Sound Mapper


This project, built in Pure Data, is an attempt to map location through means other than the usual pinpointing on a map. Observers are able to deduct an approximate location of participants within the space depending on the audio that is played. I created a patch that employs participants as active contributors through movement. As the participants move left to right across a space, specific sounds are triggered, increasing or decreasing in frequency. The role of the participant is also reflected visually through live video footage shot through the webcam. This video footage pans in all directions, following the participant and ensuring that they are the focus of the frame.

This patch uses ReacTIVision for Pure Data to track the position of fiducial markers within the video frame. ReacTIVision translates the x-position and y-position of the fiducials into numerical values that can be manipulated to suite the needs of the patch. To import the ReacTIVision data, a Tuio Client object box was created which routes five numerical values into separate number boxes. These number boxes provide information concerning the fiducial ID, in this case either number 1,2 or 3, the x-position and y-position of the fiducial markers and the angle of rotation. The route object is also used to tell the Pure Data console when a fiducial marker is added and removed from the screen.

The fiducial ID number box outputs its data to a gate, which sends the information through the corresponding output and unpacks it into number boxes. This allows each fiducial to be treated separately, and be given individual audio qualities.

Each fiducial marker has different audio qualities, ensuring that the participants are able to differentiate themselves from one another. This patch uses a maximum of three fiducial markers at any one time to avoid overwhelming the soundscape. The audio for Fiducial One is created with an oscillator and a delay so that the tone stops playing after 1150 milliseconds. This cosine wave generates audio similar to the sound of a bell. The second fiducial triggers audio that grows louder over 500 milliseconds before fading away. This sound is created with multiple oscillators. The audio for the third fiducial marker combines sounds from an oscillator and a phasor. The delay stops playing the sound after 1200 milliseconds. Combined, the sawtooth wave generated by the phasor object and cosine wave of the oscillator create a tone with a buzzing quality.


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