Design of an efficient Receiver based Packet Loss Concealment technique for Voice over Internet Protocol Using Speech Property-Based Marking Scheme

Packet loss is a common challenge to provide efficient Quality of Service support in VoIP. Present VoIP architecture does not guaran- tee a minimum amount of packet loss and a mini- mum delay of packet transmission required for voice communication. The recent work has shown that in voice transmission of all the packets are not of same importance or priority. Some seg- ments of the signal are essential to the speech quality while others are not so much essential and this gives the concept of prioritizing the informa- tive packets of the voiced stream which provides good voice quality and also ensures the efficient use of the network resources. To provide efficient QoS support selective packet marking procedure is better than using "best effort" principle. We have proposed to use SPB-MARK scheme for prioritization of voiced packets. Again using packet loss concealment algorithm (PLC), the quality of service for voice over IP can be im- proved but the PLC techniques described in the standards ANSI TI.521 and ITU-T Rec. G.711 fail to reconstruct the lost packet if it is the first packet in the voiced stream as no previous pack- ets are available for reconstruction of that packet. For this, we propose a special buffer to store the information of first three voiced packets for the reconstruction of the lost packets. Tests on recon- structed packets those are lost have proved that the proposed method improves the reconstructed speech quality significantly.