Hfi Innovation Inc.

Mediatek Corporation

Mediatek Singapore Pte. Ltd.

Microsoft Technology Licensing, LLC

Xun Guo

Shaw-Min Lei

Yu-Wen Huang

Mei Guo

Jicheng An

Liang Zhao

Xin Zhao

Chih-Wei Hsu

Chih-Ming Fu

Qian Huang

Shipeng Li

Yan Lu

Feng Wu

Yu Wang

Xinfeng Zhang

Juliana Hsu

Si-Wei Ma

Kai Zhang

A method and apparatus for intra prediction for a current block using directional intra prediction based on neighboring pixels around the current block are disclosed. Embodiment according to the present invention derives the gradient for the current pixel from the neighboring reconstructed pixels along a prediction direction of directional intra prediction. The gradient derived is used to form the final intra prediction. In another embodiment of the present invention, the intra prediction for slant vertical and horizontal directions is derived based on the neighboring reconstructed pixels in a neighboring row adjacent to the top side of the current block and the neighboring reconstructed pixels in a neighboring column adjacent to the left side of the current block.

Method and apparatus of directional intra prediction

A method includes receiving the video bitstream from a media or a processor, recovering a first coded block flag (cbf) from the video bitstream based on a context-based adaptive binary arithmetic coding (CABAC) decoding process according to a first context formation, wherein the first cbf is associated with a first transform unit (TU) of a first color component, and the first cbf indicates whether the first TU of the first color component has at least one non-zero transform coefficient, and recovering a second cbf from the video bitstream based on the CABAC decoding process according to a second context formation, wherein the second cbf is associated with a second TU of a second color component, and the second cbf indicates whether the second TU of the second color component has at least one non-zero transform coefficient.

Method and apparatus for coded block flag coding in high efficiency video coding

The present disclosure describes a method of decoding a block, and the method includes receiving a flag indicating whether a current intra prediction mode is equal to any of one or more most probable modes, deriving, based on a value of the flag, the current intra prediction mode from a decoded mode index, and decoding the block according to the current intra prediction mode. The current intra prediction mode belongs to a mode set that includes a DC mode, a Planar mode, and at least one directional mode. The deriving the current intra prediction mode includes, when the mode index corresponds to a first mode index value representing the Planar mode, deriving the current intra prediction mode to be the Planar mode; and, when the mode index corresponds to a second mode index value representing the DC mode, deriving the current intra prediction mode to be the DC mode.

Method and apparatus of intra mode coding

An encoder for receiving a video frame and performing encoding processes to generate an encoded bitstream includes: a fidelity enhancement block, for performing a fidelity enhancement technique on processed data utilizing a partition method, and generating fidelity enhancement information comprising at least one parameter associated with a partition structure, wherein the fidelity enhancement technique comprises applying discrepancy modeling based on DC offset; and an entropy coding block, coupled to the fidelity enhancement block, for encoding the fidelity enhancement information, and embedding the encoded fidelity enhancement information into the encoded bitstream.

In-loop fidelity enhancement for video compression

Method and apparatus for intra prediction mode coding and decoding are disclosed. In one embodiment, the encoding and decoding process assigns individual indices and codewords to DC mode and Planar mode respectively. The flag is set if the current intra prediction mode is equal to any of one or more neighboring intra prediction modes. Variable length codes are designed for a remaining mode set. If the flag is not set, the currently intra prediction mode is encoded using the variable length codes. In another embodiment, multiple most probable modes are used. If the current intra prediction mode is not equal to any of the multiple most probable modes, the current intra prediction mode is encoded using variable length codes designed for the corresponding remaining modes according the ranking order of the remaining modes.

A method for performing parallel coding with ordered entropy slices includes: providing a plurality of entropy slices to a plurality of processing elements, wherein each entropy slice includes a plurality of blocks; initializing CABAC states of a current entropy slice as the CABAC states of a previous entropy slice after processing Dblocks of the previous entropy slice. Dis a positive integer.

Method for performing parallel coding with ordered entropy slices, and associated apparatus

A method and apparatus for deblocking reconstructed video in a video coding system. The method receives reconstructed pixel data, wherein the reconstructed pixel data is configured into LCUs (largest coding units) and each LCU is divided into blocks. The method then identifies horizontal block edges of the blocks in the LCUs, applies first vertical filtering to the reconstructed pixel data corresponding to one or more first lines above a first horizontal block edge in the first edge group, and applies second vertical filtering to the reconstructed pixel data corresponding to one or more second lines above a second horizontal block edge in the second edge group, wherein a first number of said one or more first lines is smaller than a second number of said one or more second lines.

