Restoration of error-diffused images using projection onto convex sets.
A novel inverse halftoning method is proposed to restore a continuous tone image from a given half-tone image. A set theoretic formulation is used where three sets are defined using the prior information about the problem. A new space-domain projection is introduced assuming the halftoning is performed using error diffusion, and the error diffusion filter kernel is known. The space-domain, frequency-domain, and space-scale domain projections are used alternately to obtain a feasible solution for the inverse halftoning problem which does not have a unique solution.
Unal
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Electr. and Comput. Eng. Dept., North Carolina State Univ., Raleigh, NC 27695-7914, USA.
Cetin
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