soft electronics, embedded in fabric
“The marks often were created by a wire sewn onto the paper mold.” and invisible to naked eye
Ref to Steganography
01/17/2018 > hidden life of objects in the Ubiquitous Computing ! Network -Hide
Signal Rich Art:Enabling the vision of Ubiquitous Computing
” Sculpture and Other Objects
Objects with flat surfaces can obviously be watermarked in the same way that digital photography and art is watermarked, using either the historic approach or the newer ideas introduced above. Medical packaging, for example, is beginning to be watermarked during printing as a way of providing additional important resources to purchasers. Objects, however, literally offer additional dimensions to consider in watermarking. One additional dimension is that of texture. Signal can be embedded in an object by adding textured patterns or by modifying an object’s natural texture.
This form of watermarking is currently employed to track sensitive or high-value machine parts and to identify containers carrying toxic or hazardous materials. Three-dimensional objects also raise the possibility of encoding signal by arranging artistic elements in space. This possibility raises the same kinds of issues as those brought up by embedding signals in music or painting by careful arrangement of artistic elements. While practical applications do not yet exist, research has been done in watermarking 3D models through modulation of triangle vertices. 13 It can be extrapolated that such modulations would persist through the manufacturing process.”