Assignment 2 — Jonathan Cavell

Video Synth

Below is a patch which utilizes color information from a video to generate synth sounds through a set of delay channels.

The patch starts by sending the RGB matrix from a video source to a series of jit.findbounds objects, which locate color values within each plane of the matrix (this includes the alpha plane, but it is not utilized here since I am interested in capturing red, green, and blue color values specifically).

There are a series of poly synthesizers — one for each set of bounds the jit.findbounds objects send, with a channel for the x value and one channel for the y value. The number values are “seen” as midi data by the synthesizers which then turn these values into frequencies.

The values which are actually turned into frequencies have been scaled to a less jarring range of possible pitches using a scale object and the transition between frequencies has been smoothed using the line~ object.

Finally, the frequencies are sent into a delay patch which utilizes two different controls. One is the static set of delay for each channel shown in the tapout~ object. Additionally there is a changeable integer value to add additional delay to the preset amounts in the tapout~.

Since I wanted to use a clear video to create an additional feedback effect (for an extra layer of delay using a randomly generated number value), I added a control to adjust the saturation levels. This is helpful as, depending on what is in frame, the change between values is too subtle to produce a recognizable variation in pitch. By manipulating the saturation, you can get around this issue. Additionally, this control can provide sweeping effects by changing the set of values sent to the synths.

The final product provides a crude sonic impression of the colors moving within the digital image.