Fast edge-filtered image upsampling

Laboratory of Neuro Imaging, University of California, Los Angeles, CA 90095, USA.
Proceedings / ICIP ... International Conference on Image Processing 09/2011; DOI: 10.1109/ICIP.2011.6115636
Source: PubMed


We present a novel edge preserved interpolation scheme for fast upsampling of natural images. The proposed piecewise hyperbolic operator uses a slope-limiter function that conveniently lends itself to higher-order approximations and is responsible for restricting spatial oscillations arising due to the edges and sharp details in the image. As a consequence the upsampled image not only exhibits enhanced edges, and discontinuities across boundaries, but also preserves smoothly varying features in images. Experimental results show an improvement in the PSNR compared to typical cubic, and spline-based interpolation approaches.

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