A video and graphics system includes a video decoding system for
processing compressed video data. The compressed video data includes
MPEG-2 video data containing SDTV video data or HDTV video data. The
video decoding system includes a video decoder for processing the
compressed video data to generate displayable video, and a memory
controller for transferring the compressed video data to and from an
external memory. The video decoder requests to the memory controller to
transfer the compressed video data using one of predetermined addressing
patterns. The predetermined addressing patterns allow for more efficient
transferring of the compressed video data to and from the external memory
when compared to sequentially transferring a fixed number of data bytes
starting at a fixed address. The use of the predetermined addressing
patterns results in reading the compressed video data from the external
memory in a predetermined order in a less number of clock cycles. The use
of the predetermined addressing patterns also results in transferring the
compressed video data over the data bus between the memory controller and
the video decoder in a less number of clock cycles.