Patents by Inventor Masaki Yamakawa

Masaki Yamakawa 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: 9167193
    Abstract: A display device is provided that controls, considering affection due to a watcher's age and his viewing distance as human-visual characteristics, a display-screen brightness level at which the watcher does not feel glare. The display-screen brightness is most suitably set by simple calculation using relationships among watcher's ages, display sizes, glare levels, and screen-illuminance levels, etc. obtained by a subjective-assessment experiment. According to this display device, considering watcher's various conditions such as the age, the visual acuity, and the viewing distance, even if the watcher watches the display for a relatively long time, the watcher does not feel tiredness; thus, comfortable watching can be achieved.
    Type: Grant
    Filed: April 5, 2007
    Date of Patent: October 20, 2015
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Yoshitomo Nakamura, Masaki Yamakawa, Emiko Kido, Satoru Kubota
  • Patent number: 7515211
    Abstract: A video signal processing circuit that uses a prescribed clock signal to process a digitized composite video signal. A clock generating means (2) generates the prescribed clock signal; a burst phase detecting means (3) detects color subcarrier phase information (p) in each line of the composite video signal; a phase difference calculation means (4) finds the phase difference between phase information (p) from the burst phase detecting means and a prescribed reference phase; a sampling phase conversion means (8) corrects the sampling phase of the composite video signal according to phase corrections (?b, ?t) obtained from the phase difference calculation means (4); a Y/C separation means (9) separates the luminance and chrominance signals from the composite video signal output from the sampling phase conversion means (8). Excellent two- or three-dimensional Y/C separation can be obtained regardless of the television broadcast system, even from a non-standard signal.
    Type: Grant
    Filed: August 25, 2004
    Date of Patent: April 7, 2009
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Masako Asamura, Yoshito Suzuki, Toshihiro Gai, Koji Minami, Masaki Yamakawa
  • Patent number: 7436382
    Abstract: A correction data output device according to the invention includes correction data outputting device for outputting correction data that corrects object frame data included in an inputted image signal on the basis of the mentioned object frame data and previous frame data, which are one frame period previous to the object frame data, and correction data correcting device for correcting correction data that corrects and outputs the correction data outputted from the mentioned correction data outputting device on the basis of the mentioned object frame data and the mentioned previous frame data.
    Type: Grant
    Filed: October 3, 2003
    Date of Patent: October 14, 2008
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Noritaka Okuda, Jun Someya, Masaki Yamakawa
  • Patent number: 7429994
    Abstract: A method of changing edge sharpness of an input image being formed from input pixels having intensity levels, the method including detecting pixel-to-pixel variations in the intensity levels in at least one direction in the input image, thereby generating local pixel variation patterns; determining a localized zoom ratio based on the local pixel variation patterns; controlling edge sharpness by changing the localized zoom ratio setting interpolation points with spacing between the interpolation points varying based on the localized zoom ratio and a basic zoom ratio; and generating output pixels from the input pixel by interpolation at the interpolating points.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: September 30, 2008
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Jun Someya, Masaki Yamakawa, Yoshiaki Okuno, Hideki Yoshii
  • Patent number: 7330199
    Abstract: An image is processed by detecting pixel-to-pixel variations in brightness level, generating high spatial frequency information related to the variations, setting interpolation points with a spacing that varies according to the high spatial frequency information, and generating new pixels by interpolation at the interpolation points. By increasing the zoom ratio in one part and reducing the zoom in another part of each edge in a continuous manner, this method can mitigate edge degradation when an image is enlarged or reduced, without introducing discontinuities or other image artifacts. It also provides a convenient way to adjust edge sharpness in an image.
