公开(公告)号：US20190020900A1

公开(公告)日：2019-01-17

申请号：US15648500

申请日：2017-07-13

Applicant: GOOGLE LLC

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

IPC: H04N19/70 ,  H04N19/176 ,  H04N19/50 ,  H04N19/44 ,  H04N19/13

Abstract: Video syntax elements are coded using a context tree. Context information used for coding previously-coded syntax elements is identified. A context tree is produced by separating the previously-coded syntax elements into data groups based on the context information. The context tree includes nodes representing the data groups. Separating the previously-coded syntax elements can include applying separation criteria against values of the context information to produce at least some of the nodes. Context information is then identified for another set of syntax elements to be coded. One of the nodes of the context tree is identified based on values of the context information associated with one of the other set of syntax elements. That syntax element is then coded according to a probability model associated with the identified node. The context tree can be used to encode or decode syntax elements.

公开(公告)号：US20250150641A1

公开(公告)日：2025-05-08

申请号：US18836986

申请日：2022-12-29

Applicant: GOOGLE LLC

Inventor： Jingning Han ,  Yaowu Xu ,  Joseph Young ,  In Suk Chong ,  Debargha Mukherjee

IPC: H04N19/91 ,  H04N19/18 ,  H04N19/70

Abstract: Entropy coding a sequence of syntax elements is described where an observation for a syntax element of the sequence is determined, and the observation is arithmetic coded using the probability model. Thereafter, the probability model is updated using a time-variant update rate to produce an updated probability model. Updating the probability model includes regularizing one or more probability values of the probability model so no probability of the updated probability model is below a defined minimum resolution. As a result, the use of a minimum probability value during the arithmetic coding, which can distort probability model, may be omitted.

公开(公告)号：US20250119577A1

公开(公告)日：2025-04-10

申请号：US18901214

申请日：2024-09-30

Applicant: GOOGLE LLC

Inventor： Xiang Li ,  Debargha Mukherjee ,  Yaowu Xu ,  Jingning Han

IPC: H04N19/593 ,  H04N19/11 ,  H04N19/117 ,  H04N19/119 ,  H04N19/136 ,  H04N19/176 ,  H04N19/184 ,  H04N19/186

Abstract: Encoding using chroma intra prediction with filtering includes encoding a current block from a current frame, which includes obtaining a first chroma prediction value for a current chroma pixel using a current spatial intra prediction mode, obtaining a current luma prediction value for a current luma pixel collocated with the current chroma pixel, obtaining a second chroma prediction value for the current chroma pixel for the current chroma component by applying derived filter coefficients to the current luma prediction value, obtaining, as a third chroma prediction value for the current chroma pixel for the current chroma component, a weighted average of the first chroma prediction value and the second chroma prediction value, obtaining encoded chroma pixel data for the current chroma pixel by encoding the current chroma pixel using the third chroma prediction value, and including the encoded chroma pixel data in the encoded block data.

公开(公告)号：US20250071319A1

公开(公告)日：2025-02-27

申请号：US18811455

申请日：2024-08-21

Applicant: Google LLC

Inventor： Yunqing Wang ,  Jingning Han ,  Bohan Li ,  Yaowu Xu

IPC: H04N19/52 ,  H04N19/105 ,  H04N19/139 ,  H04N19/176 ,  H04N19/182 ,  H04N19/46

Abstract: Techniques are described for motion vector resolution based motion vector prediction for video coding. A motion vector precision level for coding a current block is determined, a motion vector reference list is generated using the motion vector precision level, an index into the motion vector reference list is determined, where the index identifies a motion vector candidate from the motion vector reference list, and a motion vector for inter prediction of the current block is coded using the motion vector candidate. The motion vector precision level can indicate a single resolution for generating the motion vector reference list or a first resolution for generating the motion vector reference list and a second resolution for coding motion vector residuals of the motion vector.

公开(公告)号：US12219143B2

公开(公告)日：2025-02-04

申请号：US17775565

申请日：2020-11-09

Applicant: Google LLC

Inventor： Jingning Han ,  Yue Sun ,  Yaowu Xu

IPC: H04N19/13 ,  H04N19/126 ,  H04N19/91

Abstract: Entropy coding a sequence of symbols is described. A first probability model for entropy coding is selected. At least one symbol of the sequence is coded using a probability determined using the first probability model. The probability according to the first probability model is updated with an estimation of a second probability model to entropy code a subsequent symbol. The combination may be a fixed or adaptive combination.

