Arto Lehtonen

Nonlinear quincunx interpolation filtering

Quincunx sub-sampling and interpolation techniques are widely used in many image and video signal bandwidth compression techniques like HDTV transmission systems. In this paper we consider the basic quincunx interpolation problem: interpolation of the missing samples of an orthogonally sampled image after quincunx sub-sampling with a factor of two. New median-based nonlinear interpolation techniques are developed and compared with traditional linear designs. It is shown that nonlinear interpolators result in considerably lower hardware complexity than good quality linear designs and in many respects even better image quality can be achieved.