公开(公告)号：US20220377376A1

公开(公告)日：2022-11-24

申请号：US17866707

申请日：2022-07-18

Applicant: GOOGLE LLC

Inventor： Jingning Han ,  James Zern ,  Linfeng Zhang ,  Ching-Han Chiang ,  Yaowu Xu

IPC: H04N19/60 ,  H04N19/129 ,  H04N19/88 ,  H04N19/184 ,  H04N19/13

Abstract: A transform type is obtained for decoding the transform block of transform coefficients. A template for entropy-decoding values related to the transform coefficients is selected based on the transform type. The template indicates, for a to-be-coded value, positions of already coded values. A context for selecting a probability distribution for entropy decoding a current value of the values is determined using the template. The current value is entropy decoded from a compressed bitstream using the probability distribution.

公开(公告)号：US11405645B2

公开(公告)日：2022-08-02

申请号：US15630071

申请日：2017-06-22

Applicant: GOOGLE LLC

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

IPC: H04N11/02 ,  H04N19/60 ,  G06N7/00 ,  G06N20/10 ,  H04N19/12 ,  H04N19/176 ,  H04N19/137 ,  H04N19/463 ,  H04N11/04 ,  H04N19/127 ,  H04N19/157

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：US10951885B2

公开(公告)日：2021-03-16

申请号：US16117563

申请日：2018-08-30

Applicant: GOOGLE LLC

Inventor： Jingning Han ,  Paul Wilkins ,  Yaowu Xu

IPC: H04N19/105 ,  H04N19/182 ,  H04N19/167 ,  H04N19/177 ,  H04N19/117 ,  H04N19/137

Abstract: A method for using an alternate frame reference (ARF) includes selecting an anchor frame and video frames, where the anchor frame includes an anchor block, and the anchor block includes an anchor pixel; identifying, for the anchor block of the anchor frame, respective reference blocks in the video frames; determining, for the anchor pixel and using an anchor patch, respective distances between the anchor pixel and respective co-located reference pixels of the respective reference blocks, where the anchor patch includes anchor patch pixels, and a respective distance, of the respective distances, between the anchor pixel and a respective co-located reference pixel is determined using the anchor patch pixels and co-located reference pixels; determining, using the respective distances, respective weights; determining, using the respective weights, an ARF pixel that is co-located with the anchor pixel; and encoding, in a compressed bitstream, the ARF.

公开(公告)号：US20200275098A1

公开(公告)日：2020-08-27

申请号：US16858805

申请日：2020-04-27

Applicant: GOOGLE LLC

Inventor： Cheng Chen ,  Jingning Han

IPC: H04N19/117 ,  H04N19/426 ,  H04N19/172

Abstract: A memory-efficient filtering approach is used to code images and video. A buffer having a fixed size based on a size of processing units to use for filtering a video frame is allocated. For each of the processing units, pre-filtered pixel values are copied from a respective region of the video frame to the buffer based on a writing point for the video frame and an offset applied to the writing point, filtering is performed against the pre-filtered pixel values from the buffer to produce filtered pixel values, and the filtered pixel values are written to the video frame based on the writing point and the offset. The filtering may be performed using a loop restoration tool, such as where the pre-filtered pixel values are output from a constrained directional enhancement filter (CDEF) tool. Alternatively, the filtering may be performed using the CDEF tool or another coding tool.

公开(公告)号：US10694180B2

公开(公告)日：2020-06-23

申请号：US15939691

申请日：2018-03-29

Applicant: GOOGLE LLC

Inventor： Jingning Han ,  Yaowu Xu

IPC: H04N19/176 ,  H04N19/115 ,  H04N19/60 ,  H04N19/91 ,  H04N19/157 ,  H04N19/13

Abstract: Entropy coding of transform partitioning information may include decoding a current block by determining a probability for entropy decoding a transform partitioning flag based on a transform block size of an adjacent block that is available for decoding, entropy decoding the transform partitioning flag for the current block using the probability, generating a reconstructed block based on the current block by, on a condition that the transform partitioning flag indicates that transform partitioning is omitted for the current block, inverse transforming the current block using a current block size inverse transform, and, on a condition that the transform partitioning flag indicates transform partitioning for the current block, identifying sub-blocks from the current block, wherein each sub-block from the sub-blocks has a sub-block size smaller than the current block size, inverse transforming the sub-blocks using sub-block size inverse transforms, and generating the reconstructed block based on the residual block.

