Huawei Technologies Co., Limited

Future Wei Technologies, Inc.

Huawei Technologies,co., Ltd.

Vasily Alexeevich Rufitskiy

Alexey Konstantinovich Filippov

Jianle Chen

Elena Alexandrovna Alshina

Haitao Yang

Semih Esenlik

Huanbang Chen

Alexander Alexandrovich Karabutov

Biao Wang

Han Gao

Shan Liu

Timofey Mikhailovich Solovyev

Maxim Borisovitch Sychev

Xiang Ma

An intra-prediction apparatus and method are provided for extending a set of predetermined directional intra-prediction modes of a rectangular video coding block. The intra-prediction apparatus determines an aspect ratio of the rectangular video coding block, and determines a complementary angle range based on the aspect ratio. The apparatus then selects a complementary direction within the complementary directional range, and adds an extension directional intra-prediction mode associated with the complementary direction to the set of predetermined directional intra-prediction modes. Based on the extension directional intra-prediction mode, the apparatus intra-predicts pixel values of pixels of the rectangular video coding block.

Intra-prediction apparatus for extending a set of predetermined directional intra-prediction modes

The present invention relates to method and apparatus for motion vector derivation for affine based inter prediction of chroma subblocks based on chroma format. The method includes: determining chroma scaling factors in horizontal and vertical directions based on chroma format information, wherein the chroma format information indicates a chroma format of a current picture which the current image block belongs to; determining a set (S) of luma subblocks of the luma block based on values of the chroma scaling factors; determining a motion vector for a chroma subblock of the chroma block based on motion vectors of one or more luma subblocks in the set (S) of luma subblocks.

Method and apparatus for affine based inter prediction of chroma subblocks

Devices and methods of directional intra prediction for chroma component of a picture are provided. The method includes obtaining an initial intra prediction mode of the chroma component based on a value of a luma intra prediction mode (intraPredModeY) by using a first look up table (LUT), deriving a chroma intra prediction mode (intraPredModeC) from a second LUT by using the initial intra prediction mode of the chroma component. The chroma component has different subsampling ratios in horizontal and vertical directions. The second LUT has 67 entries, indices for the second LUT are 0-66, and each index is associated with an angle of an intra prediction direction. The method further includes obtaining an angle parameter for the chroma component based on the chroma intra prediction mode intraPredModeC; and obtaining predicted samples of the chroma component based on the angle parameter.

Method and apparatus for chroma intra prediction in video coding

A method for intra prediction is provided, the method including: obtaining a predicted sample value for a sample of the block; obtaining a scaling factor value according to an intra prediction mode for the current coding block, and according to at least one of: a height of the current coding block, or a width of the current coding block, or a size of a subpartition of the current coding block; determining a first weight value based on the scaling factor value; determining a second weight value based on the scaling factor value; calculating an additional value as a weighted sum of a top reference sample value and a left reference sample value, by weighting the top reference sample value with the first weight and the left reference sample value with the second weight; and obtaining a modified predicted sample value according to the additional value and the predicted sample value.

Method and apparatus for intra prediction

A video coding device, comprising a sequence of filters that are configurable by one or more primary parameters and one or more secondary parameters, and a filter controller configured to adjust the one or more secondary parameters based on the one or more primary parameters and based on a strength criterion of the sequence of filters.

Method and apparatus for video coding

An inter prediction method includes determining whether a non-rectangular inter prediction mode is allowed for a group of blocks; obtaining one or more inter prediction mode parameters and weighted prediction parameters for the group of blocks; and obtaining prediction value of a current block based on the one or more inter prediction mode parameters and weighted prediction parameters, wherein one of the inter prediction mode parameters indicates reference picture information for the current block, and wherein the group of blocks comprises the current block.

Method and apparatus of harmonizing weighted prediction with non-rectangular merge modes

The present disclosure relates to intra- or inter-prediction for video encoding and decoding. For that purpose, an apparatus and methods obtain a reference sample and a subpixel offset value. A 4-tap interpolation filter is used to filter the reference sample to obtain a predicted sample value. The filter coefficients c, c, c, and cof the 4-tap interpolation filter satisfy with p being a fractional part of the value of the subpixel offset.

Method and apparatus of interpolation filtering for predictive coding

A method for intra prediction of a current block of a picture is provided. The method includes obtaining an aspect ratio of the current block according to a width and a height of the current block; obtaining a weighting factor based on the aspect ratio, and determining an intra-prediction value of the current block based on the weighting factor. Intra-prediction value of a current block may be obtained with high accuracy or low computational complexity, so as to improve coding efficiency.

