Method and apparatus for performing intra-prediction using adaptive filter

A video encoding method comprising:

• encoding information related to whether to apply a first filter for a reference pixel value of a current block and whether to apply a second filter for a prediction value of the current block,
• wherein the information is related to at least one of an intra prediction mode of the current block and a size of the current block, and
• wherein when the intra prediction mode of the current block is a vertical mode, a filtered prediction value is generated by applying the second filter for leftmost pixels of the current block among prediction pixels of the current block adjacent to the reference pixel value.

A non-transitory computer-readable storage medium storing a bitstream, the bitstream comprising:

• information related to whether to apply a first filter for a reference pixel value of a current block and whether to apply a second filter for a prediction value of the current block,
• wherein the information is related to at least one of an intra prediction mode of the current block and a size of the current block, and
• wherein when the intra prediction mode of the current block is a vertical mode, a filtered prediction value is generated by applying the second filter for leftmost pixels of the current block among prediction pixels of the current block adjacent to the reference pixel value.