公开(公告)号：US10659788B2

公开(公告)日：2020-05-19

申请号：US15817369

申请日：2017-11-20

Applicant: GOOGLE LLC

Inventor： Yaowu Xu ,  Bohan Li ,  Jingning Han

IPC: H04N19/00 ,  H04N19/139 ,  H04N19/105 ,  H04N19/577 ,  H04N19/573 ,  H04N19/172 ,  H04N19/537

Abstract: An optical flow reference frame portion (e.g., a block or an entire frame) is generated that can be used for inter prediction of blocks of a current frame in a video sequence. A forward reference frame and a backward reference frame are used in an optical flow estimation that produces a respective motion field for pixels of a current frame. The motion fields are used to warp some or all pixels of the reference frames to the pixels of the current frame. The warped reference frame pixels are blended to form the optical flow reference frame portion. The inter prediction may be performed as part of encoding or decoding portions of the current frame.

公开(公告)号：US20200077083A1

公开(公告)日：2020-03-05

申请号：US16117563

申请日：2018-08-30

Applicant: GOOGLE LLC

Inventor： Jingning Han ,  Paul Wilkins ,  Yaowu Xu

IPC: H04N19/105 ,  H04N19/182 ,  H04N19/167 ,  H04N19/177 ,  H04N19/117 ,  H04N19/137

Abstract: A method for using an alternate frame reference (ARF) includes selecting an anchor frame and video frames, where the anchor frame includes an anchor block, and the anchor block includes an anchor pixel; identifying, for the anchor block of the anchor frame, respective reference blocks in the video frames; determining, for the anchor pixel and using an anchor patch, respective distances between the anchor pixel and respective co-located reference pixels of the respective reference blocks, where the anchor patch includes anchor patch pixels, and a respective distance, of the respective distances, between the anchor pixel and a respective co-located reference pixel is determined using the anchor patch pixels and co-located reference pixels; determining, using the respective distances, respective weights; determining, using the respective weights, an ARF pixel that is co-located with the anchor pixel; and encoding, in a compressed bitstream, the ARF.

公开(公告)号：US20200007890A1

公开(公告)日：2020-01-02

申请号：US16561165

申请日：2019-09-05

Applicant: GOOGLE LLC

Inventor： Jingning Han ,  Yaowu Xu

IPC: H04N19/573 ,  H04N19/52 ,  H04N19/107 ,  H04N19/172 ,  H04N19/176 ,  H04N19/91 ,  H04N19/82 ,  H04N19/86 ,  H04N19/61 ,  H04N19/70 ,  H04N19/126 ,  H04N5/225 ,  H04N19/567 ,  H04N19/577

Abstract: A prediction scheme is selected for encoding or decoding a video block. A first compound motion block can be determined by weighting distances from a first reference frame to the video frame and from a second reference frame to the video frame using one or more quantized weighting coefficients. A second compound motion block can be determined based on an average of pixel values a video block of the first reference frame and pixel values from a video block of the second reference frame. One of the first compound motion block or the second compound motion block is selected and used to generate a prediction block. Alternatively, data encoded to a bitstream including the video frame can be used to determine which compound motion block to use to generate the prediction block. The current block of the video frame is then encoded or decoded using the prediction block.

公开(公告)号：US10523944B2

公开(公告)日：2019-12-31

申请号：US16402411

申请日：2019-05-03

Applicant: GOOGLE LLC

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

IPC: H04N19/00 ,  H04N19/129 ,  H04N19/159 ,  H04N19/61 ,  H04N19/86 ,  H04N19/13 ,  H04N19/82 ,  H04N19/124 ,  H04N19/156 ,  H04N19/18 ,  H04N19/423 ,  H04N19/91 ,  H04N7/18 ,  H04N11/00

Abstract: Generating a new scan order includes incrementing a next index value after assigning the next index value to a coefficient in the new scan order; assigning, to a first coefficient at a first scan index m in the original scan order, a first scan index in the new scan order, the first coefficient is a context coefficient for entropy coding a parent coefficient that is at a parent scan index n in the original scan order; adding, to a list, a first item indicative of the parent coefficient and parent scan index n; before assigning a second scan index to a second coefficient that is at a second index m+j in the original scan order, wherein j>1, assigning the next index value to the parent coefficient, and removing the first item from the list; and assigning the next index value to the second coefficient in the new scan order.

公开(公告)号：US20190394463A1

公开(公告)日：2019-12-26

申请号：US16016768

申请日：2018-06-25

Applicant: GOOGLE LLC

Inventor： Cheng Chen ,  Jingning Han ,  Yaowu Xu

IPC: H04N19/117 ,  H04N19/176 ,  H04N19/46 ,  H04N19/186

Abstract: Systems and methods are disclosed for encoding and decoding video. For example, methods may include: accessing an encoded bitstream; reconstructing an image including multiple color planes based on data from the encoded bitstream; decoding a first filter level from the encoded bitstream, wherein the first filter level specifies one or more thresholds that are used to select a length for a deblocking filter; decoding a second filter level from the encoded bitstream, wherein the second filter level specifies one or more thresholds that are used to select a length for a deblocking filter; after reconstruction of the image, applying a deblocking filter to a first color plane of the image using the first filter level; and, after reconstruction of the image, applying a deblocking filter to a second color plane of the image using the second filter level.