-
公开(公告)号:US12206842B2
公开(公告)日:2025-01-21
申请号:US18424445
申请日:2024-01-26
Applicant: GOOGLE LLC
Inventor: Yaowu Xu , Bohan Li , Jingning Han
IPC: H04N19/105 , H04N19/139 , H04N19/172 , H04N19/573
Abstract: A motion field estimate determined using motion vector information of two or more reference frames of a current/encoded frame is used to derive a motion vector for inter-prediction of the current/encoded frame. Motion trajectory information, including concatenated motion vectors and locations of the current/encoded frame at which those concatenated motion vectors point, is determined by concatenating motion vectors of the reference frames. A motion field estimate is determined using the motion trajectory information and, in some cases, by interpolating unavailable motion vectors using neighbors. The motion field estimate is used to determine a co-located reference frame for the current/encoded frame, and an inter-prediction process is performed for the current/encoded frame using a motion vector derived using the co-located reference frame. During decoding, the motion field estimate may be determined using motion vectors signaled within a bitstream and without additional side information, thereby improving prediction coding efficiency.
-
公开(公告)号:US12075048B2
公开(公告)日:2024-08-27
申请号:US18188364
申请日:2023-03-22
Applicant: GOOGLE LLC
Inventor: Yaowu Xu , Paul Gordon Wilkins , James Bankoski
Abstract: A system, apparatus, and method for encoding and decoding a video image having a plurality of frames is disclosed. Encoding and decoding the video image can include selecting, for a current block, a prediction mode from a plurality of prediction modes; identifying, for the current block, a quantization value; selecting, for the current block, a probability distribution from a plurality of probability distributions based on the identified quantization value using a processor; and entropy encoding the selected prediction mode using the selected probability distribution.
-
公开(公告)号:US20240195979A1
公开(公告)日:2024-06-13
申请号:US18542997
申请日:2023-12-18
Applicant: GOOGLE LLC
Inventor: Yaowu Xu , Bohan Li , Jingning Han
IPC: H04N19/139 , H04N19/105 , H04N19/172 , H04N19/537 , H04N19/573 , H04N19/577
CPC classification number: H04N19/139 , H04N19/105 , H04N19/172 , H04N19/537 , H04N19/573 , H04N19/577
Abstract: A motion vector for a current block of a current frame is decoded from a compressed bitstream. A location of a reference block within an un-generated reference frame is identified. The reference block is generated using a forward reference frame and a backward reference frame without generating the un-generated reference frame. The reference block is generated by identifying an extended reference block by extending the reference block at each boundary of the reference block by a number of pixels related to a filter length of a filter used in sub-pixel interpolation; and generating pixel values of only the extended reference block by performing a projection using the forward reference frame and the backward reference frame without generating the whole of the un-generated reference frame. The current block is then decoded based on the reference block and the motion vector.
-
公开(公告)号:US11917128B2
公开(公告)日:2024-02-27
申请号:US17090094
申请日:2020-11-05
Applicant: GOOGLE LLC
Inventor: Bohan Li , Yaowu Xu , Jingning Han
IPC: H04N19/105 , H04N19/172 , H04N19/573 , H04N19/139
CPC classification number: H04N19/105 , H04N19/139 , H04N19/172 , H04N19/573
Abstract: A motion field estimate determined using motion vector information of two or more reference frames of a current/encoded frame is used to derive a motion vector for inter-prediction of the current/encoded frame. Motion trajectory information, including concatenated motion vectors and locations of the current/encoded frame at which those concatenated motion vectors point, is determined by concatenating motion vectors of the reference frames. A motion field estimate is determined using the motion trajectory information and, in some cases, by interpolating unavailable motion vectors using neighbors. The motion field estimate is used to determine a co-located reference frame for the current/encoded frame, and an inter-prediction process is performed for the current/encoded frame using a motion vector derived using the co-located reference frame. During decoding, the motion field estimate may be determined using motion vectors signaled within a bitstream and without additional side information, thereby improving prediction coding efficiency.
