Presented at the 1997
IEEE International Conference on Image Processing
Digital Image Halftoning As 2-D Delta-Sigma Modulation
Thomas D. Kite (1),
Brian L. Evans (1),
Terry Sculley (2)
(1) Department of Electrical and Computer Engineering,
Engineering Science Building,
The University of Texas at Austin,
Austin, TX 78712-1084 USA
(2) ESS Technology, Inc., Austin, TX 78746 USA
for Matlab -
at UT Austin
The error diffusion algorithm for digital halftoning is equivalent in
form to a noise-shaping feedback coder, a class of delta-sigma modulator.
The white noise assumption of the quantizer error is known to be false;
in fact, the quantizer error is seen to be highly correlated with the input
image. To account for this correlation, we use a gain model for
This model accurately predicts the edge sharpening and noise shaping
caused by all error diffusion schemes.
It also permits an extension of error diffusion to oversampled imagery.
Last Updated 11/07/04.