Reduced complexity inverse discrete cosine transform (IDCT) masks and a method for reducing the number of IDCT calculations in video decoding are provided. The method comprises: accepting an n.times.m matrix of DCT coefficients; performing (n-y) horizontal IDCT operations, where y is greater than 0; performing y scaling operations; and, generating an n.times.m block of pixel information. Some aspects of the method further comprise: performing (m-z) vertical IDCT operations, where z is in the range between 0 and m/2. In some aspects, performing (n-y) horizontal ICDT operations includes performing IDCT operations for the first (n-y) horizontal rows. Then, performing y scaling operations includes: selecting the DC component from the first position of each horizontal row; scaling the selected DC component; and, copying the scaled DC component into the remaining positions of each of horizontal row.

 
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