A Divide-and-conquer Strategy in Recovering Surface Shape of Book from Shading
نویسندگان
چکیده
A divide-and-conquer strategy in shape from shading is proposed for recovering book surface on fully perspective condition. It is shown that unique shape can be recovered despite of more unknowns than shade images by dividing original implicit SFS problem into explicit ones. Using invariance of shading, a transformed shading equation and a recurrence relation is derived for depth recovery. Whole process is divided into three sequential processes : preprocessing, apparent shape recovery, and ortho-image generation. Comprehensive algorithms are implemented for each process. The reliability of proposed strategy and accuracy of recovered results are shown through simulations and real experiment. Key Word Shape from shading, Divide-and-conquer strategy, Transformed shading equation, Recurrence relation
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