Patents by Inventor Kazuto Kamikura

Kazuto Kamikura 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: 9386322
    Abstract: A scalable video encoding method of performing encoding by predicting an upper-layer signal having a relatively high spatial resolution by means of interpolation using an immediately-lower-layer signal having a relatively low spatial resolution. The method computes a first weighting coefficient for each image area of a predetermined unit size in a search for estimating a motion between an encoding target image area in an upper layer and a reference image area, where the first weighting coefficient is computed based on a brightness variation between an image area, which belongs to an immediately-lower layer and has the same spatial position as the encoding target image area, and the reference image area; and performs a motion estimation using a signal which is obtained by correcting a decoded signal of the reference image area by the first weighting coefficient and functions as an estimated signal in the motion estimation, so as to compute a motion vector.
    Type: Grant
    Filed: July 1, 2008
    Date of Patent: July 5, 2016
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Kazuya Hayase, Yukihiro Bandoh, Seishi Takamura, Kazuto Kamikura, Yoshiyuki Yashima
  • Patent number: 9154789
    Abstract: A motion vector predictive encoding method, a motion vector decoding method, a predictive encoding apparatus, a decoding apparatuses, and storage media storing motion vector predictive encoding and decoding programs are provided, thereby reducing the amount of generated code with respect to the motion vector, and improving the efficiency of the motion-vector prediction. If the motion-compensating mode of the target small block to be encoded is the global motion compensation, the encoding mode of an already-encoded small block is the interframe coding mode, and the motion-compensating mode of the already-encoded small block is the global motion compensation, then the motion vector of the translational motion model is determined for each pixel of the already-encoded small block, based on the global motion vector (steps S1-S5). Next, the representative motion vector is calculated as the predicted vector, based on the motion vector of each pixel of the already-encoded small block (step S6).
    Type: Grant
    Filed: January 10, 2013
    Date of Patent: October 6, 2015
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Atsushi Shimizu, Hirohisa Jozawa, Kazuto Kamikura, Hiroshi Watanabe, Atsushi Sagata, Seishi Takamura
  • Patent number: 9088802
    Abstract: A video encoding method for encoding a plurality of images as a video image. The method includes a reference parallax data setting step of setting reference parallax data which indicates a viewing difference between a first image and an already-encoded second image, in order to encode target encoding data assigned to a predetermined position in the first image; a corresponding position setting step of setting a corresponding position in the second image, which can correspond to the predetermined position, by using the reference parallax data; a code table setting step of setting a code table corresponding to target encoding data assigned to the corresponding position; and a target encoding data encoding step of encoding the target encoding data in the first image by using the code table.
    Type: Grant
    Filed: December 28, 2005
    Date of Patent: July 21, 2015
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Masaki Kitahara, Kazuto Kamikura, Yoshiyuki Yashima
  • Patent number: 9066096
    Abstract: A video encoding method for generating, based on disparity information between an already-encoded reference camera image and an encoding target camera image corresponding to the reference camera image, a disparity-compensated image by means of inter-camera image prediction; and encoding a differential image between the encoding target camera image and the disparity-compensated image. The method includes selecting, for each predetermined section unit on the differential image, one of a decoded differential image group obtained by decoding a differential image between the already-encoded camera image and the disparity-compensated image and a decoded camera image group obtained by decoding the already-encoded camera image, by determining whether or not there is a disparity-compensated image at the corresponding position, that is, whether or not the corresponding pixel in the disparity-compensated image has an effective value.
    Type: Grant
    Filed: December 26, 2007
    Date of Patent: June 23, 2015
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Shinya Shimizu, Masaki Kitahara, Kazuto Kamikura, Yoshiyuki Yashima
  • Patent number: 9055303
    Abstract: A video encoding method, in which a video signal consisting of two or more signal elements is targeted to be encoded, includes a step of setting a downsampling ratio is set for a specific signal element in a frame, in accordance with the characteristics in the frame; and a step of generating a target video signal to be encoded, by subjecting the specific signal element in the frame to downsampling in accordance with the set downsampling ratio. The frame may be divided into partial areas in accordance with localized characteristics in the frame; and a downsampling ratio for a specific signal element in these partial areas may be set in accordance with the characteristics in each partial area.
