Enhanced inter-prediction using Merge Prediction Transformation in the HEVC codec

Abstract

Merge prediction is a novel technique introduced in the HEVC standard to improve inter-prediction exploiting redundancy of themotion information. We propose in this paper a new approach to enhance the Merge mode in a typical HEVC encoder using parametric transformations of the Merge prediction candidates. An Enhanced Inter-Prediction module is implemented in HEVC using Merge Prediction Transformation (MPT), integrated with the HEVC new features such as the large coding units (CU) and the recursive prediction unit partitioning. The MPT parameters are quantised according to the CU depth and the current QP. The optimal quantization steps are derived via statistical analysis as illustrated in the paper. Results show consistent improvements over conventional HEVC encoding in terms of rate-distortion performance, with a small impact on the encoding complexity and negligible impact on the decoding complexity.