A Hidden-picture Puzzles Generator

Jong-Chul Yoon, In-Kwon Lee and Henry Kang

Dept. of Computer Science, Yonsei University
Dept.of Mathematics and Computer Science, University of Missouri, St. Louis

Abstract.

A hidden-picture puzzle contains objects hidden in a background image, in such a way that each object fits closely into a local region of the background. Our system converts image of the background and objects into line drawing, and then finds places in which to hide transformed versions of the objects using rotation-invariant shape context matching. During the hiding process, each object is subjected to a slight deformation to enhance its similarity to the background. The results were assessed by a panel of puzzle-solvers.

Paper: A Hidden-picture Puzzle Generator, J.-C Yoon, I.-K Lee and Henry Kang, to appear in Pacific graphics 2008. <pdf>

Experimental Results.
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Comparision with manually created result .

We made an experiment on the real hand-drawn hidden picture puzzle. After eliminating the hidden objects from the hand-drawn version of the puzzle, we apply our method to find the places to hide the same hidden objects. Some objects are hidden at the same spots in the image, but some are not. But, anyway, the objects seem to be hidden at appropriate places.

 


(a) list of hidden object.

(b) manually generated hidden-picture puzzle by Maurie Jo Manning. (link)

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(c) manually eliminated the hidden object of (a).

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(d) hidden-picture puzzle generation with our system using the (c) and hidden object.

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