公开(公告)号：US10277905B2

公开(公告)日：2019-04-30

申请号：US14853215

申请日：2015-09-14

Applicant: Google LLC

Inventor： Jingning Han ,  Yaowu Xu ,  Cheng Chen

IPC: H04N7/12 ,  H04N11/02 ,  H04B1/66 ,  H04N19/159 ,  H04N19/176 ,  H04N19/61 ,  H04N19/89 ,  H04N19/625 ,  H04N19/91 ,  H04N19/593 ,  H04N19/124 ,  H04N19/147 ,  H04N19/60 ,  H04N19/112

Abstract: Blocks of a frame of a non-baseband video signal are encoded by selecting between a staircase- or sinusoidal-based transform. For each prediction mode, a prediction block for encoding a current block is generated, a residual block is generated, the residual block is transformed using a sinusoidal-based transform and using a staircase-based transform, and first and second rate-distortion value for encoding the residual block using the sinusoidal-based transform and staircase-based transform are respectively generated. One of the staircase-based transform or the sinusoidal-based transform for encoding the residual block is selected based on a lowest value of the first rate-distortion value and the second rate-distortion value among results for each prediction mode, and the current block is encoded using the selected one of the staircase-based transform or the sinusoidal-based transform. Improved appearance for blocks having sharp edges can be achieved and lossless encoding is possible using the staircase-based transform.

公开(公告)号：US20190052912A1

公开(公告)日：2019-02-14

申请号：US15844894

申请日：2017-12-18

Applicant: GOOGLE LLC

Inventor： Cheng Chen ,  Jingning Han ,  Yaowu Xu

IPC: H04N19/86 ,  H04N19/176 ,  H04N19/42 ,  H04N19/117 ,  H04N19/14 ,  H04N19/139

Abstract: Multiple directional filters are applied against lines of pixels associated with a video block to determine filtered noise values. Each directional filter uses a different direction for filtering lines of pixels. For example, for each pixel value of the video block along a line of pixels having a direction corresponding to a directional filter, a difference can be determined between the pixel value and a corresponding pixel value along the line of pixels and outside of the video block. A value for line of pixels is determined as the sum of the absolute values of each of the differences, and a filtered noise value is determined as the sum of the values for the lines of pixels. The directional filter used to determine a lowest one of the filtered noise values for the video block is then selected. The video block is filtered using the selected directional filter.

公开(公告)号：US20250150574A1

公开(公告)日：2025-05-08

申请号：US18836951

申请日：2022-03-07

Applicant: Google LLC

Inventor： Bohan Li ,  Yaowu Xu ,  Jingning Han

IPC: H04N19/105 ,  H04N19/137 ,  H04N19/172 ,  H04N19/176

Abstract: A motion vector for a current block of a current frame is decoded. The motion vector for the current block refers to a first reference block in a first reference frame. A first prediction block of two or more prediction blocks is identified in the first reference frame and using the first reference block. A first grid-aligned block is identified based on the first reference block. A second reference block is identified using a motion vector of the first grid-aligned block in a second reference frame. A second prediction block of the two or more prediction blocks is identified in the second reference frame and using the second reference block. The two or more prediction blocks are combined to obtain a prediction block for the current block.

公开(公告)号：US11876974B2

公开(公告)日：2024-01-16

申请号：US17738105

申请日：2022-05-06

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

CPC classification number: H04N19/139 ,  H04N19/105 ,  H04N19/172 ,  H04N19/537 ,  H04N19/573 ,  H04N19/577

Abstract: Motion prediction using optical flow is determined to be available for a current frame in response to determining that a reference frame buffer includes, with respect to the current frame, a forward reference frame and a backward reference frame. A flag indicating whether a current block is encoded using optical flow is decoded. Responsive to determining that the flag indicates that the current block is encoded using optical flow, a motion vector is decoded for the current block; a location of an optical flow reference block is identified within an optical flow reference frame based on the motion vector; subsequent to identifying the location of the optical flow reference block, the optical flow reference block is generated using the forward reference frame and the backward reference frame without generating the optical flow reference frame; and the current block is decoded based on the optical flow reference block.

公开(公告)号：USRE49615E1

公开(公告)日：2023-08-15

申请号：US17093417

申请日：2020-11-10

Applicant: Google LLC

Inventor： Yaowu Xu ,  Jingning Han

IPC: H04N19/44 ,  H04N19/523 ,  H04L65/70 ,  H04N19/463 ,  H04N19/117 ,  H04N19/176 ,  H04N19/52 ,  H04N19/82 ,  H04N19/159 ,  H04N19/513

CPC classification number: H04N19/44 ,  H04L65/70 ,  H04N19/117 ,  H04N19/159 ,  H04N19/176 ,  H04N19/463 ,  H04N19/513 ,  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：US20230156221A1

