公开(公告)号：US10448013B2

公开(公告)日：2019-10-15

申请号：US15387690

申请日：2016-12-22

Applicant: GOOGLE INC.

Inventor： Debargha Mukherjee ,  Yaowu Xu ,  James Bankoski ,  Paul Wilkins ,  Jingning Han ,  Yuxin Liu ,  Wei-Ting Lin

IPC: H04N19/117 ,  H04N19/105 ,  H04N19/56 ,  H04N19/134 ,  H04N19/137

Abstract: Encoding or decoding blocks of video frames using multiple reference frames with adaptive temporal filtering can include generating one or more candidate reference frames by applying temporal filtering to one or more frames of a video sequence according to relationships between respective ones of the one or more frames and a current frame of the video sequence. A reference frame to use for predicting the current frame can be selected from the one or more candidate reference frames, and a prediction block can be generated using the selected reference frame. During an encoding operation, the prediction block can be used to encode a block of a current frame of the video sequence. During a decoding operation, the prediction block can be used to decode a block of a current frame of the video sequence.

公开(公告)号：US10440394B2

公开(公告)日：2019-10-08

申请号：US15259189

申请日：2016-09-08

Applicant: GOOGLE INC.

Inventor： Jingning Han ,  Ching-Han Chiang

IPC: H04N7/12 ,  H04N19/129 ,  G06T9/00 ,  H04N19/176 ,  H04N19/13 ,  H04N19/60 ,  H04N19/18 ,  H04N19/91 ,  H04N19/134 ,  H04N19/136 ,  H04N19/192

Abstract: Video coding using a context adaptive scan order for entropy coding may include decoding a current block by identifying a context adaptive scan order for entropy decoding a transform block, which may include identifying non-zero-coefficient probabilities for the transform block such that each location in the transform block corresponds to a respective non-zero-coefficient probability from the non-zero-coefficient probabilities, assigning a respective context adaptive scan order position to each location in the transform block in descending magnitude order of the respective corresponding non-zero-coefficient probabilities such that the context adaptive scan order position for each location exceeds the context adaptive scan order position assigned to entropy coding context locations for the respective location, entropy decoding transform coefficients from the encoded video stream based on the context adaptive scan order, and reconstructing the decoded block based on the transform block.

公开(公告)号：US20190089969A1

公开(公告)日：2019-03-21

申请号：US15706735

申请日：2017-09-17

Applicant: GOOGLE INC.

Inventor： Jingning Han ,  Yaowu Xu

IPC: H04N19/436 ,  H04N19/176 ,  H04N19/117 ,  H04N19/86

Abstract: Video coding using dual deblocking filter thresholds may include generating a reconstructed frame by decoding an encoded bitstream and outputting the reconstructed frame. Decoding may include generating a decoded block by decoding a portion of the encoded bitstream, identifying a first deblocking threshold index from the encoded bitstream, identifying a second deblocking threshold index from the encoded bitstream, generating a reconstructed block based on the decoded block, and including the reconstructed block in the reconstructed frame. Generating the reconstructed block may include deblocking based on the first deblocking threshold index and the second deblocking threshold index.

公开(公告)号：US10142628B1

公开(公告)日：2018-11-27

申请号：US15373590

申请日：2016-12-09

Applicant: GOOGLE INC.

Inventor： Debargha Mukherjee ,  Jingning Han

IPC: H04N19/61 ,  H04N19/11 ,  H04N19/159 ,  H04N19/129 ,  H04N19/122 ,  H04N19/625 ,  H04N19/176 ,  H04N19/172

Abstract: Decoding an encoded video stream may include identifying an encoded block identifying an intra prediction mode for decoding the encoded block from the encoded video stream, identifying a transform mode from a plurality of transform modes for decoding the encoded block based on the intra prediction mode, identifying a probability model from a plurality of probability models for decoding the encoded block based on the transform mode, identifying a scan mode for decoding the encoded block based on the transform mode, generating a decoded block by decoding the encoded block using the scan mode, the probability model, the transform mode, and the intra prediction mode, and outputting or storing the decoded block.

公开(公告)号：US20180249179A1

公开(公告)日：2018-08-30

申请号：US15630071

申请日：2017-06-22

Applicant: GOOGLE INC.

Inventor： Jingning Han ,  Yaowu Xu ,  Ching-Han Chiang

IPC: H04N19/60 ,  G06N7/00

Abstract: Transform kernel candidates including a vertical transform type associated with a vertical motion and a horizontal transform type associated with a horizontal motion can be encoded or decoded. During an encoding operation, a residual block of a current block is transformed according to a selected transform kernel candidate to produce a transform block. A probability model for encoding the selected transform kernel candidate is then identified based on neighbor transform blocks of the transform block. The selected transform kernel candidate is then encoded according to the probability model. During a decoding operation, the encoded transform kernel candidate is decoded using the probability model. The encoded transform block is then decoded by inverse transforming dequantized transform coefficients thereof according to the decoded transform kernel candidate.

公开(公告)号：US20180205947A1

公开(公告)日：2018-07-19

申请号：US15409862

申请日：2017-01-19

Applicant: GOOGLE INC.

