Image enhancement by nonlinear extrapolation in frequency space

نویسندگان

  • Hayit Greenspan
  • Charles H. Anderson
  • Sofia Akber
چکیده

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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عنوان ژورنال:
  • IEEE transactions on image processing : a publication of the IEEE Signal Processing Society

دوره 9 6  شماره 

صفحات  -

تاریخ انتشار 2000