公开(公告)日：2023-05-18

申请号：US17527590

申请日：2021-11-16

Applicant: GOOGLE LLC

Inventor： Bohan Li ,  Ching-Han Chiang ,  Jingning Han ,  Yao Yao

IPC: H04N19/597 ,  H04N19/80 ,  H04N19/139 ,  H04N19/167 ,  H04N19/182 ,  H04N19/176 ,  H04N19/57 ,  H04N19/52 ,  H04N19/583

CPC classification number: H04N19/597 ,  H04N19/80 ,  H04N19/139 ,  H04N19/167 ,  H04N19/182 ,  H04N19/176 ,  H04N19/57 ,  H04N19/52 ,  H04N19/583

Abstract: Mapping-aware coding tools for 360 degree videos adapt conventional video coding tools for 360 degree video data using parameters related to a spherical projection of the 360 degree video data. The mapping-aware coding tools perform motion vector mapping techniques, adaptive motion search pattern techniques, adaptive interpolation filter selection techniques, and adaptive block partitioning techniques. Motion vector mapping includes calculating a motion vector for a pixel of a current block by mapping the location of the pixel within a two-dimensional plane (e.g., video frame) onto a sphere and mapping a predicted location of the pixel on the sphere determined based on rotation parameters back onto the plane. Adaptive motion searching, adaptive interpolation filter selection, and adaptive block partitioning operate according to density distortion based on locations along the sphere. These mapping-aware coding tools contemplate changes to video information by the mapping of 360 degree video data into a conventional video format.

公开(公告)号：US20220353534A1

公开(公告)日：2022-11-03

申请号：US17866612

申请日：2022-07-18

Applicant: Google LLC

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

IPC: H04N19/60 ,  G06N7/00 ,  G06N20/10 ,  H04N19/12 ,  H04N19/176 ,  H04N19/137 ,  H04N19/463

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 a decoding operation, a probability model for decoding encoded bitstream video data associated with a transform kernel candidate for an encoded transform block is identified based on one or both of a first transform kernel candidate selected for an above neighbor transform block of the encoded transform block or a second transform kernel candidate selected for a left neighbor transform block of the encoded transform block. The encoded bitstream video data associated with the transform kernel candidate is decoded using the probability model.

公开(公告)号：US11284107B2

公开(公告)日：2022-03-22

申请号：US15683684

申请日：2017-08-22

Applicant: GOOGLE LLC

Inventor： Yaowu Xu ,  Bohan Li ,  Jingning Han

IPC: H04N19/58 ,  H04N19/587 ,  H04N19/80 ,  H04N19/176 ,  H04N19/182 ,  H04N19/44 ,  H04N19/59 ,  H04N19/527 ,  H04N19/105 ,  H04N19/567 ,  H04N19/54 ,  H04N19/56 ,  H04N19/523 ,  H04N19/172

Abstract: An optical flow reference frame is generated that can be used for inter prediction of blocks of a current frame in a video sequence. A first (e.g., forward) reference frame and a second (e.g., backward reference frame) are used in an optical flow estimation that produces a respective motion field for pixels of the current frame. The motion fields are used to warp the reference frames to the current frame. The warped reference frames are blended to forms the optical flow reference frame.

公开(公告)号：US20210112270A1

公开(公告)日：2021-04-15

申请号：US17132065

申请日：2020-12-23

Applicant: GOOGLE LLC

Inventor： Jingning Han ,  James Bankoski ,  Yaowu Xu

IPC: H04N19/573 ,  H04N19/70 ,  H04N19/567 ,  H04N19/52

Abstract: Dynamic motion vector referencing is used to predict motion within video blocks. A motion trajectory is determined for a current frame including a video block to encode or decode based on a reference motion vector used for encoding or decoding one or more reference frames of the current frame. One or more temporal motion vector candidates are then determined for predicting motion within the video block based on the motion trajectory. A motion vector is selected from a motion vector candidate list including the one or more temporal motion vector candidates and used to generate a prediction block. The prediction block is then used to encode or decode the video block. The motion trajectory is based on an order of video frames indicated by frame offset values encoded to a bitstream. The motion vector candidate list may include one or more spatial motion vector candidates.

公开(公告)号：US20210084336A1

公开(公告)日：2021-03-18

申请号：US17106898

申请日：2020-11-30

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 processor is configured to maintain, for encoding current values related to the transform coefficients a first line buffer and a second line buffer. The current values are arranged along a current scan-order anti-diagonal line. The first line buffer includes first values of a first scan-order anti-diagonal line. The second line buffer includes second values of a second scan-order anti-diagonal line. The processor is further configured to interleave the first values and the second values in a destination buffer; select, using the destination buffer, a probability distribution for coding a current value of the current values; entropy encode, in a compressed bitstream, the current value using the probability distribution; and replace, for coding values of an immediately subsequent scan-order anti-diagonal line to the current scan-order anti-diagonal line, one of the second line buffer or the first line buffer with the current scan-order anti-diagonal line.