that the error judgment unit (2) determined to have overflow to the numerical value of contour data that corresponds to a pixel.
    Type: Grant
    Filed: November 9, 2009
    Date of Patent: December 9, 2014
    Assignees: NEC Soft, Ltd., NEC Solution Innovators, Ltd.
    Inventor: Hiroshi Fujiwara
  • Patent number: 8902470
    Abstract: An image processing apparatus includes: a multi-level unit that applies a multi-level process on binary halftone dot image data indicating a binary halftone dot image, to form multi-level image data; an acquiring unit that acquires a number of screen lines of the binary halftone dot image data; a tone correcting unit that determines a tone correction amount corresponding to the number of screen lines of the binary halftone dot image data acquired by the acquiring unit, and that applies tone correction on the multi-level image data produced by the multi-level unit, by using the determined tone correction amount; and a re-binarizing unit that binarizes the multi-level image data in which the tone is corrected by the tone correcting unit, without changing a halftone dot shape of the binary halftone dot image data, to produce re-binarized halftone dot image data.
    Type: Grant
    Filed: April 19, 2013
    Date of Patent: December 2, 2014
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Toru Misaizu, Kenji Hara, Shigeru Arai, Kota Matsuo
  • Patent number: 8885222
    Abstract: An image processor includes a color conversion unit that generates color converted image data by converting color data and an error diffusion process performing unit that generates print data by performing an error diffusion process on the color converted image data. The error diffusion process performs a first error diffusion process on remaining data and performing a second error diffusion process on edge data such that an amount of ink used in the edge region by performing the second error diffusion process on the edge data is less than an amount of ink used in the edge region by performing first error diffusion process on the edge data.
    Type: Grant
    Filed: January 19, 2012
    Date of Patent: November 11, 2014
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventor: Masashi Kuno
  • Patent number: 8867100
    Abstract: An image may be quantized into a pattern of dots, e.g., for devices capable of printing dots of variable size and variable color intensity. One may use a pre-determined mapping of the continuous-tone intensity value into a discrete vector of intensity values, and each intensity value may then be processed by a set of binary quantizers. The resulting binary vector may then be mapped into a combination of available dot sizes and color intensities. Through a scalar multiplier, the pre-determined mapping of continuous-tone intensity values may be used at multiple print resolutions.
    Type: Grant
    Filed: June 22, 2010
    Date of Patent: October 21, 2014
    Assignee: LRC Solutions, LLC.
    Inventors: Daniel L. Lau, Gonzalo R. Arce
  • Patent number: 8861035
    Abstract: A contone source image is processed to create halftone outputs by identifying intensity thresholds based on the coordinates of the pixels of the source image. The halftone output corresponding to a particular pixel of the contone image in a particular color plane is determined by comparing the intensity of the pixel and any previously accumulated output error to the intensity threshold corresponding to the pixel.
    Type: Grant
    Filed: March 24, 2014
    Date of Patent: October 14, 2014
    Assignee: Marvell International Ltd.
    Inventor: James Mealy
  • Patent number: 8824013
    Abstract: An image processing method suitable for a printer unit, includes an error diffusion halftoning process arranged for quantizing and diffusing each pixel of an image including a set of subtractive primary colors (C?, M?, Y?), in an image including a quantized printer image including a set of ink drops (DC, DM, DY, Dc, Dm) of respective ink channels to be printed. The method comprises the step of determining, for each pixel, an input variable value (S) representing a measure of solvent quantity that should be ejected by the printer unit for each pixel, the input variable value being computed on the basis of the value of a corresponding pixel of the image including the set of subtractive primary colors (C?, M?, Y?), and of inputting the determined input variable value (S) in the error diffusion halftoning process together with the values of the corresponding pixel. The invention further relates to the apparatus embodying the method.
