Patents by Inventor Hisashi Ishikawa

Hisashi Ishikawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8406295
    Abstract: The present invention provides an image processing method and device which can both quickly and easily execute a pseudo halftone process with a large number of output gray levels and which can always execute the pseudo halftone process in the same manner regardless of the number of output gray scales. The present invention provides an image processing device that executes a pseudo halftone process on multivalued image data comprising a plurality of planes, the device including a component executing quantization and outputting for each of the plurality of density components, a component determining a correction value on the basis of a sign of a quantization error in each plane and a comparison of a sum of the quantization errors with a predetermined threshold, and a component correcting a value of the quantization output using the correction value and diffusing the quantization value.
    Type: Grant
    Filed: December 17, 2010
    Date of Patent: March 26, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventor: Hisashi Ishikawa
  • Publication number: 20130070789
    Abstract: There is provided an information processing apparatus including a plurality of communication units connected to one another in a ring shape by a bus, each of the plurality of communication units being connected to one of processing units, each of which executes a predetermined process, and transmitting data processed by the one of the processing units to the bus as a packet, the information processing apparatus transferring data between the processing units and processing the data in a predetermined order. Among the plurality of communication units, in at least one communication unit, a packet including a value indicative of suspension of the process is generated when the connected processing unit has suspended a process, and information showing whether or not the generation unit has generated the packet including the value indicative of suspension of the process is stored.
    Type: Application
    Filed: August 13, 2012
    Publication date: March 21, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yuji Hara, Hisashi Ishikawa
  • Patent number: 8388092
    Abstract: An image forming apparatus includes a print head provided with a plurality of discharge ports, a scanning unit configured to cause the print head to scan the same printing region on a recording medium a number of times, a generation unit configured to generate image forming data for each of scans, based on image information that has been input, and an image forming unit configured to perform image forming by discharging inks from the discharge ports on the recording medium according to the image forming data generated by the generation unit. The generation unit includes a division unit configured to divide the image information, while controlling division coefficients, using each of the discharge ports as the reference based on the division coefficients, and a quantization unit configured to quantize each of image information divided by the division unit.
    Type: Grant
    Filed: April 20, 2010
    Date of Patent: March 5, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shunichi Kaizu, Hisashi Ishikawa
  • Patent number: 8382228
    Abstract: An image forming apparatus which forms a halftone image on a print medium by using a multipass process to scan a printhead N (N is an integer of 2 or more) times in a single area on the print medium and form dots by each scan operation includes a pass division unit which sets the print density of a scan operation in the first pass so as to prevent dots from overlapping with each other on the print medium, and sets the print densities of scan operations in the second to Nth passes, a tone reduction unit which generates print data of the respective scan operations in accordance with the print densities set by the pass division unit, and a printhead which prints a halftone image on a print medium on the basis of the print data generated by the tone reduction unit.
    Type: Grant
    Filed: September 23, 2011
    Date of Patent: February 26, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tetsuo Uchiyama, Hisashi Ishikawa
  • Publication number: 20130010314
    Abstract: An image processing apparatus that converts input image data into printable image data is provided. The apparatus performs screen processing on the input image data, and determines whether moiré occurs in screen image data generated by the screen processing unit for a target pixel in the input image data. Depending on the determination result made by the determination unit, the apparatus outputs one of a screen pixel value in the screen image data for the target pixel and a value obtained by converting an input pixel value into a printable pixel value based on intermediate data, as a value of the target pixel in the printable image data, the intermediate data being generated by replacing a screen pixel in the screen image data that is determined to have moiré by the determination unit with the input pixel value in the input image data.
    Type: Application
    Filed: July 5, 2012
    Publication date: January 10, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Hisashi Ishikawa
  • Publication number: 20130013838
    Abstract: An information processing apparatus includes a plurality of modules connected in a ring shape via a bus, and each module processes a packet flowing in a single direction on the ring in a predetermined order. The module includes a communication unit for transmitting a packet received from a first direction in the ring via the bus to a second direction, a discrimination unit for discriminating a packet from among the packets received from the first direction as a processing packet to be processed by the module, and a processing unit which is connected with the communication unit one by one and configured to process the processing packet. The communication unit transmits the packet processed by the processing unit at an interval equivalent to processing time or more for a processing packet processed by a module in a latter stage in the predetermined order among packets transmitted by the communication unit to the second direction.
