-
1.发明申请公开(公告)号：WO2019099084A1
公开(公告)日：2019-05-23
申请号：PCT/US2018/047223
申请日：2018-08-21
Applicant: GOOGLE LLC
Inventor： XU, Yaowu , HAN, Jingning , CHIANG, Ching-Han
IPC: H04N19/176 , H04N19/70 , H04N19/147 , H04N19/567 , H04N19/577 , H04N19/51
CPC classification number: H04N19/573 , H04N19/147 , H04N19/176 , H04N19/182 , H04N19/44 , H04N19/51 , H04N19/567 , H04N19/577 , H04N19/70
Abstract: A motion-field based reference frame is rendered that can be used to perform a prediction process for a first frame of a video sequence to be predicted. A first reference frame from the video sequence for forward inter prediction of the first frame is determined, as is a second reference frame from the video sequence for backward inter prediction of the first frame. A respective motion field determined for blocks of the first frame is used to determine parameters forming an affine homographic model. A current block of a reconstructed reference frame is rendered at a co-located position within a motion field-based reference frame by applying the affine homographic model to the current block. An affine homographic model may be determined for each reconstructed reference frame block to render the motion-field based reference frame.
-
公开(公告)号：WO2019013842A1
公开(公告)日：2019-01-17
申请号：PCT/US2018/022794
申请日：2018-03-16
Applicant: GOOGLE LLC
Inventor： CHIANG, Ching-Han , HAN, Jingning , XU, Yaowu
Abstract: Video syntax elements are coded using a context tree. Context information used for coding previously-coded syntax elements is identified. A context tree is produced by separating the previously-coded syntax elements into data groups based on the context information. The context tree includes nodes representing the data groups. Separating the previously-coded syntax elements can include applying separation criteria against values of the context information to produce at least some of the nodes. Context information is then identified for another set of syntax elements to be coded. One of the nodes of the context tree is identified based on values of the context information associated with one of the other set of syntax elements. That syntax element is then coded according to a probability model associated with the identified node. The context tree can be used to encode or decode syntax elements.
-
公开(公告)号：WO2018160231A1
公开(公告)日：2018-09-07
申请号：PCT/US2017/059272
申请日：2017-10-31
Applicant: GOOGLE LLC
Inventor： XU, Yaowu , HAN, Jingning , CHIANG, Ching-Han
IPC: H04N19/463 , H04N19/12 , H04N19/137 , H04N19/176
Abstract: Transform kernel candidates including a vertical transform type associated with a vertical motion and a horizontal transform type associated with a horizontal motion can be encoded or decoded. During an encoding operation, a residual block of a current block is transformed according to a selected transform kernel candidate to produce a transform block. A probability model for encoding the selected transform kernel candidate is then identified based on neighbor transform blocks of the transform block. The selected transform kernel candidate is then encoded according to the probability model. During a decoding operation, the encoded transform kernel candidate is decoded using the probability model. The encoded transform block is then decoded by inverse transforming dequantized transform coefficients thereof according to the decoded transform kernel candidate.
-
公开(公告)号：WO2018048516A1
公开(公告)日：2018-03-15
申请号：PCT/US2017/044639
申请日：2017-07-31
Applicant: GOOGLE LLC
Inventor： HAN, Jingning , CHIANG, Ching-Han
IPC: H04N19/176 , H04N19/134 , H04N19/129 , H04N19/60 , H04N19/136 , H04N19/18 , H04N19/192
Abstract: Video coding using a context adaptive scan order for entropy coding may include decoding a current block by identifying a context adaptive scan order for entropy decoding a transform block, which may include identifying non-zero-coefficient probabilities for the transform block such that each location in the transform block corresponds to a respective non-zero-coefficient probability from the non-zero-coefficient probabilities, assigning a respective context adaptive scan order position to each location in the transform block in descending magnitude order of the respective corresponding non-zero-coefficient probabilities such that the context adaptive scan order position for each location exceeds the context adaptive scan order position assigned to entropy coding context locations for the respective location, entropy decoding transform coefficients from the encoded video stream based on the context adaptive scan order, and reconstructing the decoded block based on the transform block.
Abstract translation: 使用用于熵译码的上下文自适应扫描次序的视频译码可包含通过识别用于对变换块进行熵译码的上下文自适应扫描次序来解码当前块，所述上下文自适应扫描次序可包括将用于熵解码的非零系数概率 所述变换块使得所述变换块中的每个位置对应于来自所述非零系数概率的相应的非零系数概率;以相应的上下文自适应扫描顺序位置向所述变换块中的每个位置分配按照 各个对应的非零系数概率使得每个位置的上下文自适应扫描次序位置超过分配给各个位置的熵译码上下文位置的上下文自适应扫描次序位置，基于所述编码视频流对来自编码视频流的变换系数进行熵解码 上下文自适应扫描顺序，并且基于tra重建解码块 nsform block。
-
公开(公告)号：WO2019152570A9
公开(公告)日：2019-08-08
申请号：PCT/US2019/015930
申请日：2019-01-30
Applicant: GOOGLE LLC
Inventor： HAN, Jingning , ZERN, James , ZHANG, Linfeng , CHIANG, Ching-Han , XU, Yaowu
IPC: H04N19/13 , H04N19/70 , H04N19/423
Abstract: Coding a transform block using level maps is disclosed. A method includes determining a lower plane of values, processing the lower plane in a reverse scan order, and selecting a template for entropy-coding the values of the lower plane. The method also includes, for a current value of the lower plane, selecting, based on the template anti-diagonal lines, two or more line buffers, each of the two or more line buffers corresponding to a respective scan-order anti-diagonal line, determining a context using the two or more line buffers, and entropy encoding the current value using the context. Each value is a respective "up-to" value of a transform coefficient. The reverse scan order visits the values of the lower plane along scan-order anti-diagonal lines. The template indicates scan positions of coded values of the lower plane, the scan positions are arranged, in the template, along template anti-diagonal lines.