    Type: Grant
    Filed: September 3, 2007
    Date of Patent: September 2, 2014
    Assignee: Sicpa Holding SA
    Inventors: Rosa Maria Figueras I Ventura, Ana Dimitrijevic, Kevin Fine, Serge Catarinussi
  • Patent number: 8810858
    Abstract: In a print control device, an executing unit executes an error diffusion process in which one of a first and second setting processes is executed. In the first setting process, the executing unit determines whether a first condition is satisfied. The first condition includes that the corrected value of the pixel data is larger than the first threshold value and that the first allowance condition determined by a first probability is satisfied. After the executing unit determines that the first condition is not satisfied, the executing unit determines whether a second condition is satisfied. The second condition includes that the corrected value of the pixel data is larger than the second threshold value. In the second setting process, the executing unit determines whether the second condition is satisfied. After the executing unit determines that the second condition is not satisfied, the executing unit determines whether the first condition is satisfied.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: August 19, 2014
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventor: Masashi Kuno
  • Patent number: 8810856
    Abstract: In an image processing device, a processor is configured to perform: (a) acquiring target image data representing an image including a plurality of pixels, where the target image data includes a plurality of sets of pixel data corresponding to the plurality of pixels, where the image includes an object having at least one pixel of the plurality of pixels; (b) detecting the object in the image based on the target image data; (c) determining characteristic data indicating a potential for an occurrence of banding in the object based on the target image data; (d) determining a parameter based on the characteristic data; and (e) executing a halftone process to determine, for each of the plurality of pixels, a dot to be found based on the corresponding set of pixel data by using the parameter.
    Type: Grant
    Filed: February 7, 2013
    Date of Patent: August 19, 2014
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventor: Yukinori Suzuki
  • Patent number: 8804196
    Abstract: In an error diffusion process, a random number acquiring unit acquires a random number included in a first random number range that depends on the gradation value of the target pixel data, in a case that the gradation value of the target pixel data is in a first range. The first correcting unit corrects the gradation value of the target pixel data into a first corrected gradation value by using the random number. The dot value setting unit sets a dot value of the target pixel data to either a first dot value or a second dot value. The first random number range corresponding to the gradation value smaller than the second threshold value includes a specific random number such that the first correcting unit corrects the gradation value into the first corrected gradation value greater than the second threshold value by using the specific random number.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: August 12, 2014
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventor: Masashi Kuno
  • Publication number: 20140204425
    Abstract: Subdividing a color space is described for vector error diffusion which includes obtaining color coordinates for each primary color in the color space, and comparing the color coordinates to a threshold value for each coordinate plane of the color space. In response to the comparing, each primary color is grouped into a quadrant of the color space, wherein each quadrant is defined by the threshold value for each coordinate plane. In other aspects, a mapping a color to a closet primary color is described in a color space that includes a display determining color coordinates of the color and identifying a matching quadrant of a plurality of quadrants dividing the color space, wherein the determined color coordinates fall within the matching quadrant. A representative display device searches for the closest primary color within the matching quadrant and maps the color to the closest primary color found.
    Type: Application
    Filed: January 20, 2013
    Publication date: July 24, 2014
    Applicant: QUALCOMM Incorporated
    Inventors: Huanzhao ZENG, Chong U. LEE, John H. HONG
  • Patent number: 8780413
    Abstract: Embodiments of the present disclosure provide a method comprising processing a first pixel of a continuous tone image to generate a first error, the first error representative of a difference between an input level and an output level associated with the first pixel; and in response to processing the first pixel, assigning a random error to a second pixel that is neighboring the first pixel, wherein the assigned random error is independent of the first error. Other embodiments are also described and claimed.
    Type: Grant
    Filed: January 26, 2011
    Date of Patent: July 15, 2014
    Assignee: Marvell International Ltd.
    Inventors: Richard I. Klaus, Randall D. Briggs
  • Patent number: 8773713
    Abstract: An image processing apparatus including: a calculation portion that calculates a first process time period required for a case where image processes are executed by a reconfiguration process mode, and a second process time period required for a case where the image processes are executed by a pipeline process mode, based on the number of pixels of image information of an input print job and contents of processes of the input print job; and an activation portion that activates a plurality of dynamic reconfigurable processors (DRPs) according to a process mode having a shorter time period in the first process time period and the second process time period.
    Type: Grant
    Filed: September 10, 2010
    Date of Patent: July 8, 2014
    Assignee: Fuji Xerox Co., Ltd.
    Inventor: Susumu Kimura
  • Patent number: 8760725
    Abstract: A method and system for generating a halftone image from an input image is disclosed. The method and system use error distribution and threshold perturbation that is based on the incoming tone value. A threshold bias table may be generated in real time for each incoming tone value. The values of the threshold bias tables are selected so that certain positions are forced to include a dot, in the case of light tone values, or not include a dot, in the case of dark tone values. A halftone process that uses threshold bias tables based on the incoming tone can reduce unnatural patterns in the image apparent to the casual observer, which results in a more pleasing image.
