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Three-dimensional subband video transmission through mobile satellite channels

Pyramidal vector quantization (PVQ), with its robust fixed-rate property, has been applied to two-dimensional (2-D) image coding. We extend the PVQ scheme to three-dimensional (3-D) subband video coding and apply it to shadowed mobile satellite channels. The Canadian geostationary mobile satellite channel has been modeled as shadowed Rician fading. The proposed scheme has efficient image compression while exhibiting graceful performance degradation in fading and shadowing as encountered in the mobile satellite channel. This ensures consistent visual quality for video signals transmitted over a shadowed fading channel with minimum delay and system complexity. Compared to the 2-D subband PVQ algorithm, the 3-D scheme can achieve 1.0-2.0 dB PSNR improvement or, equivalently, 21-34% bit rate reduction.