The Design of VoIP Systems with High Perceptual Conversational Quality - Ubiquitous Multimedia Computing - page 67

1. We have presented a statistical approach based on a JND to
significantly reduce the large number of subjective tests, as well as
a classification method to automatically learn and generalize the
results to unseen conditions. Using network and conversational
conditions measured at run time, the classifier learned helps adjust
the control algorithms in achieving high perceptual conversational
q u a l it y.
2. We have described the concept of a cross-layer speech codec to inter-
face with the LC and POS algorithms in the packet-stream layer in
order to be more robust and effective against packet losses.
3. We have presented a distributed algorithm for equalizing mutual
silences and an overlay network for multi-party VoIP systems. The
approach leads to multi-party conversations with high listening-
only speech quality and balanced mutual silences.
Acknowledgment
Research supported by National Science Foundation Grant CNS 08-41336.
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