Coding of Depth-maps Using Piecewise Linear Functions

An efficient way to transmit multi-view images is to send a single texture image together with a corresponding depth-map. The depth-map specifies the distance between each pixel and the camera. With this information, arbitrary 3-D views can be generated at the decoder. In this paper, we propose a new algorithm for the coding of depth-maps that provides an efficient representation of smooth regions as well as geometric features such as object contours. Our algorithm uses a segmentation procedure based on a quadtree decomposition and models the depth-map content with piecewise linear functions. We achieved a bit-rate as low as 0.33 bit/pixel, without any entropy coding. The attractivity of the coding algorithm is that, by exploiting specific properties of depth-maps, no degradations are shown along discontinuities, which is important for depth perception.