Abstract: A filter, to an encoder and a decoder using the filter, to a filtering method and a corresponding program, as well as to encoding and decoding using the filtering method or the filter. The method includes obtaining of an extended reconstructed block by extending the current reconstructed block to include at least padding samples from the current reconstructed block. After padding, a current pixel of the extended reconstructed block and its neighboring pixels are loaded into a linear buffer and transformed with a one-dimensional (1D) transform. The method is performed in frequency domain using a look-up table and the filtered pixels are transformed back.

Abstract: A method of obtaining quantization parameter (QP) for chrominance components based on QP for luminance component, wherein the method is performed by a decoder or encoder, and wherein the method comprises obtaining a luminance QP for a luma component of a coding unit; obtaining a QP index (QPi) based at least in a part on the luminance QP; and obtaining a chrominance QP (QPc) for a chroma component of the coding unit based on the QP index by using a preset lookup table, wherein the maximum difference between the QP index and the chrominance QP is equal to 3.

Abstract: A method of obtaining a chrominance quantization parameter (QP) for chrominance components based on a luminance QP for a luminance component, wherein the method is performed by a decoder, and comprises parsing a received bitstream to obtain the luminance QP and information of a mapping function (ƒ) which associates a QP index (QPi) to a chrominance QP (QPc); obtaining the QPi based at least in part on the luminance QP; obtaining the mapping function based on the obtained information of the mapping function; and obtaining a QPc based on the obtained mapping function and the obtained QPi.

Abstract: A method of obtaining a chrominance quantization parameter (QP) for chrominance components based on a luminance QP for luminance component, wherein the method is performed by a decoder, comprising parsing a received bitstream to obtain the luminance QP and information of a mapping function (ƒ) which associates a QP index (QPi) to the chrominance QP (QPc); obtaining the QPi based at least in a part on the luminance QP; obtaining the mapping function based on the obtained information; and obtaining a QPc based on the obtained mapping function and the obtained QPi.

Abstract: The present invention relates to an improved apparatus and method for harmonizing both Sign Bit Hiding (SBH) and Residual Sign Prediction (RSP) techniques in video coding. In order to improve coding efficiency, a list of transform coefficients, to which RSP is to be applied is prepared in advance of selecting a coefficient to which SBH is applied. Thereby, the RSP list can be populated in such a manner that the highest coding efficiency may be expected. Subsequently, one or more coefficients for applying SBH are selected so as not to be included in the list.

Abstract: A picture encoding apparatus configured to hierarchically partition a block of picture data into sub-blocks; determine that a sub-block being coded belongs to an unequally-sized partitioned block; prepare a list of neighboring blocks for the sub-block of the unequally-sized partitioned block based on a size of the sub-block of the unequally-sized partitioned block and a partitioning type of at least one neighboring block of the unequally-sized partitioned block; and derive a context model that is used to encode split information of the sub-block of the unequally-sized partitioned block into a bit stream based on the prepared list of neighboring blocks.

Abstract: The present disclosure relates to video encoding and decoding, and in particular, a method for inter prediction for a block in a frame of a video signal includes: constructing a history-based motion information candidate list, wherein the list is an ordered list comprising N history-based motion information candidates Hk containing motion information of N preceding blocks preceding the block, wherein each history-based motion information candidate comprises elements: one or more motion vectors (MVs), one or more reference picture indices corresponding to the MVs, and an interpolation filter index; adding one or more history-based motion information candidates from the history-based motion information candidate list into a motion information candidate list for the block; and deriving motion information for the block based on the motion information candidate list.

Abstract: A system and method for improving quality of encoding and decoding a panoramic video. The panoramic video comprises a sequence of encoded picture frames. In panoramic video picture frames are mapped on a spherical viewing area. In the method the projection center of the encoded frame is transformed before encoding. In the decoding phase the projection center is transformed back accordingly after decoding the frame.

Abstract: An apparatus and method for inter prediction of a block includes estimating local illumination compensation (LIC) parameters using first reference samples of a current block and second reference samples of a reference block, wherein a third reference sample of the second reference samples is based on an integer part of a fractional motion vector (MV), and obtaining inter prediction of the current block according to the LIC parameters.

Abstract: A method of determining a distance table of a merge with motion vector difference (MMVD) mode, wherein the method comprises determining a reference picture from at least one reference picture list of a current processing unit based on at least one parameter of the reference picture, and obtaining the distance table for the current processing unit based on the reference picture, wherein the at least one parameter of the reference picture comprises a picture order count (POC) number of the reference picture, a number of MMVD blocks of the reference picture, a reference picture list index of the reference picture, a reference picture index of the reference picture, and a quantization parameter (QP) of the reference picture.

