A contour preserving FPGA architecture for PAL to XGA format conversion

Frame format conversion represents a key part of video display systems, as usually the transmission video stream resolution is different from the screen resolution of the digital display. In this paper a contour-preserving approach for video up-scaling is proposed, along with a low-cost, efficient FPGA architecture for one of the most used format conversions, namely PAL to XGA. The algorithm first checks for edges existence within the region around the pixel to be interpolated and adapts the scaling method following the contour direction. This adaptive system keeps the edges sharp and provides good quality scaled video sequences when compared with other scaling methods. Moreover, we propose an FPGA implementation for handling the algorithm reload, very efficient in terms of resources and complexity.