Apparatus for converting resolution of image applied to transcoder and method of the same

The resolution conversion apparatus and method applied to a transcoder is disclosed. Cubic convolution interpolation unit comprises: a second size continuous video data having a second resolution by the discrete image data decoded in the first size having a first resolution in a cubic convolution interpolation function modified to create a longitudinal slope to a fixed value It is converted to. A sampling unit to sample material by the continuous video data to a predetermined scaling factor. According to the invention, it is possible to increase the quality of the reconstructed image, can reduce the loss of information occurring in the size conversion process, it is possible to reliably resolution conversion by any scaling factor. Resolution conversion, cubic convolution interpolation, the transcoder, MPEG