公开(公告)号：US20200120345A1

公开(公告)日：2020-04-16

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

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：US20240040124A1

公开(公告)日：2024-02-01

申请号：US18358094

申请日：2023-07-25

Applicant: Apple Inc.

Inventor： Alican NALCI ,  Yunfei ZHENG ,  Hilmi Enes EGILMEZ ,  Yeqing WU ,  Yixin DU ,  Alexandros TOURAPIS ,  Jun XIN ,  Hsi-Jung WU ,  Arash VOSOUGHI ,  Dzung T. HOANG

IPC: H04N19/13 ,  H04N19/70 ,  H04N19/61 ,  H04N19/176

CPC classification number: H04N19/13 ,  H04N19/70 ,  H04N19/61 ,  H04N19/176

Abstract: A flexible coefficient coding (FCC) approach is presented. In the first aspect, spatial sub-regions are defined over a transform unit (TU) or a prediction unit (PU). These sub-regions organize the coefficient samples residing inside a TU or a PU into variable coefficient groups (VCGs). Each VCG corresponds to a sub-region inside a larger TU or PU. The shape of VCGs or the boundaries between different VCGs may be irregular, determined based on the relative distance of coefficient samples with respect to each other. Alternatively, the VCG regions may be defined according to scan ordering within a TU. Each VCG can encode a 1) different number of symbols for a given syntax element, or a 2) different number of syntax elements within the same TU or PU. Whether to code more symbols or more syntax elements may depend on the type of arithmetic coding engine used in a particular coding specification. For multi-symbol arithmetic coding (MS-AC), a VCG may encode a different number of symbols for a syntax element. For example, to encode absolute coefficient values inside a TU after performing a transform such as the discrete cosine transform (DCT), a VCG region may be defined around lower-frequency transform coefficients and for that VCG M-symbols can be encoded the absolute coefficient values. Another VCG region can be defined around the higher-frequency transform coefficients to encode K-symbols, where K may be different than M. For binary arithmetic coders (BACs), FCC allows for coding a variable number of syntax elements in different VCGs. In this case, one VCG in a TU may code M-syntax elements associated with signaling the absolute coefficient value, where each one of the M-syntax elements may have 2-symbols. Probability models and context derivation rules may be tailored for each VCG in a given TU or PU. Since each VCG may code a different number of symbols or syntax elements in different spatial locations of a TU or PU, different context models may be used for each VCG to provide better granularity for entropy modeling for arithmetic coding. Furthermore, different VCGs may also use different entropy coders including combinations of arithmetic coding, Golomb-Rice coding, Huffman coding.

公开(公告)号：US20240040120A1

公开(公告)日：2024-02-01

申请号：US18358111

申请日：2023-07-25

Applicant: Apple Inc.

Inventor： Hilmi Enes EGILMEZ ,  Yunfei ZHENG ,  Alican NALCI ,  Yeqing WU ,  Yixin DU ,  Guoxin JIN ,  Alexandros TOURAPIS ,  Jun XIN ,  Hsi-Jung WU

IPC: H04N19/122 ,  H04N19/61 ,  H04N19/176 ,  H04N19/70 ,  H04N19/159 ,  H04N19/136 ,  H04N19/18 ,  H04N19/186

CPC classification number: H04N19/122 ,  H04N19/61 ,  H04N19/176 ,  H04N19/70 ,  H04N19/159 ,  H04N19/136 ,  H04N19/18 ,  H04N19/186

Abstract: Video coders and decoders perform transform coding and decoding on blocks of video content according to an adaptively selected transform type. The transform types are organized into a hierarchy of transform sets where each transform set includes a respective number of transforms and each higher-level transform set includes the transforms of each lower-level transform set within the hierarchy. The video coders and video decoders may exchange signaling that establishes a transform set context from which a transform set that was selected for coding given block(s) may be identified. The video coders and video decoders may exchange signaling that establishes a transform decoding context from which a transform that was selected from the identified transform set to be used for decoding the transform unit. The block(s) may be coded and decoded by the selected transform.

公开(公告)号：US20230396819A1

公开(公告)日：2023-12-07

申请号：US18327364

申请日：2023-06-01

Applicant: APPLE INC.

