ELEC692 VLSI Signal Processing Architecture Lecture 9

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ELEC692 VLSI Signal Processing ArchitectureLectur
e 9

• VLSI Architecture for Discrete Cosine Transform

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Discrete Cosine Transform

• Frequency transform
• Used for pattern recognition, image processing,
  still and moving image and video processing
• N-point sequence x(n), N-point DCT and IDCT pair
  is defined as

where
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N-point DCT/IDCT

• N-point DCT and IDCT pair can be derived using a
  2N-point discrete Fourier transform (DFT) pair,
  using x(n) and its mirror image

Y(n) is symmetric with respect to midpoint at
nN-1/2. The 2N-point DFT of y(n) is given by
(for 0lt k lt 2N-1)
Substituting n2N-n