公开(公告)号：US11039131B2

公开(公告)日：2021-06-15

申请号：US16831943

申请日：2020-03-27

Applicant: GOOGLE LLC

Inventor： Urvang Joshi ,  Debargha Mukherjee

IPC: H04N19/11 ,  H04N19/593 ,  H04N19/176 ,  H04N19/61 ,  H04N19/59

Abstract: An apparatus for coding a block of a frame using intra-prediction includes a memory and a processor. The processor is configured to execute instructions stored in the memory to obtain an intra-prediction mode for coding the block of the frame; select a transform type for coding a transform block of a residual block, which results from predicting the block using the intra-prediction mode; and code the transform block using the transform type. To select the transform type includes to, in a case where the intra-prediction mode is a SMOOTH_PRED, select a ADST_ADST transform type; in a case where the intra-prediction mode is a SMOOTH_H_PRED, select a DCT_ADST transform type; and in a case where the intra-prediction mode is a SMOOTH_V_PRED, select a ADST_DCT transform type.

公开(公告)号：US10798408B2

公开(公告)日：2020-10-06

申请号：US16407297

申请日：2019-05-09

Applicant: GOOGLE LLC

Inventor： James Bankoski ,  Debargha Mukherjee ,  Yaowu Xu

IPC: H04N19/52 ,  H04N19/105 ,  H04N19/176 ,  H04N19/119 ,  H04N19/513 ,  H04N19/136 ,  H04N19/167 ,  H04N19/44

Abstract: A first partitioning for partitioning a first region of a frame before a current frame in a video sequence is determined. The first partitioning defines at least two prediction sub-regions of the first region, and the prediction sub-regions include contiguous, non-overlapping groups of pixels. A motion vector that predicts a prediction sub-region of the first region is determined. The first partitioning is modified to a second partitioning by moving at least one border of the first partitioning that is between adjacent prediction sub-regions of the first region by the motion vector. A current region of the current frame that is collocated with the first region is partitioned by the second partitioning, and is encoded or decoded. The technique eliminates the need to re-partition an entire frame each time, and can be used with both rectangular-shaped block partitioning and partitioning using masks and other partitioning techniques.

公开(公告)号：US20200228800A1

公开(公告)日：2020-07-16

申请号：US16831943

申请日：2020-03-27

Applicant: GOOGLE LLC

Inventor： Urvang Joshi ,  Debargha Mukherjee

IPC: H04N19/11 ,  H04N19/593 ,  H04N19/176 ,  H04N19/61

Abstract: An apparatus for coding a block of a frame using intra-prediction includes a memory and a processor. The processor is configured to execute instructions stored in the memory to obtain an intra-prediction mode for coding the block of the frame; select a transform type for coding a transform block of a residual block, which results from predicting the block using the intra-prediction mode; and code the transform block using the transform type. To select the transform type includes to, in a case where the intra-prediction mode is a SMOOTH_PRED, select a ADST_ADST transform type; in a case where the intra-prediction mode is a SMOOTH_H_PRED, select a DCT_ADST transform type; and in a case where the intra-prediction mode is a SMOOTH_V_PRED, select a ADST_DCT transform type.

公开(公告)号：US10567793B2

公开(公告)日：2020-02-18

申请号：US15174223

申请日：2016-06-06

Applicant: GOOGLE LLC

Inventor： Debargha Mukherjee ,  Yue Chen

IPC: H04N19/567 ,  H04N19/176 ,  H04N19/119 ,  H04N19/107 ,  H04N19/157 ,  H04N19/182 ,  H04N19/583

Abstract: Encoding frames of a video stream may include encoding a current block of a current frame, generating a base prediction block for the current block based on current prediction parameters associated with the current block, identifying adjacent prediction parameters used for encoding previously encoded adjacent blocks that are adjacent to the current block. At least one side of the current block is adjacent to two or more of the previously encoded adjacent blocks. The encoding may include determining overlap regions in the current block, each of the overlap regions corresponding to a respective previously encoded adjacent block, generating an overlapped prediction of pixel values for each of the overlap regions according to a weighted function of the base prediction and a prediction based on the adjacent prediction parameters. The weighted function may be based on a difference between the current prediction parameters and the adjacent prediction parameters.