    Type: Application
    Filed: September 14, 2012
    Publication date: January 10, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Isao Sakamoto, Hisashi Ishikawa
  • Publication number: 20130003094
    Abstract: An image forming apparatus includes a color converting unit 330 for subjecting the input image data to a color conversion in accordance with ink color, and generating a print image 400; a print data generator 370-x for generating print data of each scan corresponding to multiple scans of the print image generated by the color converting unit 330; print controller 380-x for controlling at least one of the color converting unit 330 or print data generator 370-x based upon the input image data 320 or a position on a scanning line of each dot to be printed in the print image 400 generated by the color converting unit 330; and a printer engine 180 for printing on the print medium based upon the print data generated by the print data generator 370-x.
    Type: Application
    Filed: September 12, 2012
    Publication date: January 3, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Hiroyuki Horii, Hisashi Ishikawa
  • Patent number: 8335020
    Abstract: A 2-pixel averaging unit (101) halves an input image in the subscanning direction, and a multi-level error diffusion unit (102) performs multi-level error diffusion processing. A 2-pixel reconstruction unit (103) replaces each pixel with two pixels adjacent in the subscanning direction. A density value exchange unit (104) exchanges pixel values adjacent in the subscanning direction in each of 2×2 pixel blocks arranged in a checkered pattern in the image after replacement. High-density blocks each serving as a set of high-density dots and low-density blocks each serving as a set of low-density dots can be generated as 2×2 pixel blocks. The exposure region can be concentrated in PWM conversion.
    Type: Grant
    Filed: October 23, 2009
    Date of Patent: December 18, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventors: Go Araki, Yuuji Takayama, Tomoyuki Saiki, Hisashi Ishikawa
  • Patent number: 8325377
    Abstract: An image processing apparatus stores, in a buffer, an image data of c bits in the main scanning direction and y lines in the sub scanning direction, and reads out a pixel data of p bits that configures the image data stored in the buffer. Note that c is a common multiple of m, which is the number of bits in the unit of memory access, and p, which is the number of bits in a single pixel.
    Type: Grant
    Filed: December 1, 2011
    Date of Patent: December 4, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventors: Michiaki Takasaka, Hisashi Ishikawa
  • Patent number: 8320022
    Abstract: An image forming apparatus which forms a halftone image on a print medium (200) using multipass processing of scanning a single area on the print medium (200) by a printhead (220) N times and forming dots every scan operation includes a pass division table (410) used to set the print density ratio of each scan operation, a print data generation unit (370) which generates print data of each scan operation, a printer engine (180) which prints a halftone image on the print medium (200) on the basis of the generated print data, and a sensor (340) which detects the state of printing on the print medium (200) by the printer engine (180). The print data generation unit (370) corrects print data in synchronism with printing by the printer engine (180) on the basis of the set print density ratio and the detected printing state.
    Type: Grant
    Filed: April 27, 2012
    Date of Patent: November 27, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventors: Koichi Morishita, Hisashi Ishikawa
  • Publication number: 20120297392
    Abstract: The invention relates to an information processing apparatus, which comprises a plurality of communication units connected to a bus in a ring shape. At least one of the plurality of communication units extends a transmission interval when it is determined that the processing unit, which is to execute the next process for received data, is the processing unit, which executes the process after the processing unit corresponding to the at least one of the plurality of communication units, and when it is detected that the process for the received data is suspended.
    Type: Application
    Filed: May 15, 2012
    Publication date: November 22, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yuji Hara, Hisashi Ishikawa
  • Patent number: 8300535
    Abstract: An information processing apparatus includes a plurality of modules connected in a ring shape via a bus, and each module processes a packet flowing in a single direction on the ring in a predetermined order. The module includes a communication unit for transmitting a packet received from a first direction in the ring via the bus to a second direction, a discrimination unit for discriminating a packet from among the packets received from the first direction as a processing packet to be processed by the module, and a processing unit which is connected with the communication unit one by one and configured to process the processing packet. The communication unit transmits the packet processed by the processing unit at an interval equivalent to processing time or more for a processing packet processed by a module in a latter stage in the predetermined order among packets transmitted by the communication unit to the second direction.
    Type: Grant
    Filed: February 19, 2010
    Date of Patent: October 30, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventors: Isao Sakamoto, Hisashi Ishikawa
  • Patent number: 8295598
    Abstract: A processing apparatus processes input pixel data by referring to pixel data of peripheral pixels. The processing apparatus divides an input image in a first direction, inputs pixel data of a divided image divided in the first direction in a second direction crossing the first direction at a right angle, and stores the inputted pixel data. When a pixel to be referred to for processing the stored pixel data is not included in the divided image, the processing apparatus outputs pixel data of the reference pixel based on the stored pixel data, and processes the stored pixel data by referring to the pixel data of the reference pixel.
