公开(公告)号：US20220360814A1

公开(公告)日：2022-11-10

申请号：US17736881

申请日：2022-05-04

Applicant: Apple Inc.

Inventor： Yeqing Wu ,  Alexandros Tourapis ,  Yunfei Zheng ,  Hsi-Jung Wu ,  Jun Xin ,  Albert E. Keinath ,  Mei Guo ,  Alican Nalci

IPC: H04N19/52 ,  H04N19/176 ,  H04N19/105 ,  H04N19/159 ,  H04N19/124

Abstract: An encoder or decoder can perform enhanced motion vector prediction by receiving an input block of data for encoding or decoding and accessing stored motion information for at least one other block of data. Based on the stored motion information, the encoder or decoder can generate a list of one or more motion vector predictor candidates for the input block in accordance with an adaptive list construction order. The encoder or decoder can predict a motion vector for the input block based on at least one of the one or more motion vector predictor candidates.

公开(公告)号：US11388419B2

公开(公告)日：2022-07-12

申请号：US16834693

申请日：2020-03-30

Applicant: Apple Inc.

Inventor： Mei Guo ,  Jun Xin ,  Hsi-Jung Wu ,  Alexandros Tourapis ,  Krishnakanth Rapaka

IPC: H04N19/159 ,  H04N19/182 ,  H04N19/176

Abstract: Improved video coding techniques include deriving prediction pixel blocks for use in intra-coding video and combined inter- and intra-coding video. In a first aspect, the techniques may include deriving value(s) for pixel location(s) of the prediction pixel block by, when a prediction direction vector assigned to the prediction vector points to quadrants I or III of a Cartesian plane, deriving the pixel location's value from pixel values in two regions of previously-decoded pixel data intercepted by extending the prediction direction vector in two opposite directions through the pixel location. When the prediction direction vector points toward quadrants II of the Cartesian plane, deriving the pixel location's value from pixel values in one region intercepted by the prediction direction vector through the pixel location, and from a second region intercepted by a vector that is orthogonal to the prediction direction vector.

公开(公告)号：US10757428B2

公开(公告)日：2020-08-25

申请号：US16156193

申请日：2018-10-10

Applicant: Apple Inc.

Inventor： Mei Guo ,  Jun Xin ,  Jun Xu ,  Yeping Su ,  Chris Chung ,  Xiaosong Zhou ,  Hsi-Jung Wu

IPC: H04N19/33 ,  H04N19/186 ,  H04N19/51 ,  H04N19/136 ,  H04N19/12

Abstract: Systems and methods are disclosed for reshaping HDR video content to improve compression efficiency while using standard encoding/decoding techniques. Input HDR video frames, e.g., represented in an IPT color space, may be reshaped before the encoding/decoding process and the corresponding reconstructed HDR video frames may then be reverse reshaped. The disclosed reshaping methods may be combinations of scene-based or segment-based methods.

公开(公告)号：US20190132594A1

公开(公告)日：2019-05-02

申请号：US15796313

申请日：2017-10-27

Applicant: Apple Inc.

Inventor： Chris Y. Chung ,  Mei Guo ,  Hsi-Jung Wu ,  Jingteng Xue ,  Jun Xin

IPC: H04N19/147 ,  H04N19/105 ,  H04N19/176 ,  H04N19/117 ,  H04N19/196 ,  H04N19/82

CPC classification number: H04N19/147 ,  H04N19/103 ,  H04N19/105 ,  H04N19/117 ,  H04N19/154 ,  H04N19/176 ,  H04N19/196 ,  H04N19/82

Abstract: Techniques are disclosed for coding pixel blocks of an input frame in which coding costs of a plurality of candidate coding modes are estimated, in which estimates of distortion include an estimate of noise of each respective candidate coding mode. Thus, evaluation of each coding mode may involve searching for a prediction reference for a pixel block according to the mode, and estimating coding cost of the respective candidate coding mode based at least in part on an estimate of noise associated with the respective coding mode. A coding mode for the input pixel block may be selected based on a comparison of the coding costs of the candidate coding modes, and the input pixel block may be coded according to the selected coding mode. By estimating noise associated with the candidate coding modes and, in particular, employing techniques to maintain consistent levels of noise across different frames of a coded video sequence, it is expected that perceived quality of coding will be improved.

公开(公告)号：US20180352264A1

公开(公告)日：2018-12-06

申请号：US15612806

申请日：2017-06-02

Applicant: Apple Inc.

Inventor： Mei Guo ,  Feng Yi ,  Jun Xin ,  Chris Y. Chung ,  Yeping Su ,  Xiaosong Zhou ,  Jun Xu ,  Hsi-Jung Wu ,  Jingteng Xue

IPC: H04N19/86 ,  H04N19/117

CPC classification number: H04N19/86 ,  H04N19/117 ,  H04N19/159

Abstract: Methods of in-loop deblocking filter for high dynamic range (HDR) video compression are disclosed. HDR processing and standard dynamic range (SDR) processing adopt different electro-optical transfer function (EOTF) to convert digital code words to linear luminance. For compressing HDR video, EOTF is proposed to be involved in the selection of two deblocking parameters, β and tC, which control the strength of deblocking filter. In local activity checking for filter decisions, the calculated local signal characteristics and the thresholds are adjusted according to EOTF. After deblocking filter, the clipping range is modified based on EOTF. The chroma deblocking filter is also extended to inter-inter block boundary.

公开(公告)号：US20180352259A1

公开(公告)日：2018-12-06

申请号：US15613081

申请日：2017-06-02

Applicant: Apple Inc.

Inventor： Mei Guo ,  Jun Xin ,  Yeping Su ,  Chris Chung ,  Dazhong Zhang ,  Xiaosong Zhou ,  Hsi-Jung Wu

IPC: H04N19/61 ,  H04N19/52 ,  H04N19/122 ,  H04N19/18 ,  H04N19/82 ,  H04N19/182 ,  H04N19/124 ,  H04N19/91

Abstract: Techniques are disclosed for coding high dynamic range (HDR) data. According to such techniques, HDR data may be converted to a domain of uniform luminance data. The uniform domain data may be coded by motion compensated predictive coding. The HDR data also may be coded by motion compensated predictive coding, using a coding parameter that is derived from a counterpart coding parameter of the coding of the uniform domain data. In another technique, HDR data may be coded using coding parameters that are derived from HDR domain processing but distortion measurements may be performed in a uniform domain.