The new generation of coding techniques for wireless multimedia: a performance analysis and evaluation

This paper presents the performance evaluation of the Mobile Audio Visual Terminal (MAVT) audio coder, candidate to the new standard, MPEG-4. By exploiting the embedded property of the object oriented coding technique, which allows scalability of the signal bandwidth as well as of the delivered bit rate, it is possible to achieve a strong interaction between the system and the bit-stream. In this way, the run-time quality of the service may be modified without changing the encoder configuration. We estimate the speech quality degradation due to bit rate reduction, and the robustness to packet losses due to network congestion, to determine the acceptable reduction and discarding thresholds. Both narrowband and wideband speech services are evaluated.