    Type: Grant
    Filed: October 5, 2007
    Date of Patent: June 9, 2015
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Yukihiro Bandoh, Kazuto Kamikura, Yoshiyuki Yashima
  • Patent number: 9008173
    Abstract: A method for encoding an image using an intraframe prediction is provided which includes selecting a gradient of a pixel value that is indicated by an image signal to be predicted among a plurality of gradient candidates, generating a predicted signal by applying a gradient in accordance with the distance from a prediction reference pixel based on the gradient, intraframe-encoding the image signal to be predicted based on the predicted signal, and encoding information indicating the size of the selected gradient. Alternatively, the method includes estimating the gradient of a pixel value that is indicated by an image signal to be predicted based on an image signal which has already been encoded, generating a predicted signal by applying a gradient in accordance with the distance from a prediction reference pixel based on the gradient, and intraframe-encoding the image signal to be predicted based on the predicted signal.
    Type: Grant
    Filed: October 14, 2008
    Date of Patent: April 14, 2015
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Shohei Matsuo, Seishi Takamura, Kazuto Kamikura, Yoshiyuki Yashima
  • Patent number: 8675735
    Abstract: When video images are processed by applying temporal or spatial interframe prediction encoding to each divided area, and generating a predicted image of a processing target area based on a reference frame of the processing target area and reference information which indicates a predicted target position of the processing target area in the reference frame, predicted reference information is generated as predicted information of the reference information. Reference information used when an area adjacent to the processing target area was processed is determined as predicted reference information prediction data used for predicting the reference information of the processing target area. Reference area reference information is generated using one or more pieces of reference information used when a reference area indicated by the prediction data was processed. The predicted reference information prediction data is updated using the reference area reference information.
    Type: Grant
    Filed: December 12, 2012
    Date of Patent: March 18, 2014
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Shinya Shimizu, Kazuto Kamikura, Yoshiyuki Yashima, Hideaki Kimata
  • Patent number: 8654854
    Abstract: A video encoding method includes selecting a reference vector target frame and a reference frame from among already-encoded frames; encoding information for designating each frame; setting a reference vector for indicating an area in the reference vector target frame with respect to an encoding target area; encoding the reference vector; performing a corresponding area search by using image information of a reference vector target area, which belongs to the reference vector target frame and is indicated by the reference vector, and the reference frame; determining a reference area in the reference frame based on the search result; generating a predicted image by using image information of the reference frame, which corresponds to the reference area; and encoding differential information between image information of the encoding target area and the predicted image.
    Type: Grant
    Filed: March 15, 2012
    Date of Patent: February 18, 2014
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Shinya Shimizu, Hideaki Kimata, Kazuto Kamikura, Yoshiyuki Yashima
  • Patent number: 8611434
    Abstract: An image processing method includes determining a first bandwidth based on original image data; computing a filter coefficient array for implementing frequency characteristics corresponding to a band limitation using the first bandwidth; generating first filtered image data by subjecting the original image data to a filtering process using the first filter coefficient array; deriving an objective image-quality estimation value of the first filtered image data, and computing an allocation coefficient used for determining an optimum bandwidth, based on the objective image-quality estimation value; determining the optimum bandwidth corresponding to the computed allocation coefficient by referring to a table in which a correspondence relationship between the allocation coefficient and the optimum bandwidth is defined; computing an optimum filter coefficient array for implementing the frequency characteristics corresponding to a band limitation using the optimum bandwidth; and generating optimum filtered image dat
    Type: Grant
    Filed: July 2, 2007
    Date of Patent: December 17, 2013
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Tokinobu Mitasaki, Kazuto Kamikura
  • Patent number: 8548039
    Abstract: In a video scalable encoding method, based on encoding information of an immediately-lower image region in an immediately-lower layer, which is present at spatially the same position as an encoding target image region, a data structure of the weight coefficient, that includes a proportional coefficient and an offset coefficient, is determined. When the immediately-lower image region performed interframe prediction in the immediately-lower layer, the method identifies an immediately-lower layer reference image region that the immediately-lower image region used as a prediction reference for motion prediction, and calculates the weight coefficient by applying a weight coefficient that the immediately-lower image region used in weighted motion prediction to a DC component of an image region in the upper layer, which is present at spatially the same position as the immediately-lower layer reference image region, and assuming a result of the application as a DC component of the immediately-lower image region.
