Simultaneous image restoration and distance estimation of an object from a strongly defocused photon image

Shinya Ono, Shinichi Komatsu

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    3 Citations (Scopus)


    We apply the filter bank method, which extracts from a strongly defocused image the information on the amount of defocus, i.e., the information on the object distance, and simultaneously restores the object, to a defocused image of extremely low intensity, which is detectable only with a photon counting camera. Experimental results show that the information of the defocus amount can be extracted from such a blurred photon image, and the original object itself is simultaneously restored. The influence of the photon noise on the distance estimation is also quantitatively investigated. Then, the maximum likelihood-expectation maximization (ML-EM) method is adopted for image restoration, and the results are compared with those obtained by applying the conventional Wiener filter, It is experimentally shown that the ML-EM produces better image restoration than the Wiener filter in the extremely low intensity region where the maximal number of photons per pixel does not exceed about 450.

    Original languageEnglish
    Pages (from-to)1024-1028
    Number of pages5
    JournalOptical Engineering
    Issue number4
    Publication statusPublished - 2003 Apr



    • Image restoration
    • Photon-limited imaging
    • Range finding
    • Semi-blind deconvolution

    ASJC Scopus subject areas

    • Atomic and Molecular Physics, and Optics

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