Abstract:
A method and apparatus for coding video data in a scalable or three-dimensional video coding system are disclosed. In one embodiment, context for the input data associated with an inter-layer or inter-view coding syntax element of a current block in an enhancement-layer (EL) or a dependent view is formed or the input data is parsed to identify the context based on information associated with one or more neighboring blocks, information associated with the current block, or both. In another embodiment, encoding or decoding is applied to the input data associated with the current block in the EL using inter-layer texture prediction based on the BL block in the BL, wherein a flag indicating whether there is any transform coefficient coded for the current block is signaled.
Abstract:
Aspects of the disclosure provide a method for denoising a reconstructed picture. The method can include receiving reconstructed video data corresponding to a picture, dividing the picture into current patches, forming patch groups each including a current patch and a number of reference patches that are similar to the current patch, denoising the patch groups to modify pixel values of the patch groups to create a filtered picture, and generating a reference picture based on the filtered picture for encoding or decoding a picture. The operation of denoising the patch groups includes deriving a variance of compression noise in the respective patch group based on a compression noise model. A selection of model parameters is determined based on coding unit level information.
Abstract:
A method for color index coding of blocks in a picture is disclosed. In one embodiment for the decoder side, a current coding mode is parsed from the input coded bitstream for one or more first currently decoded pixels in a current block starting from a first starting position. If the current coding mode corresponds to a generalized copy-previous-row mode, one or more first reference pixels starting from a first starting reference position located at T-th row above the first currently decoded pixels are identified, where T is an integer equal to or greater than one. The first reference pixels starting from the first starting reference position are then used to decode the first currently decoded pixels starting from a first starting position by copying the first reference pixels starting from the first starting reference position respectively. The system may also include a copy-left mode or escape mode.
Abstract:
A method and apparatus of video coding using IntraBC (Intra Block Copy) for video data are disclosed. Restricted prediction is determined, in which one or more selected PU (prediction unit) sizes, PU prediction types or both are disabled or disallowed. Video coding is applied to the current block using coding modes including IntraBC prediction in accordance with the restricted prediction. The selected PU sizes, PU prediction types or both may correspond to 8×8 bi-prediction PU. In one example, the selected PU sizes, PU prediction types or both are disabled or disallowed for the restricted prediction except one or more conditions are determined to be satisfied. The conditions may correspond to at least one of two motion vectors of the 8×8 bi-prediction PU having integer values, the conditions may also correspond to at least one of motion vector components of the 8×8 bi-prediction PU having integer valueIntraBCIntraBCIntraBCIntraBCIntraBC.
Abstract:
A video codec that encodes or decodes video sequences using decoder-side motion vector refinement is provided. The video codec identifies a first motion vector and a second motion vector for coding a current block of pixels of a current video frame in the video sequence. The video codec determines whether to perform motion vector refinement for the current block of pixels based on a comparison between a linear dimension of the current block of pixels and a threshold. When motion vector refinement is performed, the video codec refines the first and second motion vectors to minimize a distortion cost and codes the current block of pixels by using the refined first and second motion vectors. When motion vector refinement is not performed, the video codec codes the current block of pixels by using the identified first and second motion vectors.
Abstract:
In order to overcome the issue caused by a decoded block vector (BV) pointing to a reference block overlapping with an unavailable area, various methods are disclosed. According to one method, if the reference block overlaps with an unavailable area, the reference pixels in the unavailable area are generated for IntraBC prediction of the current block by padding from neighboring available pixels. The padding can be done in the horizontal direction and then the vertical direction. The padding may also done in the vertical direction first and then horizontal direction. In another method, if the reference block overlaps with an unavailable area, the reference pixels in the unavailable area are generated for IntraBC prediction of the current block by using previous decoded pixels in the unavailable area. A pre-defined value may also be used for the unavailable area.
Abstract:
Methods of adaptive transform type based on transform unit (TU) size for enhancement layer (EL) coding and multiple motion candidates for EL coding based on corresponding base layer (BL) video data are provided. One method selects a transform type from multiple allowable transform types based on the TU size and applies the selected transform type to the transform units of the inter-layer prediction processed data. Another method derives multiple motion candidates for the EL video data coded in Merge mode or Inter mode based on motion information associated with the corresponding BL video data.
Abstract:
Concepts and examples pertaining to coding unit information inheritance are described. A processor of an encoder may receive media contents and encode the media contents to provide a bitstream of encoded media contents. A processor of a decoder may receive the bitstream of encoded media contents and decode the bitstream to provide one or more streams of decoded media contents. The bitstream may include information indicating coding unit (CU) information inheritance that is used by a decoder in conjunction with quad-tree (QT) partition and binary-tree (BT) partition to achieve asymmetric or triple-tree (TT) partition of a CU.
Abstract:
Methods and apparatus for image or video decoding in a video decoding system are disclosed. Input data associated with a current block coded with palette mode is received to parse a palette predictor run. A position of reused colors in a palette predictor table is computed according to the palette predictor run. A size of the palette predictor table is determined and compared with the position computed according to the palette predictor run to obtain a comparison result. The decoder applies palette decoding to the current block according to the comparison result. If the comparison result indicates the position computed according to the palette predictor run is not within the palette predictor table, the position is changed to a new position to indicate a corresponding reused color for the current block or a decoding process of palette predictor reuse flags is terminated.
Abstract:
Method and apparatus for coding a block of video data using palette coding in a video coding are disclosed. According to one embodiment, whether there is only one single palette index in the current block is determined first. If there is only one single palette index in the current block, signaling a current palette index map for the current block is omitted at an encoder side or parsing any syntax for decoding the current palette index map for the current block is omitted at a decoder side. The decision regarding whether there is only one single palette index in the current block is based on one or more syntax elements not corresponding to palette index coding.