Paul Hertz • Seven Time Cycles

Bent Rainbow Evolution: imagescan04.html
Summer Storm: summerstorm.html
Sintra: sintra.html
Puente del Arzobispo: puente.html
XOXO: xoxo.html
Tinglado: tingle.html
Islas: islas.html

These seven works were created using my own software, GlitchSort, written in Java using the Processing library. They run in a web browser using processing.js and JavaScript. They are intended as slow animations, where change is sometimes barely perceptible (as in Islas and Bent Rainbow Evolution): the single exception is XOXO, which speeds along to reveal the symmetries that emerge from the transformation that drives the animation. The animations are cyclic: at each step in the animation, all the pixels are shifted a short distance along a space-filling curve, the Hilbert Curve.

The animated images are visualizations of audio signals. Typically, I combine three different audio signals, one for each RGB channel. The variations in color arise from the frequency relationships of the audio signals. In Tinglado I have reduced the three signals to black and white. In all the images except XOXO the signals were written along the same space-filling curve that is used for the animations. In XOXO, the signals are written along a zigzagging diagonal. The Hilbert curve and the zigzag scan allow me to map a one dimensional audio signal in time to a two dimensional image in space. It also works the other way: GlitchSort can turn images into audio, in live performance or recorded video.

The signals I use could be considered as low frequencies, below the threshold of hearing, at least in terms of the way they are generated and fill space. Low frequency sound is visualized as slowly changing color. In Tinglado, however, the frequencies are higher, and the visualization has finer detail. In Tinglado, shifting pixels produce shimmery artifacts that seem to float on the underlying pattern. Often I use frequency ratios based on the Fibonacci and Lucas series (such as 0.89 Hz, 1.44 Hz and 2.33 Hz), which are closely related to the Golden Mean. Other times I use musical chords from the Western diatonic scale.

These work evolved from several long-term concepts in my art practice. Exploring the correspondence of sound and visual art dates back some four or five decades, to generative systems that I continue to use for intermedia composition. I have also been fascinated by patterns, and the visualization techniques in these seven pieces have been particularly rich sources of patterns. Less evident is my concern with noise and error. These images were produced by (mis)using a Fast Fourier Transform to propagate resonant frequencies from small variations in "seed" images. The results in this case were pushed towards smooth variation, but they can also produce glitchy noise. Finally, I was seeking a sense of time passing in these works, passing at a rate that one might need to live with these works to see them change. Towards this end, except in XOXO, I have written the software to jump back in at approximately the same spot it left off when the page is reloaded.