ARA tools
Augmented Reality Audio tools
Augmented Reality Audio is used in many mobile applications like geolocalized games, non- linear audio walking tours, navigation systems for visually impaired people. Different types of navigation will require different types of applications. For example, a mountain biker navigation application will be very different from a guidance application for visually impaired people.
The rendering of an ARA scene can be experimented through the use of bone conduction headsets, headphones with integrated microphones or earphones with acoustically transparent earpieces, with the audio being played by a mobile phone. ARA applications can be designed so that they do not interfere with the user practicing other activies, i.e., the application leaves the user’s hands free and does not require visual attention from the user.
All of the three characteristics of an AR system set different requirements for ARA software and hardware.
- an ARA scene has to be authored through the join use of two XML languages, one for the representation of the real world and the other one for the representation of the 3D virtual audio scene, the link between the two being done through a tag- based dispatching language.
- for interaction in mobile usage, outdoor tracking has to be done through GPS and indoor tracking through embedded sensors like accelerometers and magnetometers or external ranging sensors. A user of an ARA application can interact via the microphones in the headset, speech or sound recognition being be used for controlling the application. The audio language must be an event-based language to allow interactive audio through instantiation of sound models.
- for 3D rendering of sound objects, the user’s position and orientation need to be estimated in real time. With real-time head tracking the virtual sound objects can be tied to the surrounding environment and thus the virtual environment stays in place even if the user moves. Another benefit with real-time head tracking is that the dynamic cues from head rotation help localizing sound objects in the environment, especially for front-back confusion.
A2ML iOS engine for Interactive Audio
This engine implements the version of A2ML which is describe by the following schema.
iA2ML
This engine implements a light interactive version of A2ML which is describe by a RELAX NG schema.
Software Distribution
Our ARA tools can be downloaded from the INRIA Forge .