    Type: Grant
    Filed: November 12, 2009
    Date of Patent: June 24, 2014
    Assignee: Marvell International Ltd.
    Inventor: Douglas G. Keithley
  • Patent number: 8693021
    Abstract: Described herein is a printing system including a plurality of print processing modules which can selectively transfer print media there between during printing. The system further including a controller that can predict the impending unhealthy state of at least one module and redirect one of an unprocessed job and a partially processed job preemptively from an impending unhealthy module to selectively one of a healthy module and another unhealthy module, with suitable characteristics, to process unprocessed portions of the job.
    Type: Grant
    Filed: January 23, 2007
    Date of Patent: April 8, 2014
    Assignee: Xerox Corporation
    Inventors: Meera Sampath, Stan Alan Spencer, Rajinderjeet Singh Minhas
  • Patent number: 8693057
    Abstract: A computer-readble medium stored with a program causing a computer to quantize a gray level causes the computer to perform a pixel selecting process; determining a noise use rate indicating the degree to which a dither matrix noise has an influence on the quantization and an error use rate indicating the degree to which an accumulated error has an influence on the quantization and determining the noise use rate and the error use rate corresponding to the corresponding pixel depending on the gray levels of the pixels sequentially selected in the pixel selecting process; and performing the quantization on the gray levels of the pixels sequentially selected in the pixel selecting process and performing the quantization using the dither matrix noise based on the noise use rate corresponding to the corresponding pixel and using the accumulated error based on the error use rate corresponding to the corresponding pixel.
    Type: Grant
    Filed: September 28, 2009
    Date of Patent: April 8, 2014
    Assignee: Mimaki Engineering Co., Ltd.
    Inventor: Kenji Harayama
  • Patent number: 8681382
    Abstract: A contone source image is processed to create halftone outputs by identifying intensity thresholds based on the coordinates of the pixels of the source image. The halftone output corresponding to a particular pixel of the contone image in a particular color plane is determined by comparing the intensity of the pixel and any previously accumulated output error to the intensity threshold corresponding to the pixel.
    Type: Grant
    Filed: November 3, 2011
    Date of Patent: March 25, 2014
    Assignee: Marvell International Ltd.
    Inventor: James Mealy
  • Publication number: 20130321871
    Abstract: An image processing apparatus includes processors which output first and second image data from input image data. The second image data is applied halftone processing of a higher resolution than halftone processing applied to the first image data. The image processing includes a unit configured to decide a mixing ratio of a pixel using a value based on a sum of an error of the pixel and a change amount of a pixel value at that pixel; and a mixing unit configured to mix pixel values of the first image data and the second image data according to the mixing ratios. When the value based on the sum is increased, the mixing ratio of the second image data decided by the decision unit remains the same or is increased.
    Type: Application
    Filed: April 26, 2013
    Publication date: December 5, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Hikaru Uchidate
  • Patent number: 8599439
    Abstract: An apparatus and a method are described for processing and reproducing a document including both text and half-tone images without generating undesirable image artifacts. A band-pass FIR filter with a predetermined frequency response is used to transform pixels in an input image to sharpen text edge and smooth pre-half-toned areas, and perform error diffusion and cluster dot screening methods on the transformed pixels. The FIR filter has unity gain at DC to preserve image brightness. An integrated error diffused cluster-dot screening approach is used to suppress moiré and other image artifacts, while providing a robust, crisp output.
    Type: Grant
    Filed: September 19, 2008
    Date of Patent: December 3, 2013
    Assignee: CSR Imaging US, LP
    Inventors: Shenbo Yu, Fred W. Andree, Steven J. Pratt
  • Patent number: 8577162
    Abstract: An output apparatus determines pixels that form an area equal to or greater than a predetermined size and whose pixel values are not different from pixel values of neighboring pixels, and pixels that form an area not equal to or greater than the predetermined size. The apparatus reduces the pixel values of the determined pixels and outputs a binary image formed by the determined pixels with the reduced pixel values.
