H.263 picture header recovery in H.324 videophone

The scope of the H.324 videophone standard includes mobile networks which can in bad radio conditions be susceptible to higher bit error rates than most fixed networks. Different parts of the H.263 video bit-stream have unequal importance in video signal reconstruction. For example, the contents of a video picture cannot be decoded unless a so-called picture header has been correctly received or successfully recovered. In this paper we review methods for recovering corrupted H.263 picture headers. Moreover, we experimented how well two selected recovery methods operate in H.324 terminals connected to a simulated mobile network. The results showed that both tested algorithms play an important role in picture header recovery. In addition, we found that it is beneficial to set a certain parameter in the picture header differently than suggested in the H.263 recommendation.