    Type: Grant
    Filed: November 20, 2003
    Date of Patent: February 12, 2008
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Jun Someya, Masaki Yamakawa, Yoshiaki Okuno, Hideki Yoshii
  • Patent number: 7327340
    Abstract: A liquid-crystal driving circuit has an image data processor that, for example, encodes the present image, decodes the encoded image, delays the encoded image by one frame interval, decodes the delayed encoded image, and uses the two decoded images to generate compensation data for adjusting the gray-scale values in the present image. The encoding process reduces the amount of image data, thereby reducing the size of the frame memory needed to delay the image. The compensation data preferably cause the liquid crystal to reach transmissivity values corresponding to the gray-scale values of the present image within substantially one frame interval. This enables the response speed of the liquid crystal to be controlled accurately.
    Type: Grant
    Filed: January 21, 2004
    Date of Patent: February 5, 2008
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Jun Someya, Masaki Yamakawa
  • Patent number: 7313317
    Abstract: The portable image recording apparatus comprises a coding unit which codes an input sound and image data relating to an image, a parameter setting unit which variably sets a frame rate and a bit rate of coding to be executed by the coding unit according to a type of contents of the image; and a recording unit which records the coded data obtained by the coding unit into a small-sized recording medium.
    Type: Grant
    Filed: December 14, 2001
    Date of Patent: December 25, 2007
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Masashi Mori, Kunio Nakaoka, Hiroaki Sakai, Yoshinari Sugegaya, Akihiko Naito, Masaki Yamakawa
  • Publication number: 20070285569
    Abstract: A display device is provided that controls, considering affection due to a watcher's age and his viewing distance as human-visual characteristics, a display-screen brightness level at which the watcher does not feel glare. The display-screen brightness is most suitably set by simple calculation using relationships among watcher's ages, display sizes, glare levels, and screen-illuminance levels, etc. obtained by a subjective-assessment experiment. According to this display device, considering watcher's various conditions such as the age, the visual acuity, and the viewing distance, even if the watcher watches the display for a relatively long time, the watcher does not feel tiredness; thus, comfortable watching can be achieved.
    Type: Application
    Filed: April 5, 2007
    Publication date: December 13, 2007
    Applicant: Mitsubishi Electric Corporation
    Inventors: Yoshitomo Nakamura, Masaki Yamakawa, Emiko Kido, Satoru Kubota
  • Patent number: 7289161
    Abstract: In the case where an input signal is an interlace signal such as NTSC signal, a flicker interference as aliasing interference brought about by the sampling theorem is contained in a region where a vertical frequency component is high. Accordingly, in the conventional processing in which rate of change in gradation is improved by making a drive voltage of liquid crystal at the time of change in gradation larger than normal liquid crystal drive voltage to increase response rate of the liquid crystal panel, interference component is also emphasized. As a result, quality level of a video picture to be displayed on the liquid crystal panel is deteriorated. The invention provides a compensation device capable of improving rate-of-change in gradation at a part where there is no flicker interference and changing rate-of-change in gradation to suppress the flicker at a part where there is any flicker interference.
    Type: Grant
    Filed: October 1, 2003
    Date of Patent: October 30, 2007
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Masaki Yamakawa, Hideki Yoshii, Noritaka Okuda, Jun Someya
  • Patent number: 7224407
    Abstract: A color demodualation device having an AD converter, a phase signal generator, a burst data generator and a multiplier. The AD converter produces digital samples of chrominance signal at a frequency four times a color subcarrier frequency, and the phase signal generator generating a phase signal for identifying phases of a burst signal and color subcarrier signals modulated by respective B-Y and R-Y signals. The burst data generator produce burst data corresponding to the burst signals modulated by respective B-Y and R-Y signals. The burst respective color subcarrier signals according to the phase signal. The multiplier produces products of the burst data and the digital samples of the chrominance signal, from which digital samples of the respective R-Y and B-Y signals are produced.
