  We propose a new algorithm for binary quantization based on the Belief
Propagation algorithm with decimation over factor graphs of Low Density
Generator Matrix (LDGM) codes. This algorithm, which we call Bias Propagation
(BiP), can be considered as a special case of the Survey Propagation algorithm
proposed for binary quantization by Wainwright et al. [8]. It achieves the same
near-optimal rate-distortion performance with a substantially simpler framework
and 10-100 times faster implementation. We thus challenge the widespread belief
that binary quantization based on sparse linear codes cannot be solved by
simple Belief Propagation algorithms. Finally, we give examples of suitably
irregular LDGM codes that work with the BiP algorithm and show their
performance.
