A fully digital auto-focusing system based on point-spread function (PSF) estimation is proposed. To increase accuracy in estimating the PSF of the defocused image, the input image is subdivided, and the step responses of edge-containing subimages are averaged. The PSF, which results from out-of-focus blur, is estimated by differentiating the averaged step response along the appropriately estimated edge direction under the assumption that an image usually contains a piece-wise linear boundary between an object and background. By using the estimated PSF, the corresponding image restoration filter is realised, based on the constrained least squares approach.


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    Title :

    Out-of-focus blur estimation and restoration for digital auto-focusing system


    Contributors:
    Kim (author) / Paik (author)

    Publication date :

    1998-06-11


    Size :

    3 pages



    Type of media :

    Article (Journal)


    Type of material :

    Print


    Language :

    English




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