Stereo image sequence coding based on three-dimensional motion estimation and compensation

Abstract

A method that performs 3-D motion estimation for stereoscopic image sequences is presented. The 2-D motion of each object observed in one of the two views is modelled using a 3-D motion model involving a translation and a rotation. The estimation of model parameters is performed in two steps: a linear step involving 2-D vectors that are initially estimated using block matching techniques followed by a non-linear step involving displaced frame difference minimization. The regions where the 3-D model is applied are identified using a motion-based split and merge technique. Furthermore, an extension of the 3-D motion estimation method that uses a single 3-D motion model to describe the apparent 2-D motion in both channels is examined. These 3-D motion estimation methods are then integrated in a stereoscopic interframe coding scheme. A hybrid coder using block-based coding as a fall-back mode in cases where 3-D motion estimation fails, is proposed. Experimental results demonstrate the performance of the proposed coding scheme.