公开(公告)号：US20240422309A1

公开(公告)日：2024-12-19

申请号：US18820598

申请日：2024-08-30

Applicant: GOOGLE LLC

Inventor： Lin Zheng ,  Yaowu Xu ,  Lester Lu ,  Jingning Han ,  Bohan Li

IPC: H04N19/105 ,  H04N19/139 ,  H04N19/172 ,  H04N19/573

Abstract: Methods, systems and apparatuses are disclosed including computer readable medium storing instructions used to encode or decode a video or a bitstream encodable or decodable using disclosed steps. The steps include reconstructing a first reference frame and a second reference frame for a current frame to be encoded or decoded, projecting motion vectors of the first reference frame and the second reference frame onto pixels of a current reference frame resulting in a first pixel in the current reference frame being associated with a plurality of projected motion vectors, and selecting a first projected motion vector from the plurality of projected motion vectors as a selected motion vector associated with the first pixel to be used for determining a pixel value of the first pixel, the selection based on magnitudes of the respective ones of the plurality of projected motion vectors.

公开(公告)号：US20240380924A1

公开(公告)日：2024-11-14

申请号：US18635323

申请日：2024-04-15

Applicant: GOOGLE LLC

Inventor： Bohan Li ,  Debargha Mukherjee ,  Yaowu Xu ,  Jingning Han

IPC: H04N19/60 ,  H04N19/159 ,  H04N19/176 ,  H04N19/70

Abstract: Decoding a current block of a current frame includes decoding, from a compressed bitstream, one or more syntax elements indicating that a geometric transformation is to be applied; applying the geometric transformation to at least a portion of the current frame to obtain a transformed portion; and obtaining a prediction of the current block based on the transformed portion and an intra-prediction mode.

公开(公告)号：US20240305802A1

公开(公告)日：2024-09-12

申请号：US18276407

申请日：2021-02-09

Applicant: Google LLC

Inventor： Cheng Chen ,  Jingning Han ,  Hui Su ,  Yaowu Xu

IPC: H04N19/44 ,  H04N19/14 ,  H04N19/176 ,  H04N19/186

CPC classification number: H04N19/44 ,  H04N19/14 ,  H04N19/176 ,  H04N19/186

Abstract: Syntax elements are written to a bitstream to designate bit depth precision for palette mode coding of video blocks. During encoding, a bit depth to use for palette mode coding a current block may be based on an input video signal including the current block or based on some change in bit depth precision. A prediction residual for the current block is encoded to a bitstream along with syntax elements indicative of the bit depth used for the palette mode coding of the current block. In particular, the syntax elements include a first element indicating the palette mode coding bit depth used and a second element indicating whether to apply a bit offset to the palette mode coding bit depth. During decoding, values of the syntax elements are read from the bitstream and used to determine a bit depth for palette mode coding the encoded block.

公开(公告)号：US11991392B2

公开(公告)日：2024-05-21

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

CPC classification number: H04N19/60 ,  H04N19/129 ,  H04N19/13 ,  H04N19/184 ,  H04N19/88

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：US11665365B2

公开(公告)日：2023-05-30

申请号：US16131133

申请日：2018-09-14

Applicant: GOOGLE LLC

Inventor： Bohan Li ,  Yaowu Xu ,  Jingning Han

IPC: H04N19/52 ,  H04N19/176 ,  H04N19/577

CPC classification number: H04N19/52 ,  H04N19/176 ,  H04N19/577

Abstract: Video coding may include generating, by a processor executing instructions stored on a non-transitory computer-readable medium, an encoded frame by encoding a current frame from an input bitstream, by generating a reference coframe spatiotemporally corresponding to the current frame, wherein the current frame is a frame from a sequence of input frames, wherein each frame from the sequence of input frames has a respective sequential location in the sequence of input frames, and wherein the current frame has a current sequential location in the sequence of input frames, and encoding the current frame using the reference coframe. Video coding may include including the encoded frame in an output bitstream and outputting the output bitstream.