公开(公告)号：US11438584B2

公开(公告)日：2022-09-06

申请号：US16994506

申请日：2020-08-14

Applicant: Apple Inc.

Inventor： Alexandros Tourapis ,  Krishnakanth Rapaka ,  Dominik Mehlem

IPC: H04N19/117 ,  H04N19/82 ,  H04N19/124 ,  H04N19/159 ,  H04N19/105 ,  H04N19/126 ,  H04N19/182 ,  H04N19/13

Abstract: A system comprises an encoder configured to compress video data. The encoder includes an adaptive bilateral filter that uses look-up tables. The encoder may encode one or more adaptive adjustment factors to be used by a decoder to select or adjust look-up tables used to decode the compressed video data.

公开(公告)号：US20220279194A1

公开(公告)日：2022-09-01

申请号：US17671512

申请日：2022-02-14

Applicant: Apple Inc.

Inventor： Krishnakanth Rapaka ,  Alexandros Tourapis ,  David William Singer

IPC: H04N19/176 ,  H04N19/103 ,  H04N19/119 ,  H04N19/124 ,  H04N19/136 ,  H04N19/159 ,  H04N19/50

Abstract: A multi-stage coding method includes receiving an input block of data for encoding and one or more previously coded samples associated with the input block. The input block is segmented into at least a first sub-region and a second sub-region. A prediction for the first sub-region is generated based on the one or more previously coded samples. Residual data for the first sub-region is obtained using the prediction for the first sub-region. A reconstruction of the first sub-region is generated using the residual data for the first sub-region and the prediction for the first sub-region. A prediction for the second sub-region is generated using the reconstruction of the first sub-region. Residual data for the second sub-region is obtained using the prediction for the second sub-region. The input block is encoded based in part on the residual data for the first region and the residual data for the second region.

公开(公告)号：US11252418B2

公开(公告)日：2022-02-15

申请号：US17167413

申请日：2021-02-04

Applicant: Apple Inc.

Inventor： Krishnakanth Rapaka ,  Alexandros Tourapis ,  David William Singer

IPC: H04N19/176 ,  H04N19/103 ,  H04N19/119 ,  H04N19/124 ,  H04N19/136 ,  H04N19/159 ,  H04N19/50

Abstract: A multi-stage coding method includes receiving an input block of data for encoding and one or more previously coded samples associated with the input block. The input block is segmented into at least a first sub-region and a second sub-region. A prediction for the first sub-region is generated based on the one or more previously coded samples. Residual data for the first sub-region is obtained using the prediction for the first sub-region. A reconstruction of the first sub-region is generated using the residual data for the first sub-region and the prediction for the first sub-region. A prediction for the second sub-region is generated using the reconstruction of the first sub-region. Residual data for the second sub-region is obtained using the prediction for the second sub-region. The input block is encoded based in part on the residual data for the first region and the residual data for the second region.

公开(公告)号：US20210160523A1

公开(公告)日：2021-05-27

申请号：US16799423

申请日：2020-02-24

Applicant: Apple Inc.

Inventor： Krishnakanth Rapaka ,  Alexandros Tourapis ,  David W. Singer

IPC: H04N19/503 ,  H04N19/82 ,  H04N19/86

Abstract: Predictive coding techniques may include resampling of reference pictures, where various coding parameters are determined based on the resolution(s) or pixel format(s) of the prediction references. In a first aspect, lists of weights for use in weighted prediction are based on the resolution(s) of prediction references. In a second aspect, resampling filter parameters are selected based on the resolutions of prediction references. In a third aspect, deblocking filter parameters are based on the resolution(s) of prediction references.

公开(公告)号：US20210051320A1

公开(公告)日：2021-02-18

申请号：US16994506

申请日：2020-08-14

Applicant: Apple Inc.

