Adaptive enhancement layer motion compensation for video spatial scalability

This paper presents an adaptive motion compensation technique for encoding the enhancement layers in spatially scalable video coding. Based on the base layer reconstructed quantized prediction error, quantization parameters and motion vectors of both the base and enhancement layers, the proposed approach automatically selects either the inter-layer subband motion compensation, or encoding the enhancement layer without using any information from the base layer, which we call independent encoding. Compared to the SVC spatial scalability, the proposed adaptive method achieves an improvement up to about 0.6 dB with about 33% encoder computational complexity reduction.

1. INTRODUCTION

As video sources are desired to be represented by different spatial resolutions because of various channel conditions and customer device capabilities, spatially scalable video coding plays an important role in many video applications. To achieve spatial scalability, the video source lower resolution version is usually encoded independently as the base layer, and the refinement data are added as enhancement layers to provide higher resolution versions. Since the inputs of these spatial layers are highly correlated, inter-layer prediction mechanism should be applied to improve compression efficiency.