Rate Distortion Performance of Pyramid and Subband Motion Compensation Based on Quantization Theory

Abstract

We present in this letter the rate distortion (RD) performance analysis of the inter-layer subband and pyramid motion compensation techniques for spatially scalable video coding. Theoretical performance functions are derived based on RD theory and quantization noise modeling. We assume the base layer is encoded by a non-scalable coder. The coding efficiency of the enhancement (enh.) layer, measured by the signal-to-noise ratio, is determined by the input video power spectral density, the motion estimation error distribution, and the base layer encoder rate. Numerical evaluations of the performance functions show that, compared to independent motion-compensated prediction encoding of the enh. layer, the inter-layer pyramid and subband methods are expected to be more efficient if the base layer is encoded at a sufficiently high quality or the motion estimation accuracy is relatively low in the enh. layer. Results from real video data encoding show that the presented theoretical analysis can be very useful to understand the efficiencies of these spatial scalability techniques.