Quadtree-based disparity estimation for intermediate view synthesis of stereoscopic image sequences

In stereoscopic or multiview 3-D display systems, the synthesis of intermediate sequences is essential to assure lookaround capability and continuous motion parallax so that it can enhance comfortable 3-D perception. The quadtree-based disparity estimation is one of the most popular methods for the synthesis of intermediate sequences, due to the simplicity of its algorithm and hardware implementation. We propose two solutions in order to reduce annoying flicker at object boundaries of synthesized intermediate sequences using quadtree-based disparity estimation. The first requires a new splitting scheme, providing more consistent quadtree splitting strategies during the disparity estimation. The second involves adaptive temporal smoothing, using the dissimilarity between the present frame and the previous one to reduce the error of disparity estimation. These two proposals are tested by using several stereoscopic sequences, and the results show that flicker is remarkably reduced by them.