Abstract: The disclosure provides a motion vector compression method, comprising: obtaining a temporal motion vector; determining a compressed motion vector using a binary representation of the temporal motion vector comprising an exponent part and/or a mantissa part, wherein the exponent part comprises N bits, the mantissa part comprises M bits, and wherein N is a non-negative integer and M is a positive integer; and performing a temporal motion vector prediction (TMVP) using the compressed motion vector.

Abstract: A method for inverse quantization of a current block of a picture is performed by a decoder, and the picture comprises a luminance component and a chrominance component, wherein the luminance component and the chrominance component are partitioned into multiple blocks. The method includes: obtaining one or more existing quantization parameter (QP) values from a received bitstream, wherein the one or more existing QP values relate to a current block in the chrominance component; determining a QP value for the current block in the chrominance component based on the one or more existing QP values; and performing inverse quantization on the current block in the chrominance component by using the determined QP value.

Abstract: A prediction method for an image block comprising a first prediction sub-block and a second prediction sub-block, the prediction method comprising: parsing a first index from a bitstream, wherein the first index is used to obtain prediction information of the first prediction sub-block; parsing a second index from the bitstream; comparing the first index with the second index; adjusting the second index in the event that the second index is equal to or greater than the first index; and obtaining prediction information of the second prediction sub-block according to the adjusted second index.

Abstract: The present disclosure relates to methods and apparatuses for encoding video data into a bitstream and for decoding video data received in a bitstream. A second control flag indicating whether or not to use multi-hypothesis prediction for intra and inter mode is generated and transmitted only conditionally, upon a determination whether or not separate merge list technique for subblock merge candidates is used. On the other hand, a decoder is capable of deciding usage of multi-hypothesis prediction for intra and inter mode and separate merge list technique for subblock merge candidates even though the second control flag is transmitted only conditionally.

Abstract: The present disclosure relates to video encoding and decoding, and in particular to determining motion information for a current block using a history-based motion vector predictor, HMVP, list. The HMVP list is constructed, with said list being an ordered list of N HMVP candidates Hk, k=0, . . . , N?1, which are associated with motion information of N preceding blocks of the frame and precede the current block. Each HMVP candidate has motion information including elements of one or more motion vectors, MVs, one or more reference picture indices corresponding to the MVs, and one or more bi-prediction weight indices. One or more HMVP candidates from the HMVP list are added into a motion information candidate list for the current block; and the motion information is derived based on the motion information candidate list.

Abstract: A method for inverse quantization of a current block of a picture is provided. The method is performed by a decoder, and the picture comprises a luminance component and a chrominance component, where the luminance component and the chrominance component are partitioned into multiple blocks. The method includes obtaining one or more existing quantization parameter (QP) values from a received bitstream, wherein the one or more existing QP values are associated with a current block in the chrominance component; determining a QP value for the current block in the chrominance component based on the one or more existing QP values; performing inverse quantization on the current block in the chrominance component using the determined QP value.

Abstract: A filter is configured for processing a reconstructed frame for generation of a filtered reconstructed frame, and wherein the reconstructed frame comprises a plurality of pixels. The filter includes one or more processor configured to scan a current pixel of the reconstructed block and its neighboring pixels of the current pixel according to a predefined scan template, obtain spectrum components by performing transform for the current pixel and its neighboring pixels, obtain filtered spectrum components based on a filtering parameter and the spectrum components, obtain filtered pixels by performing inverse transform for the filtered spectrum components, and generate a filtered reconstructed block based on the filtered pixels.

Abstract: The present invention relates to an improved apparatus and method for harmonizing both Sign Bit Hiding (SBH) and Residual Sign Prediction (RSP) techniques in video coding. In order to improve coding efficiency, a list of transform coefficients, to which RSP is to be applied is prepared in advance of selecting a coefficient to which SBH is applied. Thereby, the RSP list can be populated in such a manner that the highest coding efficiency may be expected. Subsequently, one or more coefficients for applying SBH are selected so as not to be included in the list.

Abstract: The present disclosure provides embodiments for coding and decoding signs of transformation coefficients which is applicable, for instance, in image and/or video coding and decoding. In particular, a plurality of the signs are predicted and only a prediction error signal is embedded in the bitstream. The prediction error signal may have a distribution which can be efficiently coded with CABAC or another variable length (entropy) coding. In order to perform the prediction of the signs efficiently, the signs of a plurality of coefficients of a transformed image block are predicted based on a cost function including transformed difference between adjacent pixels neighboring the transformed image block and prediction of the adjacent pixels calculated based on a prediction signal of the image block.

Abstract: An apparatus and a method for image coding with asymmetric partitioning are disclosed. Instead of a conventional approach of using partitioning mechanisms such as QTBT and Multi-Type Tree (MTT), an asymmetric partitioning mechanism that can provide a good performance/complexity tradeoff is introduced. This allows constraining parameters of the asymmetric partitioning mechanism to exclude modes that appear not frequently, thereby allowing keeping encoder-side complexity low and avoiding signaling overhead.