Patents Assigned to Nippon Hoso Kyokai
  • Patent number: 11736728
    Abstract: An encoding device 1 includes: a transformer 13 configured to calculate an orthogonal transform coefficient by performing an orthogonal transformation process on a residual image indicating a difference between the input image and a predicted image of the input image; a quantizer 14 configured to generate quantization coefficient by quantizing the orthogonal transform coefficient based on a quantization parameter; an entropy encoder 24 configured to generate encoded data by encoding the quantization coefficient; an image decoder 10 configured to restore an orthogonal transform coefficient from the quantization coefficient based on the quantization parameter and generate a pre-filtering image by adding the predicted image to a residual image restored by performing inverse orthogonal transformation on the orthogonal transform coefficient; and a deblocking filter 18 configured to perform a filtering process on the pre-filtering image and control a filtering strength depending on a result of comparison between a
    Type: Grant
    Filed: August 23, 2022
    Date of Patent: August 22, 2023
    Assignee: NIPPON HOSO KYOKAI
    Inventors: Atsuro Ichigaya, Shunsuke Iwamura, Shimpei Nemoto, Kazuhisa Iguchi
  • Patent number: 11736689
    Abstract: An encoding device 1 includes: a transformation unit 13 configured to calculate an orthogonal transform coefficient by performing an orthogonal transformation process on a residual image indicating a difference between the input image and a predicted image of the input image; a quantization unit 14 configured to generate a quantization coefficient by quantizing the orthogonal transform coefficient on the basis of a quantization parameter; an entropy encoding unit 24 configured to generate encoded data by encoding the quantization coefficient; an image decoding unit 10 configured to restore an orthogonal transform coefficient from the quantization coefficient on the basis of the quantization parameter and generate a reconstructed image by adding the predicted image to a residual image restored by performing inverse orthogonal transformation on the orthogonal transform coefficient; and a deblocking filtering unit 18 configured to perform a filtering process on the reconstructed image, wherein the deblocking fil
    Type: Grant
    Filed: December 1, 2021
    Date of Patent: August 22, 2023
    Assignee: NIPPON HOSO KYOKAI
    Inventors: Atsuro Ichigaya, Shunsuke Iwamura
  • Publication number: 20230262233
    Abstract: An intra predictor (181) for performing intra prediction on each of blocks obtained by dividing an original image in the form of a frame, the intra predictor (181) includes; a linear model calculator (1811a) configured to calculate a linear model of the luminance component and the chroma component of the target block using decoded pixel values of the luminance component and decoded pixel values of the chroma component around the target block on which the intra prediction is performed; a chroma component predictor (1811b) configured to predict pixel values of the chroma component of the target block by applying the linear model calculated by the linear model calculator (1811a) to decoded pixel values of a luminance component of the target block; and a chroma component corrector (1812) configured to correct predicted pixel values of the chroma component obtained by the chroma component predictor (1811b) using decoded pixel values that were not used to calculate a linear model by the linear model calculator (181
    Type: Application
    Filed: March 29, 2023
    Publication date: August 17, 2023
    Applicant: NIPPON HOSO KYOKAI
    Inventors: Shunsuke IWAMURA, Atsuro ICHIGAYA, Shimpei NEMOTO
  • Publication number: 20230247220
    Abstract: An image encoding device encodes a block-based target image. The image encoding device comprises, in a transform skip mode in which orthogonal transform processing of the target image is skipped, a motion compensation predictor configured to generate a prediction image corresponding to the target image by performing motion compensation prediction using a plurality of reference images, an evaluator configured to evaluate a degree of similarity between the plurality of reference images on a pixel-by-pixel basis, a subtractor configured to calculate prediction residuals each indicating a difference between the target image and the prediction image on a pixel-by-pixel basis, a rearranger configured to rearrange the prediction residuals based on a result of evaluation by the evaluator and an encoder configured to encode the prediction residuals rearranged by the rearranger.