Inventor： Ke ZHANG ,  Xiaoxia SUN ,  Shujie LIU ,  Xiaosong ZHOU ,  Jian LI ,  Xun SHI ,  Jiefu ZHAI ,  Albert E KEINATH ,  Hsi-Jung WU ,  Jingteng XUE ,  Xingyu ZHANG ,  Jun XIN

IPC: H04N21/2343 ,  H04N7/01 ,  G06V40/16 ,  G06V40/20 ,  G06V30/10 ,  H04N21/231

CPC classification number: H04N21/2343 ,  H04N7/0127 ,  H04N21/231 ,  G06V40/20 ,  G06V30/10 ,  G06V40/172

Abstract: A video delivery system generates and stores reduced bandwidth videos from source video. The system may include a track generator that executes functionality of application(s) to be used at sink devices, in which the track generator generates tracks from execution of the application(s) on source video and generates tracks having a reduced data size as compared to the source video. The track generator may execute a first instance of application functionality on the source video, which identifies region(s) of interest from the source video. The track generator further may downsample the source video according to downsampling parameters, and execute a second instance of application functionality on the downsampled video. The track generator may determine, from a comparison of outputs from the first and second instances of the application, whether the output from the second instance of application functionality is within an error tolerance of the output from the first instance of application functionality. If so, the track generator may generate a track from the downsampled video. In this manner, the system generates tracks that enable reliable application operation when processed by sink devices but also have reduced size as compared to source video.

公开(公告)号：US20210099507A1

公开(公告)日：2021-04-01

申请号：US16825381

申请日：2020-03-20

Applicant: Apple Inc.

Inventor： Fanyi DUANMU ,  Alexandros TOURAPIS ,  Jun XIN ,  Hsi-Jung WU ,  Xiaosong ZHOU

IPC: H04L29/06 ,  H04N13/344 ,  H04N13/161 ,  H04N13/194 ,  H04N13/111

Abstract: Techniques for multi-view video streaming are described in the present disclosure, wherein a viewport prediction may be employed at a client-end based on analysis of pre-fetched media item data and ancillary information. A streaming method may first prefetch a portion of content of a multi-view media item. The method may next identify a salient region from the prefetched content and may then download additional content of the media item that corresponds to the identified salient region.

公开(公告)号：US20210084332A1

公开(公告)日：2021-03-18

申请号：US16569725

申请日：2019-09-13

Applicant: Apple Inc.

Inventor： Fanyi DUANMU ,  Eduardo ASBUN ,  Xiaosong ZHOU ,  Jun XIN ,  Hsi-Jung WU ,  John SU ,  Samir GEHANI ,  Christopher FLICK ,  Shalini SAHOO

IPC: H04N19/597 ,  H04N19/176 ,  H04N19/187

Abstract: Techniques are disclosed for coding and delivering multi-view video in which the video is represented as a manifest file identifying a plurality of segments of the video available for download. The multi-view video may be partitioned spatially into a plurality of tiles that, in aggregate, encompass the entire spatial area of the video. The tiles are coded as segments contains coded video representing content contained within its respective tile. Tiles may be given different sizes based on saliency of the content within their respective regions. In this manner, tiles with high levels of interest may have relatively large spatial areas, which can lead to efficient coding in the presence of content motion.

公开(公告)号：US20210076054A1

公开(公告)日：2021-03-11

申请号：US16561478

申请日：2019-09-05

Applicant: Apple Inc.

Inventor： Mei GUO ,  Jun XIN ,  Yeping SU ,  Hsi-Jung WU ,  Alexandros TOURAPIS

IPC: H04N19/44 ,  H04N19/159 ,  H04N19/46 ,  H04N19/172 ,  H04N19/177

Abstract: Techniques for video exchange are disclosed in which a video source sends redundant copies of video coded at a given presentation time. A decoder may determine, from metadata stored with a first decoded frame, whether other decoded frames have been designated as correlated to the first decoded frame. If so, the decoder may fetch other decoding frames using time indicator values of other decoded frames in metadata stored with the first decoded frame. When other decoded frame(s) are found, the decoder may blend content of the first coded frame and the other decoded frame(s). The decoder may render the blended frame. When one such coded frame is an intra-coded frame, the proposed technique may alleviate beating artifacts by blending recovered data of the intra-coded frame with recovered data of another frame, which may be inter-coded.