-
公开(公告)号:US11870983B2
公开(公告)日:2024-01-09
申请号:US16995078
申请日:2020-08-17
Applicant: Google LLC
Inventor: Yaowu Xu , Jingning Han , Cheng Chen
IPC: H04N19/186 , H04N19/117 , H04N19/46 , H04N19/176
CPC classification number: H04N19/117 , H04N19/176 , H04N19/186 , H04N19/46
Abstract: Techniques for encoding and decoding image data are described. An image is reconstructed and deblocked. A respective deblocking filter is identified for different color planes of the image. The deblocking filters may include those having different lengths for a luma plane as compared to one or more chroma planes of the image. One or more of the color planes, such as the luma plane, may have different filters for filtering reconstructed pixels vertically as compared to filtering the reconstructed pixels horizontally.
-
公开(公告)号:USRE49727E1
公开(公告)日:2023-11-14
申请号:US17200761
申请日:2021-03-12
Applicant: GOOGLE LLC
Inventor: Yaowu Xu , Paul Wilkins , James Bankoski
IPC: H04N19/61 , H04N19/91 , H04N19/82 , H04N19/17 , H04N19/593 , H04N19/44 , H04N19/174 , H04N19/176 , H04N19/436 , H04N19/51
CPC classification number: H04N19/61 , H04N19/174 , H04N19/176 , H04N19/436 , H04N19/44 , H04N19/51 , H04N19/593 , H04N19/82 , H04N19/91
Abstract: An apparatus for decoding frames of a compressed video data stream having at least one frame divided into partitions, includes a memory and a processor configured to execute instructions stored in the memory to read partition data information indicative of a partition location for at least one of the partitions, decode a first partition of the partitions that includes a first sequence of blocks, decode a second partition of the partitions that includes a second sequence of blocks identified from the partition data information using decoded information of the first partition.
-
公开(公告)号:US11800136B2
公开(公告)日:2023-10-24
申请号:US17868011
申请日:2022-07-19
Applicant: GOOGLE LLC
Inventor: Jingning Han , Yaowu Xu , James Bankoski , Jia Feng
IPC: H04N19/00 , H04N19/51 , H04N19/196 , H04N19/182 , H04N19/176 , H04N19/513 , H04N19/433 , H04N19/55
CPC classification number: H04N19/51 , H04N19/176 , H04N19/182 , H04N19/196 , H04N19/433 , H04N19/513 , H04N19/55
Abstract: Decoding a current block of a current frame includes obtaining motion trajectories between the current frame and at least one previously coded frame by projecting motion vectors from the at least one previously coded frame onto the current frame. A motion field is obtained between the current frame and a reference frame used for coding the current frame. The motion field is obtained by extending the motion trajectories from the current frame towards the reference frame. A motion vector for the current block is identified based on the motion field. A prediction block is obtained for the current block using a reference block of the reference frame identified using the motion vector.
-
公开(公告)号:US20230308679A1
公开(公告)日:2023-09-28
申请号:US18323613
申请日:2023-05-25
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 using motion prediction coding with coframe motion vectors includes generating a reference coframe spatiotemporally concurrent with a current 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, generating an encoded frame by encoding the current frame using the reference coframe, including the encoded frame in an encoded bitstream, and outputting the encoded bitstream.
-
公开(公告)号:US20230007260A1
公开(公告)日:2023-01-05
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:US20220264109A1
公开(公告)日:2022-08-18
申请号:US17738105
申请日:2022-05-06
Applicant: GOOGLE LLC
Inventor: Yaowu Xu , Bohan Li , Jingning Han
IPC: H04N19/139 , H04N19/105 , H04N19/577 , H04N19/573 , H04N19/172 , H04N19/537
Abstract: Motion prediction using optical flow is determined to be available for a current frame in response to determining that a reference frame buffer includes, with respect to the current frame, a forward reference frame and a backward reference frame. A flag indicating whether a current block is encoded using optical flow is decoded. Responsive to determining that the flag indicates that the current block is encoded using optical flow, a motion vector is decoded for the current block; a location of an optical flow reference block is identified within an optical flow reference frame based on the motion vector; subsequent to identifying the location of the optical flow reference block, the optical flow reference block is generated using the forward reference frame and the backward reference frame without generating the optical flow reference frame; and the current block is decoded based on the optical flow reference block.
-
-
-
-
-
-
-
-
-