    Type: Application
    Filed: March 29, 2023
    Publication date: August 3, 2023
    Applicant: NIPPON HOSO KYOKAI
    Inventors: Shunsuke IWAMURA, Atsuro ICHIGAYA, Shimpei NEMOTO
  • Publication number: 20230239475
    Abstract: An image coding device is provided with a determination unit which determines whether to apply an orthogonal transform to a transform block obtained by dividing a prediction difference signal indicating a difference between an input image and a predicted image or perform a transform skip by which the orthogonal transform is not applied, and an orthogonal transform unit which performs processing selected on the basis of the determination, the image coding device comprising a quantization unit which, when the transform skip is selected on the basis of the determination, quantizes the transform block using a first quantization matrix in which the quantization roughnesses of all elements previously shared with a decoding side are equal, and when the orthogonal transform is applied to the transform block on the basis of the determination, quantizes the transform block using the first quantization matrix or a second quantization matrix that is transmitted to the decoding side.
    Type: Application
    Filed: March 30, 2023
    Publication date: July 27, 2023
    Applicant: NIPPON HOSO KYOKAI
    Inventors: Atsuro ICHIGAYA, Shunsuke IWAMURA, Yasuko MORITA, Shinichi SAKAIDA
  • Publication number: 20230239514
    Abstract: An encoding device comprises: a transformer/quantizer configured to perform a transform process and a quantization process on a residual signal that represents a difference between an encoding-target block and a prediction block obtained by predicting the encoding-target block; an inverse quantizer/inverse transformer configured to restore the residual signal by performing an inverse quantization process and an inverse transform process on transform coefficients obtained by the transformer/quantizer; a combiner configured to reconstruct the encoding-target block by combining the restored residual signal and the prediction block; a deblocking filter configured to perform a filter process on a boundary between two blocks including the reconstructed block and a block adjacent to the reconstructed block; and a filter controller configured to control the deblocking filter, based on a type of the transform process applied with respect to the two blocks.
    Type: Application
    Filed: March 29, 2023
    Publication date: July 27, 2023
    Applicant: NIPPON HOSO KYOKAI
    Inventors: Shunsuke IWAMURA, Atsuro ICHIGAYA, Shimpei NEMOTO
  • Publication number: 20230239473
    Abstract: An encoding device encodes each encoding-target block.
    Type: Application
    Filed: March 29, 2023
    Publication date: July 27, 2023
    Applicant: NIPPON HOSO KYOKAI
    Inventors: Shunsuke IWAMURA, Shimpei NEMOTO, Atsuro ICHIGAYA
  • Patent number: 11695955
    Abstract: An image encoding device (1) includes the cross-component intra predictor (171a) generates a predicted chroma block through cross-component intra prediction in which a chroma block to be encoded is predicted by referring to, as the neighbouring decoded pixels adjacent to the chroma block, decoded luminance pixels and decoded chroma pixels, a candidate generator (181) configured to generate candidates for an orthogonal transform type to be applied to orthogonal transform processing on prediction residuals that represent errors between the predicted chroma block and the chroma block; and a transformer (121) configured to perform the orthogonal transform processing on the chroma prediction residuals by using an orthogonal transform type selected from among the candidates generated by the candidate generator (181).
    Type: Grant
    Filed: June 10, 2022
    Date of Patent: July 4, 2023
    Assignee: NIPPON HOSO KYOKAI
    Inventors: Shunsuke Iwamura, Atsuro Ichigaya, Shimpei Nemoto
  • Publication number: 20230199215
    Abstract: A prediction image correcting device comprises a predictor (108) configured to predict a target image block obtained by dividing a present image frame by using a plurality of reference images to generate a prediction image corresponding to the target image block a prediction accuracy evaluator (109) configured to evaluate prediction accuracy of the prediction image based on a degree of similarity between the plurality of reference images used for generating the prediction image and a corrector (110) configured to perform correction processing on the prediction image by using a decoded neighboring block adjacent to the target image block, wherein the corrector is configured to control the correction processing based at least on an evaluation result of the prediction accuracy evaluator.
    Type: Application
    Filed: February 22, 2023
    Publication date: June 22, 2023
    Applicant: NIPPON HOSO KYOKAI
    Inventors: Shunsuke Iwamura, Atsuro Ichigaya, Shimpei Nemoto
  • Patent number: 11677965
    Abstract: A method includes: decoding a bitstream and thereby outputting a transform coefficients for each color component of the block, a first flag indicating for each color component whether the block includes a non-zero transform coefficient, and a second flag indicating whether the block has been encoded using a color space transform that transforming a color space of a prediction residual from a color space of the original image to another color space; performing a color space inverse transform for the prediction residual restored from the transform coefficients, when the second flag indicates that the block has been encoded using the color space transform; and determining whether to perform chroma residual scaling for the prediction residual of the chrominance component, based on the first flag of a chrominance component and the second flag, the chroma residual scaling that performs scaling based on a luminance component corresponding to the chrominance component.
