reacTIVision Interactive Design

ReacTIVation is a open source framework which allows tracking of fiducial markers in the physical world which can be used as an interface for programs. It was developed by Martin Kaltenbrunner and Ross Bencina as part of the Reactable project which is a MIDI table used in electronic music creation or DJing.

How it works

The system relies on objects call fiducial markers, which are special created, shapes which the system and easily recognise in the physical world. The unique style and precise geometry allow them to stand out from complex backgrounds making them directly recognised by the program. In connection to a MIDI table they can each be connected to a feature like filter, gain or base. For a DJ this could be a new experience and a unique way to create music using an unorthodox method.

The reacTIVation program can also be used with processing as a client. This means it can link to processing and features like fiducial marker tracking which could be used to track them around a space then used as input or variable. Tracking in processing can be difficult and sometimes unreliable but reacTIVation solves this providing a stable and compatible alternative to colour the only other simple option of tracking. ReacTIVation could be used not only to make music tables but such things as large interactive games where each piece could be tracked effectively around a space.

reacTIVation In Processing

reacTIVation uses Processing as a client and needs the Library TUIO to connect the two together. In the library an example is provided to demonstrate how TUIO works. By having both java and reactivation running you can see how the fiducial marker is in the cameras view and presented on the java output. Here I’m holding the fiducial relatively still with two hands. You can see that processing also recognises what number fiducial marker in relation to the set of 216. This is useful because they can be specified and called individually within processing.


Taking this forward with my installation piece in mind the reacTIVson library could be useful to me as a way to identify objects in the space. As previously discussed colour tracking is unreliable and face tracking requires a face so this could be a way of tracking an object without having to program the sketch to recognise my own set of objects.

Something to consider is could I work the fiducial into the design of a graphic or on an object so that there are not just a shape just slapped on, they are a part of the design itself becoming integrated into the environment itself. The issue with this could be recognition do they need to be black, at the forefront of the image and have a clear area around them??



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