Provided are a video decoding method and apparatus including: in a video encoding and decoding process, determining parity information of a current block based on a width and a height of the current block; determining a lookup table of the current block from among a plurality of predefined lookup tables based on the parity information; determining a dequantization scale value of the current block based on the lookup table of the current block; and performing dequantization on the current block by using the dequantization scale value.