    Type: Grant
    Filed: March 22, 2022
    Date of Patent: June 13, 2023
    Assignee: NIPPON HOSO KYOKAI
    Inventors: Shunsuke Iwamura, Shimpei Nemoto, Atsuro Ichigaya
  • Publication number: 20230179765
    Abstract: A deblocking filter control device that controls a deblocking filter process performed on a decoded image includes: a parameter deriver configured to derive a parameter value that controls a filter strength in the deblocking filter process; and a parameter transformer configured to output a transformed parameter value by transforming the parameter value based on an input bit depth that is a bit depth of the video signal, wherein when the input bit depth is smaller than a predetermined bit depth, the parameter transformer is configured to output the transformed parameter value by adding an offset value to the parameter value and making a bit shift of a result of the addition, and the parameter transformer is configured to change the offset value based on the input bit depth.
    Type: Application
    Filed: January 27, 2023
    Publication date: June 8, 2023
    Applicant: NIPPON HOSO KYOKAI
    Inventors: Shunsuke IWAMURA, Shimpei NEMOTO, Atsuro ICHIGAYA
  • Patent number: 11647191
    Abstract: An encoding device encodes each encoding-target block.
    Type: Grant
    Filed: March 21, 2022
    Date of Patent: May 9, 2023
    Assignee: NIPPON HOSO KYOKAI
    Inventors: Shunsuke Iwamura, Shimpei Nemoto, Atsuro Ichigaya
  • Patent number: 11647206
    Abstract: An intra predictor (181) for performing intra prediction on each of blocks obtained by dividing an original image in the form of a frame, the intra predictor (181) includes; a linear model calculator (1811a) configured to calculate a linear model of the luminance component and the chroma component of the target block using decoded pixel values of the luminance component and decoded pixel values of the chroma component around the target block on which the intra prediction is performed; a chroma component predictor (1811b) configured to predict pixel values of the chroma component of the target block by applying the linear model calculated by the linear model calculator (1811a) to decoded pixel values of a luminance component of the target block; and a chroma component corrector (1812) configured to correct predicted pixel values of the chroma component obtained by the chroma component predictor (1811b) using decoded pixel values that were not used to calculate a linear model by the linear model calculator (181
    Type: Grant
    Filed: February 12, 2021
    Date of Patent: May 9, 2023
    Assignee: NIPPON HOSO KYOKAI
    Inventors: Shunsuke Iwamura, Atsuro Ichigaya, Shimpei Nemoto
  • Patent number: 11647195
    Abstract: An image coding device is provided with a determination unit which determines whether to apply an orthogonal transform to a transform block obtained by dividing a prediction difference signal indicating a difference between an input image and a predicted image or perform a transform skip by which the orthogonal transform is not applied, and an orthogonal transform unit which performs processing selected on the basis of the determination, the image coding device comprising a quantization unit which, when the transform skip is selected on the basis of the determination, quantizes the transform block using a first quantization matrix in which the quantization roughnesses of all elements previously shared with a decoding side are equal, and when the orthogonal transform is applied to the transform block on the basis of the determination, quantizes the transform block using the first quantization matrix or a second quantization matrix that is transmitted to the decoding side.
    Type: Grant
    Filed: January 3, 2022
    Date of Patent: May 9, 2023
    Assignee: NIPPON HOSO KYOKAI
    Inventors: Atsuro Ichigaya, Shunsuke Iwamura, Yasuko Morita, Shinichi Sakaida
  • Patent number: 11647233
    Abstract: An encoding device comprises: a transformer/quantizer configured to perform a transform process and a quantization process on a residual signal that represents a difference between an encoding-target block and a prediction block obtained by predicting the encoding-target block; an inverse quantizer/inverse transformer configured to restore the residual signal by performing an inverse quantization process and an inverse transform process on transform coefficients obtained by the transformer/quantizer; a combiner configured to reconstruct the encoding-target block by combining the restored residual signal and the prediction block; a deblocking filter configured to perform a filter process on a boundary between two blocks including the reconstructed block and a block adjacent to the reconstructed block; and a filter controller configured to control the deblocking filter, based on a type of the transform process applied with respect to the two blocks.
