Image enhancement by nonlinear extrapolation in frequency space
H Greenspan1, C H Anderson, S Akber
1Fac. of Eng., Tel Aviv Univ., Israel. hayit@eng.tau.ac.il
Abstract:
A technique for enhancing the perceptual sharpness of an image is described. The enhancement algorithm augments the frequency content of the image using shape-invariant properties of edges across scale by using a nonlinearity that generates phase coherent higher harmonics. The procedure utilizes the Laplacian transform and the Laplacian pyramid image representation. Results are presented depicting the power-spectra augmentation and the visual enhancement of several images. Simplicity of computations and ease of implementation allow for real-time applications such as high-definition television (HDTV).
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