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Mobile wideband speech communication (HD Voice) is more and more available in the past years, primarily in 3G networks. The specifics of mobile communication - even if it is packet-switched - is that received frames with residual bit errors after channel decoding must not necessarily be marked as lost, instead they may be marked as bad (bad frame indicator,(More)
Variable-length codes (VLCs) are widely used in media transmission. Compared to fixed-length codes (FLCs), VLCs can represent the same message with a lower bit rate, thus having a better compression performance. But inevitably, VLCs are very sensitive to transmission errors. In this work, based on the trellis representation for VLCs and the BCJR algorithm,(More)
Lloyd-Max quantization (LMQ) is a widely used scalar non-uniform quantization approach targeting for the minimum mean squared error (MMSE). Once designed, the quantizer codebook is fixed over time and does not take advantage of possible correlations in the input signals. Exploiting correlation in scalar quantization could be achieved by predictive(More)
Adaptive differential pulse code modulation (ADPCM) has been standardized in ITU-T Recommendations G.726 and G.722 and is widely used in IP and cordless telephony. Although adaptive quantization and adaptive prediction is employed in ADPCM using a fixed scalar quantization codebook/lookup table, residual correlation of the quantizer input samples is yet(More)
The ITU-T Recommendation G.722 about subband adaptive differential pulse code modulation (SB-ADPCM) is the mandatory wideband speech codec in the new generation digital enhanced cordless telephony (NG-DECT). Although in ADPCM the difference signal instead of the original signal is quantized and adaptive prediction is employed, redundancy is yet observed(More)
Islet transplantation is a therapeutic option for type 1 diabetes, but its long-term success is limited by islet allograft survival. Many factors imperil islet survival, especially the adverse effects and toxicity due to clinical immunosuppressants. Compound (Cpd) K is a synthesized analog of highly unsaturated fatty acids from Isatis tinctoria L.(More)
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