Method and apparatus for DC intra prediction of rectangular blocks using an aspect ratio

A method for an intra predicting process of a video block is provided. The method comprises: obtaining a predicted sample value for a sample of the current coding block; obtaining a scaling factor value according to an intra prediction mode for the current coding block, and according to a height of the current coding block and/or a width of the current coding block; determining a first weight based on the scaling factor value; determining a second weight based on the scaling factor value; calculating an additional value as a weighted sum of a top reference sample value and a left reference sample value, by weighting the top reference sample value with the first weight and weighting the left reference sample value with the second weight; obtaining a modified predicted sample value according to the additional value and the predicted sample value; and outputting the modified predicted sample.

Prediction combination for oblique directional intra prediction

A method includes: obtaining one or more parameters of a geometric merge (GEO) inter prediction mode for a current coding block; defining a size of a subblock that is smaller than a size of the current coding block; specifying a position of the subblock within the current coding block, so that either two or three sides of the subblock coincide with sides of the current coding block; determining one or more allowed split directions of a triangle partitioning mode (TPM) for the subblock depending on which of the sides of the subblock coincide with the sides of the current coding block; and obtaining one or more predicted samples for the current coding block by using the TPM partitioning performed for the subblock in accordance with the size of the subblock, the position of the subblock within the current coding block and a TPM split direction of the subblock.

Method and apparatus of simplified geometric merge mode for inter prediction

Intra- or inter-prediction can be used for video encoding and decoding. For that purpose, an apparatus and methods obtain a filter (a set of coefficients) from a set of filters based on the subsample position (p) defined for the set of positions of predicted samples, where the set of filters is obtained by combining at least two pre-defined input filter sets.

Method and apparatus of subsample interpolation filtering

The disclosure relates to methods and a coding apparatus for intra prediction using a linear model. The method includes: determining a filter for a luma component of a current block based on a chroma format of a picture that the current block belongs to, and applying the determined filter to an area of reconstructed luma samples of the luma component of the current block and/or luma samples in selected position neighboring to the current block, to obtain filtered reconstructed luma samples. The method further includes: obtaining, based on the filtered reconstructed luma samples, linear model coefficients. Cross-component prediction is performed based on linear model coefficients of the linear model derivation and the filtered reconstructed luma sample.

Method and apparatus of filtering for cross-component linear model prediction

The present disclosure relates to moving picture processing, and in particular, to cases where non-rectangular partitioning modes are used for inter-prediction in a combination with weighted prediction (WP) for coding fades. Non-rectangular modes refer to those inter-prediction modes, in which case a current block is partitioned/sliced in a non-rectangular way (slices). Such modes may be triangular (TMP) or geometric (GEO) prediction. The aim of the disclosure is to harmonize non-rectangular partitioning modes with WP by way of disabling TMP/GEO when WP is applied. This may be accomplished by checking whether all reference pictures for a current slice are disabled, and if this is the case to disable the slice-level WP for non-rectangular prediction units. Whether the reference pictures are disabled may be determined based on conditions applied on set values, for example, of luma/chroma flags, which refer to the reference pictures.

Method and apparatus of harmonizing triangular merge mode with weighted prediction

The present application relates to the field of picture processing, for example still picture/image and/or video picture/image coding. In particular, the application relates to a device and corresponding method for intra-predicting a prediction block of a video image. The device is configured to select a directional intra-prediction mode from a set of directional intra-prediction modes, where each directional intra-prediction mode corresponds to a different intra-prediction angle. Further, the device is configured to select a filter from a set of filters based on the selected directional intra-prediction mode. Further, the device is configured to determine, for a prediction sample of the prediction block, a reference sample from a set of reference samples based on the selected directional intra-prediction mode, and apply the selected filter to the determined reference sample.

Device and method for intra-prediction

A method of intra prediction of a coding block, performed by a decoder, the method comprising: obtaining a bitstream for the coding block; obtaining a value of intra prediction mode according to the bitstream; obtaining a value of an index for the coding block in accordance with the bitstream; obtaining a set of reference samples for the coding block, the set of reference samples comprises samples of a reconstructed block and additional samples; when the value of the index for the coding block is not equal to the predefined value, the set of reference samples comprises only of samples of the reconstructed block; obtaining a prediction value of a sample comprised in the coding block, according to the value of intra prediction mode for the coding block and the set of reference samples.

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Moscow, Russia

Vasily Alexeevich Rufitskiy