O. Stankiewicz, K. Wegner, “3D-CE7.a Cross check of Improved Nonlinear Depth Representation performed by Poznan University of Technology”, Joint Collaborative Team on 3D Video Coding Extension Development of ITU-T SG 16 WP 3 and ISO/IEC JTC 1/SC 29/WG 11, 3rd Meeting, JCT3V-C0166, Geneva, Switzerland, 17-23 January 2013,