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公开(公告)号:US20220417509A1
公开(公告)日:2022-12-29
申请号:US17901715
申请日:2022-09-01
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.
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公开(公告)号:US11336913B2
公开(公告)日:2022-05-17
申请号:US16799423
申请日:2020-02-24
Applicant: Apple Inc.
Inventor: Krishnakanth Rapaka , Alexandros Tourapis , David W. Singer
IPC: H04N19/503 , H04N19/86 , 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.
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公开(公告)号:US20210243451A1
公开(公告)日:2021-08-05
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 , H04N19/176 , H04N19/182
Abstract: Techniques are disclosed for 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.
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公开(公告)号:US12108036B2
公开(公告)日:2024-10-01
申请号:US17901715
申请日:2022-09-01
Applicant: Apple Inc.
Inventor: Alexandros Tourapis , Krishnakanth Rapaka , Dominik Mehlem
IPC: H04N19/117 , H04N19/126 , H04N19/13 , H04N19/182 , H04N19/82
CPC classification number: H04N19/117 , H04N19/126 , H04N19/182 , H04N19/13 , H04N19/82
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.
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公开(公告)号:US11962786B2
公开(公告)日:2024-04-16
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
CPC classification number: 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.
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公开(公告)号:US11936867B2
公开(公告)日:2024-03-19
申请号:US17234596
申请日:2021-04-19
Applicant: Apple Inc.
Inventor: Krishnakanth Rapaka , Jaehong Chon , Alexandros Tourapis , David W. Singer
IPC: H04N19/124 , H04N19/172 , H04N19/186 , H04N19/82
CPC classification number: H04N19/124 , H04N19/172 , H04N19/186 , H04N19/82
Abstract: Improved video coding and decoding techniques are described, including techniques to derive quantization step sizes adaptively with quantization step size table templates. Quantization techniques described provide finer-grained control over quantization with a more flexible quantization step size especially at higher degrees of quantization. This may result in improved overall compression quality. Other coding parameters, such as in-loop filtering parameters, may be derived based on the more flexible quantization parameters.
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公开(公告)号:US11863738B2
公开(公告)日:2024-01-02
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
CPC classification number: 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.
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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.
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公开(公告)号:US11196988B2
公开(公告)日:2021-12-07
申请号:US16669385
申请日:2019-10-30
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.
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公开(公告)号:US20210243455A1
公开(公告)日:2021-08-05
申请号:US17167413
申请日:2021-02-04
Applicant: Apple Inc.
Inventor: Krishnakanth Rapaka , Alexandros Tourapis , David William Singer
IPC: H04N19/176 , H04N19/119 , H04N19/50 , H04N19/159 , H04N19/136 , H04N19/103 , H04N19/124
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.
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