A parametric non-linear algorithm for contrast based auto-focus

Automatic estimation of the lens position that provides the sharpest image given a subject scene is known as auto-focus. In this paper a new passive contrast based auto-focus algorithm for digital still and video cameras is proposed. The solution originates in the parametrization of NIP (Non-linear Image Processing) models . The closing property of these models allows superior performance especially for bright areas if compared with state of the art methods.

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