Affordances of Scan Processing Methods

An INTRODUCTION to SCAN PROCESSING This survey inquires about the affordances of historic and contemporary implementations of scan processing technology. Scan processing, also known as raster manipulation, refers to the separation and independent manipulation of the horizontal, vertical, and brightness components of a video image. It is often associated with the Rutt/Etra Video Synthesizer, which was designed in the early 1970s and used extensively by Steina and Woody Vasulka, Gary Hill, and other pioneering video artists. Scan processing differs from other methods of video synthesis or processing in that it does not generate a normal video signal which can be displayed on a standard analog or digital video monitor. Rather, it outputs three independent signals (horizontal sweep, vertical sweep, and brightness) which must be rendered on an XY display of some kind (oscilloscope, vector monitor, ILDA laser, etc). The look of the scan processing effect can also be emulated by digital video software. Scan processing relies on an input image or video, and thus does not include other XY image techniques, such as Lissajous figures or vector line art and animations. THREE METHODS of SCAN PROCESSING The three methods of scan processing covered in this survey utilize the following technologies: 1) Analog scan processing hardware such as the Rutt/Etra Video Synthesizer, the Dave Jones Raster Manipulator, or the LZX Cadet series modules with output displayed on an analog Cathode Ray Tube monitor 2) Digital software designed to produce a set of analog horizontal, vertical, and brightness signals to be displayed on an analog Cathode Ray Tube monitor, such as the REWereHere or Vector Synthesis scan processing patches for Max and Pure Data. 3) Software which emulates the Rutt/Etra, scan processing, or Z-displacement effect entirely in the digital video domain, such as the v002 Rutt/Etra Quartz Composer plugin, the Rutt/Etra-Izer, or a number of filters and plugins for other softwares. ABOUT AFFORDANCES "Affordances" is a term from interface design which describes the various possibilities an object suggests or offers to its users. These possibilities may or may not be part of the object's intended design, and may also be specific to certain users. For example, a coffee mug is designed for drinking a hot beverage, but just as easily I can scoop dry rice out of a bag, hold a dozen pens ready for writing, or elevate another object such as my laptop off the table by using it. See: https://en.wikipedia.org/wiki/Affordance