    Type: Grant
    Filed: December 18, 2008
    Date of Patent: October 23, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hirowo Inoue, Hisashi Ishikawa, Akitoshi Yamada
  • Patent number: 8289571
    Abstract: An image forming apparatus includes a color converting unit 330 for subjecting the input image data to a color conversion in accordance with ink color and generating a print image 400; a print data generator 370-x for generating print data of each scan corresponding to multiple scans of the print image generated by the color converting unit 330; print controller 380-x for controlling at least one of the color converting unit 330 or print data generator 370-x based upon the input image data 320 or a position on a scanning line of each dot to be printed in the print image 400 generated by the color converting unit 330; and a printer engine 180 for printing on the print medium based upon the print data generated by the print data generator 370-x.
    Type: Grant
    Filed: July 7, 2009
    Date of Patent: October 16, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroyuki Horii, Hisashi Ishikawa
  • Publication number: 20120250090
    Abstract: An apparatus for executing image processing by a plurality of serially connected image processing modules stores, in memory, set values for the plurality of image processing modules and image data to be processed by the plurality of image processing modules, adds headers to respective ones of the set values and image data that have been read out of the memory and transmits the result to a top image processing module among the plurality of image processing modules.
    Type: Application
    Filed: June 12, 2012
    Publication date: October 4, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Kenta Hosaki, Hisashi Ishikawa
  • Publication number: 20120219237
    Abstract: An image data combining apparatus combines m lines of image data that have been output from a reading unit. The reading unit outputs m lines of image data based upon the pixel data that has been output upon being divided into the plurality of lines, and stored then in a memory. An upper address for accessing the memory is decided based upon first data indicating position, along the sub-scan direction, of an image that has been read by the reading unit, and a lower address for accessing the memory is decided based upon second data indicating position of the image along the main-scan direction. For the lower address utilizes values in which the sequence of a plurality of bits constituting the first data is interchanged, so that p items of pixel data at a time are extracted successively from each of the m lines of image data.
    Type: Application
    Filed: May 2, 2012
    Publication date: August 30, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Hisashi Ishikawa, Yoshinari Ikegami
  • Publication number: 20120212751
    Abstract: An image forming apparatus which forms a halftone image on a print medium (200) using multipass processing of scanning a single area on the print medium (200) by a printhead (220) N times and forming dots every scan operation includes a pass division table (410) used to set the print density ratio of each scan operation, a print data generation unit (370) which generates print data of each scan operation, a printer engine (180) which prints a halftone image on the print medium (200) on the basis of the generated print data, and a sensor (340) which detects the state of printing on the print medium (200) by the printer engine (180). The print data generation unit (370) corrects print data in synchronism with printing by the printer engine (180) on the basis of the set print density ratio and the detected printing state.
    Type: Application
    Filed: April 27, 2012
    Publication date: August 23, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Koichi Morishita, Hisashi Ishikawa
  • Patent number: 8243084
    Abstract: A data processing apparatus includes a plurality of processing units each performing a respective one of process parts into which a predetermined process to be performed on data is divided, and a changing unit that changes a connection between the plurality of processing units on the basis of setting parameters that are set to enable a plurality of types of processing procedures.
    Type: Grant
    Filed: August 10, 2011
    Date of Patent: August 14, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventor: Hisashi Ishikawa
  • Patent number: 8238437
    Abstract: This invention scans a block using a window having a size of p×q pixels, and encodes p×q sub-block data each formed from pixel data at relatively identical positions in windows. A blocking unit receives a 16×16-pixel block image. A sub-block division unit scans the received block for each 2×2-pixel window, and generates 2×2 sub-block data each having a size of 8×8 pixels. Each sub-block is formed from pixel data at relatively identical positions in windows. A variable length coding unit encodes each sub-block data. When the sum of encoded sub-block data exceeds an allowable encoded data amount, a sub-block elimination unit eliminates encoded sub-block data until the sum becomes equal to or smaller than the allowable encoded data amount. The sub-block elimination unit outputs the remaining encoded sub-block data as encoded data of a block of interest.
    Type: Grant
    Filed: September 17, 2008
    Date of Patent: August 7, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventors: Noriyasu Hashiguchi, Hisashi Ishikawa, Kenta Hosaki
  • Patent number: 8223368
    Abstract: An apparatus for executing image processing by a plurality of serially connected image processing modules stores, in memory, set values for the plurality of image processing modules and image data to be processed by the plurality of image processing modules, adds headers to respective ones of the set values and image data that have been read out of the memory and transmits the result to a top image processing module among the plurality of image processing modules.
    Type: Grant
    Filed: September 22, 2008
    Date of Patent: July 17, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenta Hosaki, Hisashi Ishikawa