Method for reducing arbitrary-ratio up-sampling operation using context of macroblock, and method and apparatus for encoding/decoding by using the same

The present invention relates to a zoom method of a video signal, and more particularly, to a method effective image enlarged by the information of the neighboring blocks and the scalable video encoding / decoding apparatus and method for applying them. Any method of expanding a low-resolution image corresponding to the high resolution image in accordance with the present invention comprises the steps in which the low-resolution image data, determining whether the inter mode; And in the case where the low-resolution image data of an inter mode, and a step for performing image enlargement adaptively according to the macroblock mode of the low-resolution image. Scalable, Up-sampling, the macro-block