    Type: Grant
    Filed: July 5, 2002
    Date of Patent: May 29, 2007
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hideki Yoshii, Masaki Yamakawa, Jun Someya, Yoshiaki Okuno
  • Publication number: 20060290818
    Abstract: A video signal processing circuit that uses a prescribed clock signal to process a digitized composite video signal. A clock generating means (2) generates the prescribed clock signal; a burst phase detecting means (3) detects color subcarrier phase information (p) in each line of the composite video signal; a phase difference calculation means (4) finds the phase difference between phase information (p) from the burst phase detecting means and a prescribed reference phase; a sampling phase conversion means (8) corrects the sampling phase of the composite video signal according to phase corrections (?b, ?t) obtained from the phase difference calculation means (4); a Y/C separation means (9) separates the luminance and chrominance signals from the composite video signal output from the sampling phase conversion means (8). Excellent two- or three-dimensional Y/C separation can be obtained regardless of the television broadcast system, even from a non-standard signal.
    Type: Application
    Filed: August 25, 2004
    Publication date: December 28, 2006
    Inventors: Masako Asamura, Yoshito Suzuki, Toshihiro Gai, Koji Minami, Masaki Yamakawa
  • Patent number: 7082226
    Abstract: A duplicated part of identical images in an encoded image data master is judged to be selected. Image data to be reused is generated by adding a storage instruction to encoded image data of the duplicated part of the first identical image, and converting encoded image data of the duplicated part of the second identical image into a reuse instruction. In a reproduction process, decoded data in the encoded image data part including the storage instruction is stored in a vacant area and the decoded data is read at the point of the reuse instruction.
    Type: Grant
    Filed: May 15, 2002
    Date of Patent: July 25, 2006
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoshinari Sugegaya, Kunio Nakaoka, Hiroaki Sakai, Masashi Mori, Akihiko Naito, Masaki Yamakawa
  • Patent number: 7034788
    Abstract: A coding circuit codes present image data of a pixel which is received as raster data and a delay circuit stores a coded image data for one frame period and outputs one-frame preceding image data of the pixel in accordance with an input of the coded image data. First and second decoder circuits decode coded image data and one-frame preceding coded image data, respectively, a variation-amount calculation circuit calculates variation-amount data of both decoded image date, and an one-frame preceding image reproduction circuit reproduces one-frame preceding reproduced image data. An image date correction circuit generates corrected present image data on the basis of the present image data and the one-frame preceding reproduced image data.
    Type: Grant
    Filed: June 13, 2003
    Date of Patent: April 25, 2006
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Jun Someya, Noritaka Okuda, Masaki Yamakawa, Kyoichiro Oda
  • Patent number: 6937287
    Abstract: In order to reduce the total capacity of a ROM used for adjustment of the black level and the white level of a digitized luminance signal for a television receiver, for example, a comparator compares the input luminance signal with a predetermined threshold value, a NOT gate inverts the input luminance signal, a first switching unit selects the input luminance signal or the output of the NOT gate, a ROM outputs an adjustment characteristic signal responsive to the output of the first switching unit, a multiplier multiplies the output of the ROM by a weighting signal and outputs the result of the multiplication as an adjustment value, a subtractor subtracts the adjustment value from the input luminance signal, an adder adds the adjustment value to the input luminance signal, and a second switching unit selects the output of the subtractor or the output of the adder.
    Type: Grant
    Filed: March 26, 2002
    Date of Patent: August 30, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Toshihiro Gai, Yoshiaki Okuno, Jun Someya, Masaki Yamakawa
  • Patent number: 6931064
    Abstract: In the motion picture data converter, an MPEG-2 decoding unit decodes motion picture data in an MPEG-2 format into motion picture data in an non-compressed format, a motion vector extraction unit extracts motion vector information from the motion picture data being decoded in said MPEG-2 decoding unit, a motion compensation unit generates the motion vector information in the MPEG-4 format, by causing the extracted motion vector information to be reflected in the motion compensation processing for the MPEG-4 format, and executes the motion compensation processing based on the motion vector information, and an MPEG-4 encoding unit encodes motion picture data in the MPEG-4 format, using the motion compensation processed data and the motion picture data in the non-compressed format.
