Picture quality improvement using a nonlinear filter in resolution conversion for HDTV

The resolution conversion (up-scaling) technique is important in HDTV displays, because there are still many standard definition television (SDTV) contents. A number of approaches which presumes high frequency components by nonlinear processing have been studied. The problem of these methods is that they augment the noise in the flat areas of the picture. In this paper, we propose a new resolution conversion method using the median filter. We obtain good quality pictures with high resolution and low noise in flat areas compared with the conventional method. The filtering computation is very small, so that it is easy to use in HDTV receivers.