The present invention relates to block merging according to block split among video coding techniques, and a method and an apparatus for coding and decoding a video, in which in generating and modifying a block merging list, spatial merging candidate blocks of the block merging list are changed according to a split type and order of a current coding unit.

The present disclosure relates to encoding and decoding of signal and syntax elements to/from a bitstream. In the encoding/decoding, semantics for the syntax elements is derived in accordance with previously decoded signal samples. Such encoding/decoding is applicable for instance to a video or audio signal.

An image encoding device 1 of the present disclosure includes: a neighboring pixel non-reference predictor 11 for generating a predicted image by predetermined neighboring pixel non-reference prediction with respect to each pixel signal of an original image of a block unit; a filter processor 12 for performing a low-pass filter process to a prediction signal located at a boundary of a block of the predicted image by using the decoded neighboring signal neighboring to the block of the predicted image; a prediction residual signal generator 55 for generating a prediction residual signal of a block unit using an predicted image of a block unit; an orthogonal transformer 14 for dividing the prediction residual signal of the block unit into block shapes designated in advance. An image decoding device 5 of the present disclosure includes a neighboring pixel non-reference predictor 53, a filter processor 54, and an inverse orthogonal transformer 52, that are corresponding to the image encoding device 1.

An encoder that encodes a current block in a picture includes circuitry and memory. Using the memory, the circuitry: performs a first transform on a residual signal of the current block using a first transform basis to generate first transform coefficients; and performs a second transform on the first transform coefficients using a second transform basis to generate second transform coefficients and quantizes the second transform coefficients, when the first transform basis is the same as a predetermined transform basis; and quantizes the first transform coefficients without performing the second transform, when the first transform basis is different from the predetermined transform basis.

An image decoding method performed by a decoding apparatus according to the present disclosure includes receiving a bitstream including residual information; deriving quantized transform coefficients for a current block based on the residual information included in the bitstream; deriving residual samples for the current block based on the quantized transform coefficients; and generating a reconstructed picture based on the residual samples for the current block.

A super-resolution coding mode is described. Encoded image can be decoded by decoding, from an encoded bitstream, a flag indicating whether an image was encoded using the super-resolution mode. The image is encoded at a first resolution. Responsive to the flag indicating that the image was encoded using the super-resolution mode, bits indicating an amount of scaling of the image are decoded. The image is decoded from the encoded bitstream to obtain a reconstructed image at the first resolution, and the reconstructed image is upscaled to a second resolution using the amount of scaling to obtain an upscaled reconstructed image. The second resolution is higher than the first resolution. Loop restoration filtering is applied to the upscaled reconstructed image using loop restoration parameters to obtain a loop restored image at the second resolution.

A method for video decoding in a decoder includes deriving for a block encoded under an intra prediction mode, a candidate list that includes a first candidate intra prediction mode value (Mode.sub.1) that corresponds to an intra prediction mode of a neighbor block that neighbors the encoded block as a first one of the plurality of intra prediction modes, and a second candidate intra prediction mode value (Mode.sub.2) and a third candidate intra prediction mode value (Mode.sub.3) that are determined in accordance with a predetermined offset from the first candidate intra prediction mode value and a modulo M operation, in which M is a power of 2 and not equal to 32. The method further includes determining an intra prediction mode value for the encoded block in accordance with the derived candidate list.

A method for encoding a digital image divided into a plurality of blocks of pixels. The method includes, for a current block: processing the current block to provide a set of description elements; selecting a subset of description elements to be predicted; ordering the description elements of the subset into an ordered sequence; and encoding the elements of the sequence. Encoding includes scrolling the elements of the sequence and includes, for a current element: selecting a combination of predicted values of the description elements of the current sequence from a plurality of possible combinations based on a predetermined cost criterion and from the second element, values of description elements previously processed of the initial sequence; predicting the current element of the sequence by its value in the selected combination; and encoding an indicator representative of a difference between the actual value of the current element and its predicted value.

An image encoding device is disclosed that performs an operation of generating a predicted image of a target block. The prediction operation is a type of operation that does not use neighboring pixels. The image encoding device further performs operations of performing a low-pass filter process on a prediction signal located at a boundary of the predicted image of the target block, using a decoded neighboring signal, generating a prediction residual signal of target block using the predicted image of the target block, and dividing the prediction residual signal of the target block unit block shapes designated in advance.

Sign prediction technology for video coding are generally described. An example device includes a memory configured to store video data, and processing circuitry in communication with the memory. The processing circuitry is configured to determine that a block of the video data stored to the memory is eligible to be coded using sign prediction, to perform the sign prediction with respect to one or more transform coefficients of the block only if the block meets a predetermined criterion, wherein the predetermined criterion is based on at least one of: a width of the block, a height of the block, a coding mode used to code the block, or a position of one or more sign-predicted transform coefficients within the block, and to code the block based on the sign prediction performed with respect to the block.