A decoder includes an entropy decoder configured to derive a number of bins of the binarizations from the data stream using binary entropy decoding by selecting a context among different contexts and updating probability states associated with the different contexts, dependent on previously decoded portions of the data stream; a desymbolizer configured to debinarize the binarizations of the syntax elements to obtain integer values of the syntax elements; a reconstructor configured to reconstruct the video based on the integer values of the syntax elements using a quantization parameter, wherein the entropy decoder is configured to distinguish between 126 probability states and to initialize the probability states associated with the different contexts according to a linear equation of the quantization parameter, wherein the entropy decoder is configured to, for each of the different contexts, derive a slope and an offset of the linear equation from first and second four bit parts of a respective 8 bit initialization value.

A decoder includes an entropy decoder configured to derive a number of bins of the binarizations from the data stream using binary entropy decoding by selecting a context among different contexts and updating probability states associated with the different contexts, dependent on previously decoded portions of the data stream; a desymbolizer configured to debinarize the binarizations of the syntax elements to obtain integer values of the syntax elements; a reconstructor configured to reconstruct the video based on the integer values of the syntax elements using a quantization parameter, wherein the entropy decoder is configured to distinguish between 126 probability states and to initialize the probability states associated with the different contexts according to a linear equation of the quantization parameter, wherein the entropy decoder is configured to, for each of the different contexts, derive a slope and an offset of the linear equation from first and second four bit parts of a respective 8 bit initialization value.

Decoding and/or encoding video information included in a bitstream can involve a predicted quantization matrix associated with at least a portion of the video information and a syntax element indicating that at least one coefficient of the predicted quantization matrix is to be interpreted as a residual such that the decoding and/or encoding of at least a portion of the video information is based on a combination of the predicted quantization matrix and the residual, where the syntax element is obtained from the bitstream during decoding, or included in the bitstream during encoding.

Decoding and/or encoding video information included in a bitstream can involve a predicted quantization matrix associated with at least a portion of the video information and a syntax element indicating that at least one coefficient of the predicted quantization matrix is to be interpreted as a residual such that the decoding and/or encoding of at least a portion of the video information is based on a combination of the predicted quantization matrix and the residual, where the syntax element is obtained from the bitstream during decoding, or included in the bitstream during encoding.

A decoding method performed by a decoding device, according to the present document, may comprise the steps of: acquiring a sequence parameter set from a bitstream; acquiring a combined inter-picture merge and intra-picture prediction (CIIP) enable flag from the sequence parameter set; determining, on the basis of the CIIP enable flag and the size of a current block, whether a regular merge flag is included in the bitstream; parsing the regular merge flag in the bitstream on the basis that a condition based on the CIIP enable flag and a condition based on the size of the current block are satisfied; generating prediction samples of the current block on the basis of the regular merge flag; and generating a restoration picture on the basis of the prediction samples.

A decoding method performed by a decoding device, according to the present document, may comprise the steps of: acquiring a sequence parameter set from a bitstream; acquiring a combined inter-picture merge and intra-picture prediction (CIIP) enable flag from the sequence parameter set; determining, on the basis of the CIIP enable flag and the size of a current block, whether a regular merge flag is included in the bitstream; parsing the regular merge flag in the bitstream on the basis that a condition based on the CIIP enable flag and a condition based on the size of the current block are satisfied; generating prediction samples of the current block on the basis of the regular merge flag; and generating a restoration picture on the basis of the prediction samples.

Methods are provided for inter-prediction candidate index coding independent of the construction of the corresponding inter-prediction candidate list, i.e., a merging candidate list or an advanced motion vector predictor list. A maximum allowed number of inter-prediction candidates for an inter-prediction candidate list is used for encoding the inter-prediction candidate index in an encoded bit stream. The maximum allowed number may be pre-determined or may be selected by the encoder and encoded in the bit stream. A decoder may then decode the index using the maximum allowed number of inter-prediction candidates independent of the construction of the corresponding inter-prediction candidate list.

Methods are provided for inter-prediction candidate index coding independent of the construction of the corresponding inter-prediction candidate list, i.e., a merging candidate list or an advanced motion vector predictor list. A maximum allowed number of inter-prediction candidates for an inter-prediction candidate list is used for encoding the inter-prediction candidate index in an encoded bit stream. The maximum allowed number may be pre-determined or may be selected by the encoder and encoded in the bit stream. A decoder may then decode the index using the maximum allowed number of inter-prediction candidates independent of the construction of the corresponding inter-prediction candidate list.

An image decoding method and an image decoding apparatus is provided. The method comprises recovering a first motion vector corresponding to a first decoding reference picture based on the entropy decoded bit stream, calculating a second motion vector corresponding to a second decoding reference picture by scaling the first motion vector based on a first temporal distance between the current picture and the first decoding reference picture and a second temporal distance between the current picture and the second decoding reference picture, generating a prediction block relating to a current block in the current picture, based on the calculated second motion vector, generating a residual block relating to the current block through a residual data decoding process based on the entropy decoded bit stream, and recovering the current block based on the prediction block and the residual block.

An image decoding method and an image decoding apparatus is provided. The method comprises recovering a first motion vector corresponding to a first decoding reference picture based on the entropy decoded bit stream, calculating a second motion vector corresponding to a second decoding reference picture by scaling the first motion vector based on a first temporal distance between the current picture and the first decoding reference picture and a second temporal distance between the current picture and the second decoding reference picture, generating a prediction block relating to a current block in the current picture, based on the calculated second motion vector, generating a residual block relating to the current block through a residual data decoding process based on the entropy decoded bit stream, and recovering the current block based on the prediction block and the residual block.