03/18/2003
15-462 Graphics I
42
Improving Noise Tolerance
•Predictive
coding:
–Predict
next pixel based on prior ones
–Output
difference to actual
•Fractal
image compression
–Describe
image via recursive affine transformation
•Transform
coding
–Exploit
frequency domain
–Example:
discrete cosine transform (DCT)
–Used
in JPEG
•Transform
coding for lossy compression