Matt Black : Pixi App - Talk - Splice Festival 2017

Matt Black : Pixi App - Talk - Splice Festival 2017 from Splice Festival on Vimeo.

Pixi – A Granular Visual Synthesiser

Pixi is an iOS app in development, a collab between Coldcut and coders Paul Miller, Amaury Hazan and Chris Rice. Pixi is termed a ‘granular video synthesiser’. It was first prototyped from round 2011 in Quartz Composer as Granul8…making it a qtz meant it could be loaded into modular VJ software VDMX and used for VJing. We then realised it would make a great touch controlled app.

In audio, granular synthesis involves using a small part of a Audio sample, the ‘grain’ as the basis for synthesis. The part of the sample used for the grain can be shuttled up and down the waveform and can be of varying size. By analogy, Pixi uses the concept of Granular Video Synthesis: in Pixi , video synthesis is based on a small part of an IMAGE, typically a photo, and this source sample can be taken from different parts of the image, and change size and aspect ratio. The rectangular sample is combined with a mask image (e.g. circle, star) to yield a Brush. The Brush is then used to draw patterns. If the sample is the size of the entire source picture, then Pixi can function as a basic picture processing/fx app. But there are many ways in which Pixi can produce surprising and interesting visual results from manipulations of the Brush. Particle systems, such as multiple Brushes, are an enhancement to the program which was a bit like going from a mono to a polyphonic synthesiser. Pixi has a sophisticated Patch Matrix, like a modular synth in which Control params e.g. Acceloromoter, LFO, touch control, Perlin noise are assigned to Synth params e.g. brush size, position, alpha, feedback. This enable an infinite number of patches to be constructed, and favourite ones saved. In Spring 2017 we release a player version of Pixi to accompany the Bogus Order album. This provides 10 presets tracked with music from the album.

Work is continuing on Pixi with Amaury Hazen from BCN now in pole coding position. We would like to work with visual artists to take their work as images into Pixi and then design presets based on these images, as a ‘Visual remixing’ process. These could be inapp purchases and so visual artists could earn from Pixi too.

coldcut.net/pixi