TITLE:        Transform coding of images using trellis coded quantization
AUTHORS:      M. W. Marcellin
CONFERENCE:   International Conference on Acoustics, Speech, and Signal 
              Processing, Albuquerque, New Mexico, April 1990
ABSTRACT:
Trellis coded quantization (TCQ) is incorporated into a transform coding 
structure for encoding monochrome images.  Both fixed-rate and 
entropy-constrained designs are considered. The fixed-rate TCQ-based 
systems provide gains in peak signal-to-noise ratio of up to 4.13 dB 
over scalar quantizer-based schemes, while the entropy-constrained 
TCQ-based systems provide gains of up to 6.39 dB. The subjective 
quality of the TCQ-based systems is substantially better than that of 
comparable scalar quantizer-based systems.  The high frequency background 
noise, fuzziness, and block artifacts produced by the scalar 
quantizer-based systems are virtually eliminated by the TCQ-based systems.