Using the built-in camera of a mobile phone and inexpensive printed tags, users can leave and retrieve video messages in specific locations or associated to specific objects. At the heart of the project is d-touch: an open-source system for computer vision recognition of markers. D-touch's peculiarity, compared to other marker systems, is that its recognition mechanism is based on topology rather than geometry. As a consequence, the system allows considerable freedom in the visual design of the markers, so that they can be "hidden" or designed to fit the specific aesthetic requirements of different applications.
Using the built-in camera of a mobile phone and inexpensive printed tags, users can leave and retrieve video messages in specific locations or associated to specific objects. At the heart of the project is d-touch: an open-source system for computer vision recognition of markers. D-touch's peculiarity, compared to other marker systems, is that its recognition mechanism is based on topology rather than geometry. As a consequence, the system allows considerable freedom in the visual design of the markers, so that they can be "hidden" or designed to fit the specific aesthetic requirements of different applications.