Inventor： Yaowu Xu ,  Jingning Han ,  Ching-Han Chiang

IPC: H04N19/105 ,  H04N19/167 ,  H04N19/18

CPC classification number: H04N19/105 ,  H04N19/13 ,  H04N19/167 ,  H04N19/18 ,  H04N19/91

Abstract: A sign value of a DC coefficient of a current block is determined using neighbor blocks of the current block. First and second sign values are identified as respectively corresponding to an above neighbor block of the current block and a left neighbor block of the current block. A context value is calculated by applying a first weighting value to the first sign value and a second weighting value to the second sign value. The first weighting value is based on a boundary between the above neighbor block and the current block, and the second weighting value is based on a boundary between the left neighbor block and the current block. A probability value is selected based on the context value. The sign value of the DC coefficient of the current block is then determined using the probability model.

公开(公告)号：US20180184086A1

公开(公告)日：2018-06-28

申请号：US15387690

申请日：2016-12-22

Applicant: GOOGLE INC.

Inventor： Debargha Mukherjee ,  Yaowu Xu ,  James Bankoski ,  Paul Wilkins ,  Jingning Han ,  Yuxin Liu ,  Wei-Ting Lin

IPC: H04N19/117 ,  H04N19/105 ,  H04N19/56

CPC classification number: H04N19/117 ,  H04N19/105 ,  H04N19/134 ,  H04N19/137 ,  H04N19/56

Abstract: Encoding or decoding blocks of video frames using multiple reference frames with adaptive temporal filtering can include generating one or more candidate reference frames by applying temporal filtering to one or more frames of a video sequence according to relationships between respective ones of the one or more frames and a current frame of the video sequence. A reference frame to use for predicting the current frame can be selected from the one or more candidate reference frames, and a prediction block can be generated using the selected reference frame. During an encoding operation, the prediction block can be used to encode a block of a current frame of the video sequence. During a decoding operation, the prediction block can be used to decode a block of a current frame of the video sequence.

公开(公告)号：US09807423B1

公开(公告)日：2017-10-31

申请号：US14950024

申请日：2015-11-24

Applicant: Google Inc.

Inventor： Jingning Han ,  Yaowu Xu ,  Cheng Chen

IPC: H04N19/62 ,  H04N19/14 ,  H04N19/625 ,  H04N19/61 ,  H04N19/176 ,  H04N19/103 ,  H04N19/147 ,  H04N19/159

CPC classification number: H04N19/625 ,  H04N19/103 ,  H04N19/12 ,  H04N19/147 ,  H04N19/159 ,  H04N19/176 ,  H04N19/61

Abstract: Blocks of a frame are encoded by selected according to a hybrid symmetrical discrete sine transform scheme. For a residual block resulting from inter prediction, the residual block is respectively transformed using a discrete cosine transform (DCT) and a symmetrical discrete sine transform (SDST). A first rate-distortion value for encoding the residual block using the DCT and a second rate-distortion value for encoding the residual block using the SDST are generated. For a residual block generated by intra prediction, the residual block is respectively transformed using at least one transform mode, each of which is not the SDST. Multiple inter prediction and intra prediction modes may be considered to encode the current block. The transform mode and the prediction mode resulting in a lowest rate-distortion value for encoding the current block are selected, and the current block is encoded into an encoded bitstream using the selected modes.

公开(公告)号：US20170302950A1

公开(公告)日：2017-10-19

申请号：US15099853

申请日：2016-04-15

Applicant: GOOGLE INC.

Inventor： Yaowu Xu ,  Jingning Han

IPC: H04N19/513 ,  H04L29/06 ,  H04N19/44

CPC classification number: H04N19/513 ,  H04L65/607 ,  H04N19/117 ,  H04N19/159 ,  H04N19/176 ,  H04N19/44 ,  H04N19/463 ,  H04N19/52 ,  H04N19/523 ,  H04N19/82

Abstract: Decoding a video stream may include decoding a first block of a current frame by decoding a first motion vector from the encoded video stream, decoding an identifier of a first interpolation filter from the encoded video stream, and reconstructing the first block using the first motion vector and the first interpolation filter. Decoding a second block of the current frame may include identifying the first motion vector from the first block as a selected motion vector for predicting the second block in response to decoding an inter-prediction mode identifier for decoding the second block, identifying the first interpolation filter as a selected interpolation filter for predicting the second block in response to identifying the first motion vector from the first block as the selected motion vector for predicting the second block, and reconstructing the second block using the first motion vector and the first interpolation filter.

公开(公告)号：US09681128B1

公开(公告)日：2017-06-13

申请号：US13755108

申请日：2013-01-31

Applicant: Google Inc.

Inventor： Jingning Han ,  Debargha Mukherjee

IPC: H04N19/50

CPC classification number: H04N19/00569 ,  H04N19/122 ,  H04N19/129 ,  H04N19/147 ,  H04N19/157 ,  H04N19/176 ,  H04N19/182

Abstract: Blocks of a frame of a video stream can be encoded using directional intra prediction modes followed by transforming the residual blocks. Coding efficiency can be improved by re-aligning pixels of a residual block before transformation to align the pixels of the block with the direction in which the prediction block for the original block was formed. Such an alignment can reduce the number of bits to be included in an encoded bitstream while maintaining the visual quality of the video stream by reducing the amount of structure or texture in the residual block that is not aligned with a horizontal or vertical axis.