Generic method for 2D image resizing with simple, non-separable filters

Low-resolution pictures look bad on high-resolution screens, especially when only simple up-conversion methods like pixel and line repetition or bilinear interpolation are used. Even when applying separable polyphase up-conversion filters, the problem of jagged lines (staircases) remains. The approach investigated for high-quality resizing by rational factors is based on pixel and line repetition with suitable post-filtering. The novel resizing method uses very simple, non-separable filters, and is suitable for all kinds of image and video material such as analog sources (PAL, NTSC) digital sources (JPEG, MPEG), low-resolution up to high-resolution images or photos, and noisy pictures. Jagged lines can be smoothed perfectly.