-
公开(公告)号：WO2018140108A1
公开(公告)日：2018-08-02
申请号：PCT/US2017/059246
申请日：2017-10-31
Applicant: GOOGLE LLC
Inventor： XU, Yaowu , HAN, Jingning , CHIANG, Ching-Han
IPC: H04N19/70 , H04N19/13 , H04N19/91 , H04N19/157 , H04N19/18
CPC classification number: H04N19/60 , G06K9/00362 , G06K9/00624 , G06K9/00711 , G06K9/00771 , G06K9/00778 , G08B13/19602 , G08B13/19604 , H04N5/23238 , H04N19/129 , H04N19/13 , H04N19/157 , H04N19/18 , H04N19/44 , H04N19/48 , H04N19/645 , H04N19/70 , H04N19/88 , H04N19/91
Abstract: A method for encoding a transform block in an encoded video bitstream includes encoding a non-zero map indicating positions of the transform block containing non-zero transform coefficients, encoding a respective lower-range level map, and encoding a coefficient residual map. A lower-range level map indicates which values of the non-zero transform coefficients are equal to and which are greater than the map level. Each residual coefficient of the coefficient residual map corresponds to a respective non-zero transform coefficient of the transform block having an absolute value exceeding the maximum map level. An apparatus including a processor and a memory for decoding a transform block is also provided. The memory includes instructions executable by the processor to decode, a non-zero map, decode lower-range level maps up to a maximum map level, and decode a coefficient residual map.
-
公开(公告)号：WO2019152570A1
公开(公告)日：2019-08-08
申请号：PCT/US2019/015930
申请日：2019-01-30
Applicant: GOOGLE LLC
Inventor： HAN, Jingning , ZERN, James , ZHANG, Linfeng , CHIANG, Ching-Han , XU, Yaowu
IPC: H04N19/13 , H04N19/70 , H04N19/423
Abstract: Coding a transform block using level maps is disclosed. A method includes determining a lower plane of values, processing the lower plane in a reverse scan order, and selecting a template for entropy-coding the values of the lower plane. The method also includes, for a current value of the lower plane, selecting, based on the template anti-diagonal lines, two or more line buffers, each of the two or more line buffers corresponding to a respective scan-order anti-diagonal line, determining a context using the two or more line buffers, and entropy encoding the current value using the context. Each value is a respective "up-to" value of a transform coefficient. The reverse scan order visits the values of the lower plane along scan-order anti-diagonal lines. The template indicates scan positions of coded values of the lower plane, the scan positions are arranged, in the template, along template anti-diagonal lines.
-
公开(公告)号：WO2019036077A1
公开(公告)日：2019-02-21
申请号：PCT/US2018/031234
申请日：2018-05-04
Applicant: GOOGLE LLC
Inventor： CHIANG, Ching-Han , HAN, Jingning , XU, Yaowu , FENG, Jia
IPC: H04N19/129 , H04N19/91 , H04N19/156 , H04N19/18 , H04N19/423
Abstract: A method for coding a transform block of coefficients includes generating a new scan order from the original scan order such that a maximum scan distance of the new scan order is smaller than or equal to a predetermined distance, and coding the coefficients based on the new scan order. An apparatus for decoding a transform block of coefficients includes a memory and a processor. The memory includes instructions executable by the processor to identify an original scan order for encoding the coefficients, generate a new scan order from the original scan order such that a maximum scan distance of the new scan order is less than or equal to a predetermined distance, and decode, from an encoded bitstream, the coefficients based on the new scan order.
-
公开(公告)号：WO2018136128A1
公开(公告)日：2018-07-26
申请号：PCT/US2017/059241
申请日：2017-10-31
Applicant: GOOGLE LLC
Inventor： XU, Yaowu , HAN, Jingning , CHIANG, Ching-Han
Abstract: A sign value of a DC coefficient of a current block is determined using neighbor blocks of the current block. First and second sign values are identified as respectively corresponding to an above neighbor block of the current block and a left neighbor block of the current block. A context value is calculated by applying a first weighting value to the first sign value and a second weighting value to the second sign value. The first weighting value is based on a boundary between the above neighbor block and the current block, and the second weighting value is based on a boundary between the left neighbor block and the current block. A probability value is selected based on the context value. The sign value of the DC coefficient of the current block is then determined using the probability model.
