A method of concealing an image in a different halftone image is
proposed. Continuous-tone levels of the visible images are
represented by the area of the halftone dots. However, the hidden
image is encoded by the dots’ positions inside their cells. Only a
spatial correlator with a unique filter function can reveal the hidden
image from the halftone picture. The technique and its robustness
to noise and distortions are demonstrated.
© 2001 Optical Society of America
Equations on this page are rendered with MathJax. Learn more.