Method and apparatus for reduction of deblocking filter

A method and an apparatus for decoding of a video bitstream are disclosed. In one embodiment, the method comprises: decoding a first coded block flag (cbf) of the color component indicating whether a current coding unit (CU) of the color component has at least one non-zero transform coefficient (). According to the first cbf of the color component, the method further comprises decoding four second cbfs, each indicating whether one of four sub-blocks in the current CU of the color component has at least one non-zero transform coefficient (). The residual quad-tree (RQT) of the current CU of the color component is determined based on the first cbf of the color component (), or based on the first cbf and the second cbfs of the color component if the second cbfs exist (). In another embodiment, the method comprises decoding a cbf associated with a transform unit (TU) and determining RQT of the TU based on the cbf, wherein said determining the RQT of the TU based on the cbf is the same for a luma component and a chroma component and the cbf is recovered from the video bitstream.

A method and apparatus for deriving a motion vector predictor (MVP) candidate set for motion vector coding of a current block. Embodiments according to the present invention determine a redundancy-removed spatial-temporal MVP candidate set. The redundancy-removed spatial-temporal MVP candidate set is derived from a spatial-temporal MVP candidate set by removing any redundant MVP candidate. The spatial-temporal MVP candidate set includes a top spatial MVP candidate, a left spatial MVP candidate and one temporal MVP candidate. The method further checks whether candidate number of the redundancy-removed spatial-temporal MVP candidate set is smaller than a threshold, and adds a zero motion vector to the redundancy-removed spatial-temporal MVP candidate set if the candidate number is smaller than the threshold. Finally, the method provides the redundancy-removed spatial-temporal MVP candidate set for encoding or decoding of the motion vector of a current block.

Method and apparatus for simplified motion vector predictor derivation

A method and apparatus for deblocking of reconstructed video in a video coding system are disclosed. Embodiments according to the present invention determine boundary strength between two blocks without checking whether the block boundary is a coding unit (CU) boundary. In one embodiment according to the present invention, the method comprises determining whether any of the two blocks is Intra coded. If any of the two blocks is Intra coded, the boundary strength is assigned a first value. Otherwise, additional decision processing is performed to determine the boundary strength. In another embodiment, said determining the boundary strength for the block boundary comprises determining whether the block boundary is a TU boundary and whether any of the two blocks contains coefficients. In yet another embodiment, said determining the boundary strength for the block boundary comprises determining whether the two blocks have different reference pictures or different motion vectors.

Method and apparatus of deblocking filter with simplified boundary strength decision

A method and apparatus for deriving a motion vector predictor (MVP) candidate set for motion vector coding of a current block. Embodiments according to the present invention determine a redundancy-removed spatial MVP candidate set by removing any redundant MVP candidate from the spatial MVP candidate set. The redundancy-removal process does not apply to the temporal MVP candidate. In another embodiment of the present invention, a redundancy-removed spatial-temporal MVP candidate set is determined and the number of candidates in the redundancy-removed spatial-temporal MVP candidate set is checked to determine whether it is smaller than a threshold. If the number of candidates is smaller than the threshold, a zero motion vector is added to the redundancy-removed spatial-temporal MVP candidate set. The redundancy-removed spatial-temporal MVP candidate set is then provided for encoding or decoding of the motion vector of the current block.

A method and apparatus for chroma intra prediction is based on reconstructed luma pixels and chroma pixels, where the chroma intra prediction is based on a linear model of derived co-located current luma pixels of the current luma block scaled by a scaling factor. The scaling factor comprises a product term of a division factor and a scaled covariance-like value associated with neighboring reconstructed luma and chroma pixels of a current block. The division factor is related to a first data range divided with rounding by a scaled variance-like value associated with the neighboring reconstructed luma pixels of the current block. The scaled covariance-like value, the first data range, or both of the scaled covariance-like value and the first data range are dependent on the internal bit depth, with which the chroma signal is processed during video coding process, according to an embodiment of the present invention.

Method and apparatus of simplified luma-based chroma intra prediction

A video encoder that utilizes adaptive interpolation filtering for coding video data includes a prediction unit, a reconstruction unit, a reference picture buffer, a filter parameter estimator for estimating filter parameters according to the original video data and the predicted samples, and an adaptive interpolation filter for utilizing the stored filter parameters to perform filtering on the reconstructed video data.

Adaptive interpolation filter for video coding

A method and apparatus for clipping a transform coefficient are disclosed. In one implementation, a method is implemented in a video encoder for clipping a quantization level. The method operates by generating the quantization level for a transform coefficient of a transform unit by quantizing the transform coefficient according to a quantization matrix and quantization parameter, determining a clipping range in the video encoder for one or a combination of a fixed-range clipping condition and a dynamic-range clipping condition, and clipping the quantization level according to the clipping range to generate a clipping-processed quantization level. The quantization level is clipped within a fixed clipping range from &#x2212;m to m&#x2212;1 for the fixed-range clipping condition and m corresponds to 128, 32768, or 2147483648.

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Beijing, China

Xun Guo