    Type: Grant
    Filed: August 11, 2010
    Date of Patent: November 5, 2013
    Assignee: Fujitsu Limited
    Inventor: Shouichi Kuboyama
  • Patent number: 8576447
    Abstract: Error diffusion halftoning includes using a quantizer having an input and an output; and using a system having a bandpass characteristic to modify the quantizer input without feeding the quantizer output directly into the quantizer input. The error diffusion halftoning can produce clustered pixel halftone patterns that can be reliably reproduced by laser printers and other electro-photographic devices.
    Type: Grant
    Filed: October 31, 2003
    Date of Patent: November 5, 2013
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: Niranjan Damera-Venkata
  • Patent number: 8570602
    Abstract: A digital halftoning method and a method for constructing a class tiling map are disclosed. The present invention utilizes to arrange class matrixes in a staggering form such that adjacent class matrixes exist a staggering shift. Also, the class tiling map is constructed in this way. Then, a dot diffusion procedure is performed to an original image with the class tiling map so as to generate a halftone image corresponding to the original image. The present invention is capable of solving the problem of a periodic appearance caused by traditional dot diffusion.
    Type: Grant
    Filed: June 3, 2011
    Date of Patent: October 29, 2013
    Assignee: National Taiwan University of Science and Technology
    Inventors: Jing-ming Guo, Yun-fu Liu
  • Patent number: 8564838
    Abstract: An image processing apparatus quantizes multi-level image data of n colors, where n?2, by performing an error diffusion processing. The image processing apparatus includes: a dot arrangement determining unit that determines either one of an essential dot count and an essential recording material amount when the multi-level image data of n colors is converted into multi-level image data of m colors, where n>m?1, by the error diffusion processing; and a color arrangement determining unit that performs the error diffusion processing on each color component of the multi-level image data of n colors, calculates either one of a dot count and a recording material amount for each color component, and determines an arrangement of either one of the dot count and the recording material amount for each color component within a range of a corresponding one of the essential dot count and the essential recording material amount determined by the dot arrangement determining unit.
    Type: Grant
    Filed: September 14, 2009
    Date of Patent: October 22, 2013
    Assignee: Ricoh Company, Limited
    Inventors: Arata Yamaguchi, Hiroaki Sagae, Takashi Kimura, Masakazu Yoshida
  • Patent number: 8503031
    Abstract: The image processing apparatus executes quantization processing of second multi-valued image data that corresponds to a second relative movement of a plurality of relative movements based on first multi-valued image data that corresponds to a first relative movement of the plurality of relative movements, and executes quantization processing of the first multi-valued image data based on the second multi-valued image data. This makes it possible to output a high-quality image having excellent robustness and reduced graininess by controlling the overlap rate of dots that are printed by the first relative movement and the dots that are printed by the second relative movement.
    Type: Grant
    Filed: December 7, 2010
    Date of Patent: August 6, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventors: Rie Kajihara, Akitoshi Yamada, Mitsuhiro Ono, Tomokazu Ishikawa, Yuji Konno, Yutaka Kano, Hitoshi Nishikori, Norihiro Kawatoko
  • Patent number: 8482801
    Abstract: A method and system for processing image data in an image processing device for a plurality of pixel positions within a plurality of scanlines. The method and system includes storing a starting stamp value and a plurality of delta stamp values for the scanline. The stored values being used to generate a pixel stamp value for an input pixel in the scanline, by adding a starting value or previous pixel stamp value and the stored delta stamp value for the input pixel. Further includes receiving an input pixel intensity value for the input pixel and determining an output pixel intensity value. Subsequently, if the output pixel intensity value for the input pixel is equal to a value for a dot or hole the delta stamp values for at least one pixel having a location previous or subsequent to the input pixel can be updated.
    Type: Grant
    Filed: April 10, 2008
    Date of Patent: July 9, 2013
    Assignee: Xerox Corporation
    Inventors: David Allen Mantell, John Adam Handwork, David Metcalfe
  • Patent number: 8482798
    Abstract: A plurality of color data respectively undergo quantization processing, and a logical multiplication of the plurality of quantized color data is calculated. A product of the plurality of color data is calculated. A first low frequency component is extracted from the logical multiplication, and a second low frequency component is extracted from the product. The first low frequency component is subtracted from each of the plurality of color data, and the second low frequency component is added to the subtraction results to generate a plurality of corrected color data. The plurality of corrected color data respectively undergo the quantization processing.
