M. Papas, T. Houit, D Nowrouzezahrai, M. Gross, W. Jarosz
Proceedings of ACM SIGGRAPH Asia (Singapore, November 28 - December 1, 2012), ACM Transactions on Graphics, vol. 31, no. 6, pp. 186:1-186:10
Abstract
Motivated by classical steganography techniques we construct Magic Lenses, composed of refractive
lenslet arrays, to reveal hidden images when placed over potentially unstructured printed or
displayed source images. We determine the refractive geometry of these surfaces by formulating and
efficiently solving an inverse light transport problem, taking into account additional constraints
imposed by the physical manufacturing processes. We fabricate several variants on the basic magic
lens idea including using a single source image to encode several hidden images which are only
revealed when the lens is placed at prescribed rotational orientations or viewed from different
angles. We also present an important special case, the universal lens, that forms an injection
mapping from the lens surface to the source image grid, allowing it to be used with arbitrary source
images. We use this type of lens to generate hidden animation sequences. We validate our simulation
results with many real-world manufactured magic lenses, and experiment with two separate manufacturing
processes.
1Disney Research Zürich2ETH Zürich3University of Montreal
In ACM Transactions on Graphics (Proceedings of ACM SIGGRAPH Asia 2012)
We automatically design and manufacture magic lenses to warp source images into meaningful target images. Here we photograph
a source image (far left) viewed through a manufactured lens with 32×32 facets (left), resulting in four images depending on the lens’
rotational orientation atop the source.