    Type: Grant
    Filed: December 23, 2021
    Date of Patent: May 9, 2023
    Assignee: NIPPON HOSO KYOKAI
    Inventors: Shunsuke Iwamura, Atsuro Ichigaya, Shimpei Nemoto
  • Patent number: 11647224
    Abstract: An image encoding device encodes a block-based target image. The image encoding device comprises, in a transform skip mode in which orthogonal transform processing of the target image is skipped, a motion compensation predictor configured to generate a prediction image corresponding to the target image by performing motion compensation prediction using a plurality of reference images, an evaluator configured to evaluate a degree of similarity between the plurality of reference images on a pixel-by-pixel basis, a subtractor configured to calculate prediction residuals each indicating a difference between the target image and the prediction image on a pixel-by-pixel basis, a rearranger configured to rearrange the prediction residuals based on a result of evaluation by the evaluator and an encoder configured to encode the prediction residuals rearranged by the rearranger.
    Type: Grant
    Filed: January 31, 2022
    Date of Patent: May 9, 2023
    Assignee: NIPPON HOSO KYOKAI
    Inventors: Shunsuke Iwamura, Atsuro Ichigaya, Shimpei Nemoto
  • Patent number: 11622127
    Abstract: A prediction image correcting device comprises a predictor (108) configured to predict a target image block obtained by dividing a present image frame by using a plurality of reference images to generate a prediction image corresponding to the target image block a prediction accuracy evaluator (109) configured to evaluate prediction accuracy of the prediction image based on a degree of similarity between the plurality of reference images used for generating the prediction image and a corrector (110) configured to perform correction processing on the prediction image by using a decoded neighboring block adjacent to the target image block, wherein the corrector is configured to control the correction processing based at least on an evaluation result of the prediction accuracy evaluator.
    Type: Grant
    Filed: October 2, 2020
    Date of Patent: April 4, 2023
    Assignee: NIPPON HOSO KYOKAI
    Inventors: Shunsuke Iwamura, Atsuro Ichigaya, Shimpei Nemoto
  • Patent number: 11595645
    Abstract: A deblocking filter control device that controls a deblocking filter process performed on a decoded image includes: a parameter deriver configured to derive a parameter value that controls a filter strength in the deblocking filter process; and a parameter transformer configured to output a transformed parameter value by transforming the parameter value based on an input bit depth that is a bit depth of the video signal, wherein when the input bit depth is smaller than a predetermined bit depth, the parameter transformer is configured to output the transformed parameter value by adding an offset value to the parameter value and making a bit shift of a result of the addition, and the parameter transformer is configured to change the offset value based on the input bit depth.
    Type: Grant
    Filed: March 21, 2022
    Date of Patent: February 28, 2023
    Assignee: NIPPON HOSO KYOKAI
    Inventors: Shunsuke Iwamura, Shimpei Nemoto, Atsuro Ichigaya
  • Publication number: 20230040392
    Abstract: A transmitting device (30, 30a) is configured to transmit, to a receiving device (40, 40a), a plurality of video signals captured from different positions, the plurality of video signals being grouped by a plurality of groups depending on imaging positions at which the video signals are captured. The transmitting device (30, 30a) comprises: a controller (32) configured to assign an ID for identifying each of the plurality of groups; and a communication interface (37) configured to transmit a video signal to which the ID is assigned, to the receiving device (40, 40a).
    Type: Application
    Filed: December 25, 2020
    Publication date: February 9, 2023
    Applicant: NIPPON HOSO KYOKAI
    Inventor: Shuichi AOKI
  • Publication number: 20230040274
    Abstract: An encoding device encodes each encoding-target block.
    Type: Application
    Filed: October 6, 2022
    Publication date: February 9, 2023
    Applicant: NIPPON HOSO KYOKAI
    Inventors: Shunsuke IWAMURA, Shimpei NEMOTO, Atsuro ICHIGAYA