    Type: Grant
    Filed: June 23, 2010
    Date of Patent: July 9, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kaori Taya, Tomokazu Yanai
  • Publication number: 20130163010
    Abstract: A print control device acquires image data. Each pixel data has a gradation value represented by a first number of levels of gradation. The print control device acquires a first error matrix and a second error matrix and generates print image data representing an image by performing a halftone process on the image data using the first and second error matrices to convert each gradation value in the image data into a set of dot data. Each dot data represents one of a second number of types of dot formation. The second number is smaller than the first number. The print control device uses the first error matrix for pixel data corresponding to a pixel to be printed in a forward direction. The print control device uses the second error matrix for pixel data corresponding to a pixel to be printed in a reverse direction.
    Type: Application
    Filed: September 28, 2012
    Publication date: June 27, 2013
    Applicant: BROTHER KOGYO KABUSHIKI KAISHA
    Inventor: BROTHER KOGYO KABUSHIKI KAISHA
  • Patent number: 8437046
    Abstract: This presents an image processing apparatus and an image processing method which print and output image data subjected to halftone processing with an appropriate density characteristic. The image processing apparatus generates a halftone image from a multi-value image using a threshold value arrangement, and generates a difference image between the generated halftone image and a second halftone image having the density characteristic different from that of the generated halftone image. The image processing apparatus stores the generated halftone image and the generated difference image.
    Type: Grant
    Filed: September 8, 2009
    Date of Patent: May 7, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventor: Masahito Yamazaki
  • Patent number: 8422079
    Abstract: It is determined whether the pixel of interest in image data to be processed belongs to area 1 not close to a scan line changing point where a scan line changing process is done (S101). If the pixel of interest belongs to area 1, an error diffusion process is performed using an error diffusion matrix for area 1 (S102). If the pixel of interest belongs to area 2 close to the scan line changing point, the error diffusion process is performing using an error diffusion matrix for downward scan line changing for area 2 when the scan line changing process is changing to a lower line, or an error diffusion matrix for upward scan line changing for area 2 when the scan line changing process is changing to an upper line.
    Type: Grant
    Filed: July 24, 2008
    Date of Patent: April 16, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventor: Yasuyuki Nakamura
  • Patent number: 8422080
    Abstract: An image processing apparatus 101 that generates output image data based on multi-level image data is provided with an error diffusion processing unit 104 that generates tone pixel data from the pixel-of-interest data according to an error diffusion method, a dither processing unit 103 that generates tone pixel data from the pixel-of-interest data according to a dither processing method, an allotment ratio determination unit 105 that increases the allotment ratio with respect to the error diffusion method as the difference between the maximum density and the minimum density increases, and a composition unit 109 that composites the tone pixel data for a pixel of interest that has been generated by the error diffusion processing unit 104 and the dither processing unit 103 according to the allotment ratios determined by the allotment ratio determination unit 105, and outputs the composited data as pixel data of the output image data.
    Type: Grant
    Filed: December 23, 2009
    Date of Patent: April 16, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tomoyuki Saiki, Go Araki, Yuuji Takayama, Hisashi Ishikawa
  • Patent number: 8416457
    Abstract: A printing apparatus is adapted to perform printing of image data corresponding to a plurality of pixels representing a predetermined image. The printing apparatus includes a halftone processing section including a comparison section and an error diffusion section. The comparison section is configured to compare, for at least one of the pixels, a related grayscale value relating to a data grayscale value of the input image data with a corresponding one of a plurality of thresholds included in a dither mask. The error diffusion section is configured to generate dot data for indicating the presence or absence of formation of a dot in each of the pixels according to an error diffusion method, on the basis of the data grayscale values of the input image data, and to control the easiness of the dot formation according to the error diffusion method, on the basis of a comparison result of the comparison section.
    Type: Grant
    Filed: July 6, 2010
    Date of Patent: April 9, 2013
    Assignee: Seiko Epson Corporation
    Inventor: Toshiaki Kakutani
  • Patent number: 8405876
    Abstract: When multi-pass printing is performed, the dot overlap rate (ratio of the number of dots that overlap and are to be printed in the same pixel area by the plurality of relative movements with respect to the total number of dots to be printed in a pixel area by the plurality of relative movements) in pixel areas having medium-density where density unevenness caused by density fluctuation easily stands out is made higher than the dot overlap rate in pixel areas having low-density and pixel areas having high-density. By doing so density unevenness caused by density fluctuation is suppressed. In addition, the dot overlap rate in pixel areas having low-density and pixel areas having high-density is low, so it is possible to reduce graininess in low-density areas and suppress a decrease in density in high-density areas.
