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We cascade an existing image coder
with carefully chosen error control coding,
and thus produce a progressive image compression scheme whose
performance on a noisy channel is significantly better than that of
previously known techniques.
The main idea is to trade off the available transmission rate between
source coding and channel coding in an efficient manner.
This coding system is easy to implement and has acceptably low complexity.
Furthermore, effectively no degradation due to channel noise can be detected;
instead, the penalty paid due to channel noise is a reduction in
source coding resolution.
Detailed numerical comparisons are given that can serve as benchmarks for
comparisons with future encoding schemes.
For example, for the 512x512 Lena image,
at a transmission rate of 1.0 bit per pixel, and
for binary symmetric channels with bit error probabilities
0.001, 0.01, and 0.1, the proposed
system outperforms other existing systems by at least
2.6 dB, 2.8 dB, and 8.9 dB,
respectively.
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