Error resilient video transcoding for robust inter-network communications using GPRS

摘要

A novel fully comprehensive mobile video communications\udsystem is proposed in this paper. This system exploits\udthe useful rate management features of the video transcoders and\udcombines them with error resilience for transmissions of coded\udvideo streams over general packet radio service (GPRS) mobileaccess\udnetworks. The error-resilient video transcoding operation\udtakes place at a centralized point, referred to as a video proxy,\udwhich provides the necessary output transmission rates with the\udrequired amount of robustness. With the use of this proposed\udalgorithm, error resilience can be added to an already compressed\udvideo stream at an intermediate stage at the edge of two or more\uddifferent networks through two resilience schemes, namely the\udadaptive intra refresh (AIR) and feedback control signaling (FCS)\udmethods. Both resilience tools impose an output rate increase\udwhich can also be prevented with the proposed novel technique in\udthis paper. Thus, an error-resilient video transcoding scheme is\udpresented to give robust video outputs at near target transmission\udrates that only require the same number of GPRS timeslots as\udthe nonresilient schemes. Moreover, an ultimate robustness is\udalso accomplished with the combination of the two resilience\udalgorithms at the video proxy. Extensive computer simulations\uddemonstrate the effectiveness of the proposed system.