Inventor： Alexandros Tourapis ,  Krishnakanth Rapaka ,  Dominik Mehlem

IPC: H04N19/117 ,  H04N19/126 ,  H04N19/182

Abstract: A system comprises an encoder configured to compress video data. The encoder includes an adaptive bilateral filter that uses look-up tables. The encoder may encode one or more adaptive adjustment factors to be used by a decoder to select or adjust look-up tables used to decode the compressed video data.

公开(公告)号：US20180352240A1

公开(公告)日：2018-12-06

申请号：US15613172

申请日：2017-06-03

Applicant: Apple Inc.

Inventor： Krishnakanth Rapaka ,  Mukta Gore ,  Sunder Venkateswaran ,  Xiaohua Yang ,  Xiang Fu ,  Francesco Iacopino ,  Linfeng Guo

IPC: H04N19/187 ,  H04N19/51 ,  H04N19/31 ,  H04N19/39

Abstract: Techniques for encoding video with temporal layering are described, comprising predicting a sequence of pictures with a motion prediction reference pattern having a number of virtual temporal layers, and encoding the sequence of pictures into an encoded bitstream with a temporal layering syntax, wherein a number of signaled temporal layers is less than the number of virtual temporal layers. The number of signaled temporal layers may be determined from a target highest frame rate, a target base layer frame rate, and the number of virtual temporal layers.

公开(公告)号：US11843776B2

公开(公告)日：2023-12-12

申请号：US17843160

申请日：2022-06-17

Applicant: Apple Inc.

Inventor： Krishnakanth Rapaka ,  Munehiro Nakazato ,  Jiandong Shen ,  Ganesh G. Yadav ,  Sorin Constantin Cismas ,  Jim C. Chou ,  Hao Pan

IPC: H04N19/124 ,  H04N19/60 ,  H04N19/126

CPC classification number: H04N19/124 ,  H04N19/126 ,  H04N19/60

Abstract: In one implementation, a method of encoding an image is performed at a device including one or more processors and non-transitory memory. The method includes determining a category of a spatial portion of an image based on a relation between a plurality of thresholds associated with a plurality of quantization scaling parameters and a bit rate of the spatial portion of the image at the plurality of quantization scaling parameters. The method includes quantizing the spatial portion of the image based on the categorization.

公开(公告)号：US20220248045A1

公开(公告)日：2022-08-04

申请号：US17723788

申请日：2022-04-19

Applicant: Apple Inc.

Inventor： Krishnakanth Rapaka ,  Alexandros Tourapis ,  David W. Singer

IPC: H04N19/503 ,  H04N19/86 ,  H04N19/82

Abstract: Predictive coding techniques may include resampling of reference pictures, where various coding parameters are determined based on the resolution(s) or pixel format(s) of the prediction references. In a first aspect, lists of weights for use in weighted prediction are based on the resolution(s) of prediction references. In a second aspect, resampling filter parameters are selected based on the resolutions of prediction references. In a third aspect, deblocking filter parameters are based on the resolution(s) of prediction references.

公开(公告)号：US20220166969A1

公开(公告)日：2022-05-26

申请号：US17540356

申请日：2021-12-02

Applicant: Apple Inc.

Inventor： Alexandros Tourapis ,  Jungsun Kim ,  Krishnakanth Rapaka ,  David W. Singer

IPC: H04N19/105 ,  H04N19/172 ,  H04N19/174 ,  H04N19/184 ,  H04N19/513 ,  H04N19/70

Abstract: Techniques for encoding video with motion compensation include a compressed bitstream syntax that includes a list of all motion prediction reference frames without distinguishing between short-term reference frame and long-term reference frames. The list of reference frames may be provided in a slice header and may apply to encoded data video data within the corresponding slice. The list may be prefaced with a single number indicating the total number of reference frames. In an aspect delta POC reference numbers may be encoded with a flag indicating the sign of the delta POC when the absolute value of the POC is not equal to zero. In another aspect, a flag may be encoded for every reference frame indicating if POC information should be used when scaling prediction references, and a weighting parameter may be included when POC information should be used.