    Type: Grant
    Filed: June 11, 2010
    Date of Patent: March 26, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akihiko Nakatani, Fumihiro Goto, Akitoshi Yamada, Mitsuhiro Ono, Okinori Tsuchiya, Fumitaka Goto, Takashi Fujita, Rie Kajihara, Ayumi Sano, Tomokazu Ishikawa
  • Patent number: 8390891
    Abstract: A quantizing unit, error detector, error diffusion matrix, and adder quantize a pixel of interest of an input image by an error diffusion method. A calculation unit and gain adjuster calculate a value to be added to the pixel of interest with reference to quantized pixels. The adder adds the calculated value to the pixel of interest. A control unit controls the calculation of the gain adjuster.
    Type: Grant
    Filed: March 29, 2012
    Date of Patent: March 5, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventor: Naoto Kawamura
  • Patent number: 8368979
    Abstract: An image forming apparatus includes a tone correction storage unit that stores a plurality of tone correction charts for correcting tone of image data; a determination unit that determines characteristics of the image data; a selection unit that selects a tone correction chart suitable for the image data from the plurality of tone correction charts stored in the tone correction storage unit; a chart print unit that prints the tone correction chart selected by the selection unit on a sheet; a receiving unit that receives an adjustment value inputted based on the tone correction chart printed by the chart print unit; a tone correction unit that corrects tone of the image data based the adjustment value; and a print unit that prints out the image data after correcting tone of the image data.
    Type: Grant
    Filed: August 17, 2009
    Date of Patent: February 5, 2013
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Kiyoshi Une, Takaya Nagasaki, Hiroyuki Kawai, Yasuo Komatsu, Seiji Shiraki, Takumi Nishikata
  • Patent number: 8363278
    Abstract: The present invention relates to a method and apparatus capable of generating frequency-modulation halftone dots in high speed and belongs to the field of the digital image halftone. In the prior art, read-write operation is usually carried out many times in error rows during processing each pixel so that halftone dots are generated in low speed. In the method according to the present invention, the error generated by the current pixel is buffered in a register file and the final accumulated error values are written in the error rows only after all of the relative pixels are processed. Thus, read-write operation is carried out only once in the error rows for processing each pixel. The present invention also provides an apparatus to implement the method. The apparatus comprises an error row memory, an error buffer register file, a gray generation circuit, a threshold comparison circuit, an error generation circuit, an error buffer register file control circuit, and an error row control circuit.
    Type: Grant
    Filed: March 31, 2006
    Date of Patent: January 29, 2013
    Assignees: Peking University Founder Group Co., Ltd., Beijing Founder Electronics Co., Ltd., Peking University
    Inventors: Zhihong Liu, Feng Chen, Bin Yang
  • Patent number: 8363282
    Abstract: A method of processing a continuous tone image includes using a halftone screen to generate a bi-level bitmap; partitioning the contone image into an array of image blocks; halftoning the image blocks; using the bi-level bitmap to select some of the halftone image blocks; and modifying the selected halftone image blocks using code words, such that information contained in the code words is embedded in a halftone image. A method of extracting embedded information in a halftone image includes accessing a bi-level bit map; partitioning the halftone image into a plurality of image blocks; using the bitmap to select at least some of the blocks; identifying a code word sequence in the selected blocks; and extracting the information from the code word sequence.
    Type: Grant
    Filed: October 31, 2003
    Date of Patent: January 29, 2013
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: Niranjan Damera-Venkata
  • Patent number: 8363271
    Abstract: A method for controlling an image processing apparatus includes obtaining image data from a detachable memory unit, estimating whether the obtained image data is image data read by a scanner, and in a case where it is estimated that the obtained image data is image data read by the scanner, performing control not to execute predetermined screen processing on the image data.
    Type: Grant
    Filed: June 5, 2009
    Date of Patent: January 29, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoshiharu Ikegawa, Koki Shibao