A video decoding method performed by a video decoding apparatus , comprising steps of: obtaining (S1600) high frequency, HF, filtering information through a bitstream; deriving (S1610) a frequency domain reconstructed block by performing frequency transform on a reconstructed block of a current block in a spatial domain; deriving (S1620) a low frequency, LF, component of the frequency domain reconstructed block based on low pass filtering for the frequency domain reconstructed block; deriving (S1630) a high frequency component of the frequency domain reconstructed block based on the frequency domain reconstructed block and the low frequency component of the frequency domain reconstructed block; filtering (S1640) the high frequency component based on the HF filtering information; deriving (S1650) a modified frequency domain reconstructed block based on the filtered high frequency component and the low frequency component; and deriving (S1660) a modified reconstructed block of the spatial domain for the current block based on frequency inverse transform for the modified frequency domain reconstructed block, wherein if a size of the frequency domain reconstructed block is NxN, coordinates of a top-left frequency component of the frequency domain reconstructed block are , and a threshold of the low frequency component is n, transform coefficients belonging to transform coefficients within the frequency domain reconstructed block and included in a region within an n-th column in an x axis and within an n-th row in a y axis are included in the low frequency component, and wherein the frequency transform is a block based discrete cosine transform, DCT. obtaining (S1600) high frequency, HF, filtering information through a bitstream; deriving (S1610) a frequency domain reconstructed block by performing frequency transform on a reconstructed block of a current block in a spatial domain; deriving (S1620) a low frequency, LF, component of the frequency domain reconstructed block based on low pass filtering for the frequency domain reconstructed block; deriving (S1630) a high frequency component of the frequency domain reconstructed block based on the frequency domain reconstructed block and the low frequency component of the frequency domain reconstructed block; filtering (S1640) the high frequency component based on the HF filtering information; deriving (S1650) a modified frequency domain reconstructed block based on the filtered high frequency component and the low frequency component; and deriving (S1660) a modified reconstructed block of the spatial domain for the current block based on frequency inverse transform for the modified frequency domain reconstructed block, wherein if a size of the frequency domain reconstructed block is NxN, coordinates of a top-left frequency component of the frequency domain reconstructed block are , and a threshold of the low frequency component is n, transform coefficients belonging to transform coefficients within the frequency domain reconstructed block and included in a region within an n-th column in an x axis and within an n-th row in a y axis are included in the low frequency component, and wherein the frequency transform is a block based discrete cosine transform, DCT. <EOS>