    Type: Grant
    Filed: February 11, 2002
    Date of Patent: August 16, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Masashi Mori, Kunio Nakaoka, Hiroaki Sakai, Yoshinari Sugegaya, Akihiko Naito, Masaki Yamakawa
  • Publication number: 20050156944
    Abstract: A method of changing edge sharpness of an input image being formed from input pixels having intensity levels, the method including detecting pixel-to-pixel variations in the intensity levels in at least one direction in the input image, thereby generating local pixel variation patterns; determining a localized zoom ratio based on the local pixel variation patterns; controlling edge sharpness by changing the localized zoom ratio setting interpolation points with spacing between the interpolation points varying based on the localized zoom ratio and a basic zoom ratio; and generating output pixels from the input pixel by interpolation at the interpolating points.
    Type: Application
    Filed: December 17, 2004
    Publication date: July 21, 2005
    Applicant: Mitsubishi Denki Kabushika Kaisha
    Inventors: Jun Someya, Masaki Yamakawa, Yoshiaki Okuno, Hideki Yoshii
  • Publication number: 20040217930
    Abstract: A liquid-crystal driving circuit has an image data processor that, for example, encodes the present image, decodes the encoded image, delays the encoded image by one frame interval, decodes the delayed encoded image, and uses the two decoded images to generate compensation data for adjusting the gray-scale values in the present image. The encoding process reduces the amount of image data, thereby reducing the size of the frame memory needed to delay the image. The compensation data preferably cause the liquid crystal to reach transmissivity values corresponding to the gray-scale values of the present image within substantially one frame interval. This enables the response speed of the liquid crystal to be controlled accurately.
    Type: Application
    Filed: January 21, 2004
    Publication date: November 4, 2004
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Jun Someya, Masaki Yamakawa
  • Publication number: 20040160617
    Abstract: A correction data output device according to the invention includes correction data outputting means for outputting correction data that corrects object frame data included in an inputted image signal on the basis of the mentioned object frame data and previous frame data, which are one frame period previous to the object frame data, and correction data correcting means for correcting correction data that corrects and outputs the correction data outputted from the mentioned correction data outputting means on the basis of the mentioned object frame data and the mentioned previous frame data.
    Type: Application
    Filed: October 3, 2003
    Publication date: August 19, 2004
    Inventors: Noritaka Okuda, Jun Someya, Masaki Yamakawa
  • Publication number: 20040145596
    Abstract: In the case where an input signal is an interlace signal such as NTSC signal, a flicker interference as aliasing interference brought about by the sampling theorem is contained in a region where a vertical frequency component is high. Accordingly, in the conventional processing in which rate of change in gradation is improved by making a drive voltage of liquid crystal at the time of change in gradation larger than normal liquid crystal drive voltage to increase response rate of the liquid crystal panel, interference component is also emphasized. As a result, quality level of a video picture to be displayed on the liquid crystal panel is deteriorated. The invention provides a compensation device capable of improving rate-of-change in gradation at a part where there is no flicker interference and changing rate-of-change in gradation to suppress the flicker at a part where there is any flicker interference.
    Type: Application
    Filed: October 1, 2003
    Publication date: July 29, 2004
    Inventors: Masaki Yamakawa, Hideki Yoshii, Noritaka Okuda, Jun Someya
  • Publication number: 20040135798
    Abstract: An image is processed by detecting pixel-to-pixel variations in brightness level, generating high spatial frequency information related to the variations, setting interpolation points with a spacing that varies according to the high spatial frequency information, and generating new pixels by interpolation at the interpolation points. By increasing the zoom ratio in one part and reducing the zoom in another part of each edge in a continuous manner, this method can mitigate edge degradation when an image is enlarged or reduced, without introducing discontinuities or other image artifacts. It also provides a convenient way to adjust edge sharpness in an image.
    Type: Application
    Filed: November 20, 2003
    Publication date: July 15, 2004
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Jun Someya, Masaki Yamakawa, Yoshiaki Okuno, Hideki Yoshii