Decimating MPEG or other video data by subsampling the output of an inverse
discrete cosine transform (IDCT) module. The decimation process is useful for reducing
the volume of data that must be processed to display images on a display device,
particularly when the volume of video data received at the decoder is greater than
the amount needed to take advantage of the resolution of the display device. For
example, high definition television data can be decimated for display on a standard
television display device or in a picture-in-picture window, thereby reducing the
amount of processing resources needed at the decoder and reducing the size of the
frame buffers. Subsampling the output of the IDCT module reduces the volume of
data and, for relatively static or constant pans, there is not a significant compounded
loss of image quality as successive frames are decoded.