公开(公告)号：US20190379889A1

公开(公告)日：2019-12-12

申请号：US16004929

申请日：2018-06-11

Applicant: GOOGLE LLC

Inventor： Urvang Joshi ,  Debargha Mukherjee

IPC: H04N19/122 ,  H04N19/176 ,  H04N19/124 ,  H04N19/18 ,  H04N19/159 ,  H04N19/82

Abstract: Improved transforms are used to encode and decode large video and image blocks. During encoding, a prediction residual block having a large size (e.g., larger than 32x32) is generated. The pixel values of the prediction residual block are transformed to produce transform coefficients. After determining that the transform coefficients exceed a threshold cardinality representative of a maximum transform block size (e.g., 32x32), a number of the transform coefficients are discarded such that a remaining number of transform coefficients does not exceed the threshold cardinality. A transform block is then generated using the remaining number. During decoding, after determining that the transform coefficients exceed the threshold cardinality, a number of new coefficients are added to the transform coefficients such that a total number of transform coefficients exceeds the threshold cardinality. The transform coefficients are then inverse transformed into a prediction residual block having a large size.

公开(公告)号：US10432972B2

公开(公告)日：2019-10-01

申请号：US15297603

申请日：2016-10-19

Applicant: GOOGLE LLC

Inventor： Debargha Mukherjee ,  Yue Chen ,  Aamir Anis

IPC: H04N19/65 ,  H04N19/184 ,  H04N19/172 ,  H04N19/182 ,  H04N19/176 ,  H04N19/46 ,  H04N19/117 ,  H04N19/154 ,  H04N19/174 ,  H04N19/82 ,  H04N19/136

Abstract: Reducing error in a reconstructed frame is described. Pixels of the frame are classified into classes based on a classification scheme. Offset values for each class of at least some of the classes are determined, and a respective offset value for a class is applied to each pixel of the class, resulting in offset-adjusted pixels for the class. For the classes, a respective error rate reduction in using the respective offset value for a class as compared to omitting the respective offset value is determined, where the respective error rate reduction is based on the pixels of the class in the reconstructed frame, the offset-adjusted pixels of the class, and co-located source pixels in a source frame decoded to generate the reconstructed frame. A subset of classes is selected for reducing error in the reconstructed frame based on the error rate reductions.

公开(公告)号：US20190289319A1

公开(公告)日：2019-09-19

申请号：US16434339

申请日：2019-06-07

Applicant: GOOGLE LLC

Inventor： Debargha Mukherjee ,  Yaowu Xu ,  James Bankoski ,  Yuxin Liu

IPC: H04N19/53 ,  H04N19/573 ,  H04N19/109 ,  H04N19/513 ,  H04N19/105 ,  H04N19/11

Abstract: Coding a current block using multi-level compound predictor is disclosed. An apparatus includes a memory and a processor. The processor is configured to execute instructions stored in the memory to generate four or more prediction blocks; combine a first prediction block and a second prediction block of the four or more prediction blocks to form a first first-level compound prediction block; combine a third prediction block and a fourth prediction block of the four or more prediction blocks to form a second first-level compound prediction block; and combine, to obtain a prediction block for coding the current block, the first first-level compound prediction block and the second first-level compound prediction block.

公开(公告)号：US10277897B1

公开(公告)日：2019-04-30

申请号：US15397083

申请日：2017-01-03

Applicant: GOOGLE LLC

Inventor： Debargha Mukherjee ,  Aamir Anis ,  Yue Chen

IPC: H04N7/12 ,  H04N11/02 ,  H04N11/04 ,  H04N19/117 ,  H04N19/172 ,  H04N19/184 ,  H04N19/182

Abstract: Filtering for a reconstructed frame is described. An initial reconstructed frame is determined from an encoded video bitstream, a subset of filter parameters is decoded from the encoded video bitstream for the initial reconstructed frame, a filter set is determined from the subset of filter parameters based on a relationship between the filter set and the subset of filter parameters, and a final reconstructed frame is generated by applying at least one filter from the filter set to the initial reconstructed frame.

公开(公告)号：US20180213239A1

公开(公告)日：2018-07-26

申请号：US15935301

申请日：2018-03-26

Applicant: GOOGLE LLC

Inventor： Debargha Mukherjee ,  Jingning Han

IPC: H04N19/176

CPC classification number: H04N19/176 ,  H04N19/00 ,  H04N19/119 ,  H04N19/122 ,  H04N19/147 ,  H04N19/63

Abstract: Coding efficiency may be improved by subdividing a block into smaller sub-blocks for prediction. A first rate distortion value of a block optionally partitioned into smaller prediction sub-blocks of a first size is calculated using respective inter prediction modes and transforms of the first size. The residuals are used to encode the block using a transform of a second size smaller than the first size, generating a second rate distortion value. The values are compared to determine whether coding efficiency gains may result from inter predicting the smaller, second size sub-blocks. If so, the block is encoded by generating prediction residuals for the second size sub-blocks, and neighboring sub-blocks are grouped, where possible, based on common motion information. Each resulting composite residual block is transformed by a transform of the same size to generate another rate distortion value. The encoded block with the lowest rate distortion value is used.