    Type: Grant
    Filed: October 20, 2008
    Date of Patent: October 1, 2013
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Kazuya Hayase, Yukihiro Bandoh, Seishi Takamura, Kazuto Kamikura, Yoshiyuki Yashima
  • Patent number: 8548064
    Abstract: A video encoding method for encoding video images as a single video image by using parallax compensation which performs prediction by using parallax between the video images, and a corresponding decoding method. The number of parameters as parallax data used for the parallax compensation is selected and set for each reference image. Data of the set number of parameters is encoded, and parallax data in accordance with the number of parameters is encoded. During decoding, parallax-parameter number data, which is included in encoded data and designates the number of parameters as parallax data for each reference image, is decoded, and parallax data in accordance with the number of parameters is decoded, where the parallax data is included in the encoded data.
    Type: Grant
    Filed: December 29, 2006
    Date of Patent: October 1, 2013
    Assignees: Nippon Telegraph and Telephone Corporation, National University Corporation Nagoya University
    Inventors: Masaki Kitahara, Hideaki Kimata, Shinya Shimizu, Kazuto Kamikura, Yoshiyuki Yashima, Masayuki Tanimoto, Toshiaki Fujii, Kenji Yamamoto
  • Patent number: 8532190
    Abstract: A video encoding method includes selecting a reference vector target frame and a reference frame from among already-encoded frames; encoding information for designating each frame; setting a reference vector for indicating an area in the reference vector target frame with respect to an encoding target area; encoding the reference vector; performing a corresponding area search by using image information of a reference vector target area, which belongs to the reference vector target frame and is indicated by the reference vector, and the reference frame; determining a reference area in the reference frame based on the search result; generating a predicted image by using image information of the reference frame, which corresponds to the reference area; and encoding differential information between image information of the encoding target area and the predicted image.
    Type: Grant
    Filed: October 24, 2007
    Date of Patent: September 10, 2013
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Shinya Shimizu, Hideaki Kimata, Kazuto Kamikura, Yoshiyuki Yashima
  • Patent number: 8509302
    Abstract: In scalable video encoding, incidence rates of combinations of optimum prediction modes to be selected for spatially corresponding blocks of an upper layer and a lower layer are determined based on an optimum prediction mode that was selected in a conventional encoding, and then a correspondence table that describes relationships therebetween is created. Subsequently, the combinations of the selected optimum prediction modes described in the correspondence table are narrowed down based on the value of the incidence rate so as to create prediction mode correspondence information that describes the combinations of the optimum prediction mode narrowed down.
    Type: Grant
    Filed: October 21, 2009
    Date of Patent: August 13, 2013
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Kazuya Hayase, Yukihiro Bandoh, Seishi Takamura, Kazuto Kamikura, Yoshiyuki Yashima
  • Patent number: 8472522
    Abstract: A video encoding method includes setting candidates for reference pixels to pixels within a predetermined distance range measured from an encoding target block; generating a predicted signal by sequentially selecting reference pixels used for the intra prediction of the encoding target block from among the reference pixel candidates while changing a distance condition from the encoding target block, and by generating the predicted signal based on the reference pixels for each distance condition; computing an encoding cost required for subjecting the encoding target block to intra prediction encoding using each generated predicted signal; finally determining reference pixels used for the intra prediction of the encoding target block based on each computed encoding cost; and encoding information which indicates the position of the determined reference pixels.
    Type: Grant
    Filed: February 20, 2008
    Date of Patent: June 25, 2013
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Shohei Matsuo, Seishi Takamura, Kazuto Kamikura, Yoshiyuki Yashima
  • Patent number: 8467460
    Abstract: A video processing method includes dividing a processing target image, which forms a video image, into a plurality of divided areas; determining a bandwidth applied to the divided areas; computing a filter coefficient array for implementing frequency characteristics corresponding to a band limitation using the bandwidth; subjecting the image data to a filtering process using the filter coefficient array; deriving a value of error information between the obtained data and the original image data, and computing an allocation coefficient used for determining an optimum bandwidth, based on the derived value; determining, for each divided area, the optimum bandwidth corresponding to the allocation coefficient, and computing an optimum filter coefficient array for implementing the frequency characteristics corresponding to a band limitation using the optimum bandwidth; subjecting the image data of the divided area to a filtering process using the optimum filter coefficient array; and synthesizing the obtained data
    Type: Grant
    Filed: December 26, 2007
    Date of Patent: June 18, 2013
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Tokinobu Mitasaki, Kazuto Kamikura, Naoki Ono
  • Patent number: 8451894
    Abstract: By using parallax compensation which performs prediction by using parallax between video images, the video images are encoded as a single video image. Reference parallax for a target image to be encoded is set, wherein the reference parallax is estimated using a reference image; area division in an image frame is set; parallax displacement for each divided area is set, wherein the parallax displacement is the difference between the reference parallax and parallax for the parallax compensation; data of the area division is encoded; and data for indicating the parallax displacement is encoded. During decoding, reference parallax for a target image to be decoded is set, wherein it is estimated using a reference image; data for indicating area division, which is included in encoded data, is decoded; and data of parallax displacement, which is included in the encoded data, is decoded for each area indicated by the area division data.
