Using disparity map for directional adaptive lifting scheme for stereo image residuals

The advances in 3D technologies and applications is leading to more research effort for developing and improving stereo image compression techniques. In this paper, we propose a specialized transform for stereo image residuals. The particularities of the residual image are considered and consequently an adaptive Lifting Scheme is used. The novelty of this work is the use of the edge or orientation information in the disparity map to adapt the proposed scheme. An edge/orientation map is generated from the disparity map, and for each pixel, the direction or the length of filtering are tuned by the edge/orientation map. The proposed schemes does not require any extra overhead information. Comparison between the Directional and the Hybrid Lifting Scheme is made compared to traditional 5/3 transform. Experimental results show an improvement of 0.13 bpp compared to the traditional 5/3 transform and 0.18 bpp to Haar transform.