SCALING LIST PARAMETER-BASED VIDEO OR IMAGE CODING
According to the disclosure of the present document, scaling list data transmitted from an adaptation parameter set (APS) can be signaled through a hierarchical structure. In addition, by setting a limit on the scaling list data transmitted from the APS, it is possible to reduce the amount of data which has to be signaled for video/image coding, and facilitate implementation.
1 . An apparatus for decoding an image, the apparatus comprising:
a memory; and
at least one processor connected to the memory, the at least one processor configured to:
obtain image information including prediction mode information, residual information and a sequence parameter set (SPS) from a bitstream;
derive prediction samples for a current block based on the prediction mode information;
derive quantized transform coefficients for the current block based on the residual information;
derive transform coefficients based on the quantized transform coefficients;
derive residual samples based on the transform coefficients; and
generate reconstruction samples based on the prediction samples and the residual samples,
wherein the transform coefficients are derived by performing a dequantization process on the quantized transform coefficients based on scaling list data,
wherein the image information includes an adaptation parameter set (APS),
wherein the APS is identified based on APS ID information related to an identifier for the APS,
wherein the APS includes the scaling list data based on APS type information for APS parameters included in the APS,
wherein a range of values of the APS ID information is determined based on the APS type information, and
wherein scaling list enabled flag information for indicating whether a scaling list is used for a scaling process is included in the SPS.
2 . An apparatus for encoding an image, the apparatus comprising:
a memory; and
at least one processor connected to the memory, the at least one processor configured to:
derive prediction samples for a current block based on prediction mode information;
derive residual samples based on the prediction samples;
derive transform coefficients based on the residual samples;
derive quantized transform coefficients through a quantization process based on the transform coefficients; and
encode image information including residual information generated based on the quantized transform coefficients, the prediction mode information and a sequence parameter set (SPS),
wherein the image information includes an adaptation parameter set (APS),
wherein the APS is identified based on APS ID information related to an identifier of the APS,
wherein the APS includes scaling list data based on APS type information for APS parameters included in the APS,
wherein a range of values of the APS ID information is determined based on the APS type information, and
wherein scaling list enabled flag information for indicating whether a scaling list is used for a scaling process is included in the SPS.
3 . An apparatus for transmitting data for an image, the apparatus comprising:
at least one processor configured to obtain a bitstream for the image, wherein the bitstream is generated based on deriving prediction samples for a current block based on prediction mode information, deriving residual samples based on the prediction samples, deriving transform coefficients based on the residual samples, deriving quantized transform coefficients through a quantization process based on the transform coefficients, encoding image information including residual information generated based on the quantized transform coefficients, the prediction mode information and a sequence parameter set (SPS); and
a transmitter configured to transmit the data comprising the bitstream,
wherein the image information includes an adaptation parameter set (APS),
wherein the APS is identified based on APS ID information related to an identifier of the APS,
wherein the APS includes scaling list data based on APS type information for APS parameters included in the APS,
wherein a range of values of the APS ID information is determined based on the APS type information, and
wherein scaling list enabled flag information for indicating whether a scaling list is used for a scaling process is included in the SPS.