    Type: Grant
    Filed: January 4, 2007
    Date of Patent: May 28, 2013
    Assignees: Nippon Telegraph and Telephone Corporation, National University Corporation Nagoya University
    Inventors: Masayuki Tanimoto, Toshiaki Fujii, Kenji Yamamoto, Masaki Kitahara, Hideaki Kimata, Shinya Shimizu, Kazuto Kamikura, Yoshiyuki Yashima
  • Publication number: 20130058584
    Abstract: An image encoding method includes determining corresponding points on an encoding target image, which correspond to pixels on a reference image, based on distance from a camera of the reference image to an object, and positional relationship between cameras; computing a parallax vector from each pixel position to the corresponding point in pixel space; computing a target predictive vector having the same start as the parallax vector and components obtained by rounding off components of the parallax vector; computing a target reference vector having the same start as the parallax vector and the same size and direction as a differential vector between the target predictive vector and the parallax vector; and setting a predicted value of a pixel on the encoding target image, which is indicated by the target predictive vector, to a value of a pixel on the reference image, which is indicated by the target reference vector.
    Type: Application
    Filed: September 12, 2012
    Publication date: March 7, 2013
    Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Shinya SHIMIZU, Masaki KITAHARA, Kazuto KAMIKURA, Yoshiyuki YASHIMA
  • Patent number: 8385628
    Abstract: An image encoding method includes determining and encoding global parallax data which is probably correct parallax data in consideration of the Epipolar geometry constraint between a camera of a standard viewpoint, which is selected from the entire multi-viewpoint images, and images obtained by all the other viewpoints; generating base parallax data for each camera as a viewpoint other than the standard viewpoint, where the base parallax data is probably correct parallax data in consideration of the Epipolar geometry constraint between the image of the relevant camera and the images of all the other cameras based on the global parallax data and the camera parameters; determining and encoding correction parallax data used for correcting the base parallax data, so as to indicate parallax data between the image of the relevant camera and an already-encoded reference viewpoint image used for parallax compensation; and encoding the image of the relevant camera by using parallax data obtained by correcting the base
    Type: Grant
    Filed: September 18, 2007
    Date of Patent: February 26, 2013
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Shinya Shimizu, Masaki Kitahara, Kazuto Kamikura, Yoshiyuki Yashima
  • Patent number: 8363985
    Abstract: An image generation method for generating image information of an image C by using an image A and an image B having a resolution higher than that of image A. Image C having the same resolution as image B is generated by enlarging image A; presence or absence of a point in image B corresponding to each pixel position of image C and the position of the relevant corresponding point are estimated; and to each pixel position in image C for which it is estimated that there is a corresponding point, image information of the corresponding position in image B is assigned. It is possible to generate image information at each pixel position in image C for which it is estimated in the corresponding point estimation that there is no corresponding point, by using the image information assigned according to an estimation result that there is a corresponding point.
    Type: Grant
    Filed: October 9, 2008
    Date of Patent: January 29, 2013
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Hideaki Kimata, Shinya Shimizu, Kazuto Kamikura, Yoshiyuki Yashima
  • Patent number: 8355438
    Abstract: When video images are processed by applying temporal or spatial interframe prediction encoding to each divided area, and generating a predicted image of a processing target area based on a reference frame of the processing target area and reference information which indicates a predicted target position of the processing target area in the reference frame, predicted reference information is generated as predicted information of the reference information. Reference information used when an area adjacent to the processing target area was processed is determined as predicted reference information prediction data used for predicting the reference information of the processing target area. Reference area reference information is generated using one or more pieces of reference information used when a reference area indicated by the prediction data was processed. The predicted reference information prediction data is updated using the reference area reference information.
    Type: Grant
    Filed: October 23, 2007
    Date of Patent: January 15, 2013
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Shinya Shimizu, Kazuto Kamikura, Yoshiyuki Yashima, Hideaki Kimata