Compression Issues in Multiview Autostereo Displays

Image compression for multi-view autostereoscopic displays is one of the major governing factors for the development and acceptance of 3D technology. For example: the multi-view autostereo display developed at Cambridge uses between six and twenty-eight distinct views of the scene, each view being a complete image of the scene taken from a particular view point. Therefore it is of prime importance to use compression methods that would exploit the redundancy present in the view-point direction to allow for 3D image communication since the images require a very high bandwidth for transmission and a large amount of space for storage. In this paper an initial investigation on how the third dimension can be utilised is presented. Entropy measures for multi-view images are derived. It is shown that exploiting the similarities between views can give lower entropy, indicating higher compression rates. The parallel axes geometry of the cameras used for the autostereo display produces only horizontal shifts between stereo images, therefore investigation in using hierarchical row decomposition along with correlation and mean squared error measures for estimating disparity shifts and reducing search spaces respectively are presented.