Method and apparatus for encoding and decoding images by adaptively using an interpolation filter

A method for encoding an image, comprising:

• adaptively selecting an interpolation filter from a filter bank that stores a plurality of interpolation filters arranged in groups according to context information by taking into account the context information, the context information including at least one of coding mode information, a quantization value, pixel position information indicating whether a pixel to be encoded is located in an area at a boundary between two image blocks, and a pixel resolution of an image block;
• interpolating a reference image block related to an input image block using the selected interpolation filter;
• and
• determining, as an interpolation filter for generating a prediction block for the input image block, an interpolation filter that minimizes an error difference between the input image block and the reference image block.