Robust decoding of VLC encoded Markov sources
نویسندگان
چکیده
The problem of robust decoding of VLC encoded streams in presence of channel errors is essentially a problem of joint estimation and segmentation of the bit stream. A correct segmentation and estimation of a VLC compressed stream in presence of channel noise requires to re-augment the redundancy of the stream. Instead of using a channel code, the approach described here dedicates specifically extra bits to help the VLC decoder re-synchronization. The procedure amounts to extending symbols at known positions with a suffix. These suffixes can have an arbitrary length (depending on the degree of redundancy desired) and need not be recognized with probability close to 1. They serve as anchors to favor the likelihood of correctly synchronized sequences and penalize the others.
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