Description
The miniature refers to historical video rasterizers, which, in the 1970s, artists used to transform video signals in real time.
As in the original “scan processors,” here the image becomes a material susceptible to modulation, distortions, and shifts that imitate three-dimensionality. The work is a contemporary, original interpretation of these technologies: exploring how an algorithm can reproduce the analog sensitivity of early video experiments.
CRT RAS is ideal for field work, allowing reality to be scanned using a mobile device.
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A bit of history, scanning, field work
“Scan processor” is the name of a family of devices—video signal rasterizers—developed in parallel by authors drawing inspiration from each other. For example, the “Rutt/Etra Scan Processor” was designed and prototyped in 1972-73 by Steve Rutt, Bill Etra, and Louise Etra, working with funding and resources from the New York State Council on the Arts (grant), WNET Thirteen Laboratory New York, and their own savings. Similar devices were already circulating in more or less ephemeral hacker-art circuits at the time, such as “Scani-Mate” by Lee Harrison and Nam June Paik, or the “Paik/Abe Scan Modulator” by Shuya Abe and Nam June Paik. Abe and Paik’s design, interestingly enough, was assembled through a visionary combination of commercially available circuits, with its Achilles’ heel and yet characteristic feature being image interference from the power supply module (this interference proved extremely difficult to intentionally simulate). The devices differed in many functions, but their common denominator was the idea of influencing (modulating) the television signal using various generators, envelopes, and mechanisms for extracting a signal parameter and applying it to change the value of another parameter. All of this strongly resembled modular audio synthesizers, and some of the “scan processors” (e.g., the “Rutt/Etra Scan Processor”) could communicate with the outside world using protocols typical of contemporary modular audio systems (primarily via control voltage). Although the designs of these devices were often created by creative individuals with recognizable, original achievements, “scan processors” were popularized within the community through artistic “proxies” who experimented with them as instruments. The most widely distributed works created using them include those by Gary Hill and the duo The Vasulkas (Stein and Woody Vasulka). The duo The Vasulkas are credited with creating the “Rutt/Etra Scan Processor” configuration, which allows for modulation of the vertical position of video image lines with the brightness of these lines, creating an effect suggestive of three-dimensionality.
“Scan processors” are, from my perspective, extremely interesting devices-instruments, transforming mental figures derived from designing and working with electronic musical instruments into a visual context. Therefore, I sought to understand their functioning and the specifics of their operation in specific cultural contexts as deeply as I could, without limiting myself to applications.
“Scan processor” designs from the 1970s were based on analog technologies, while later, often virtual, designs were based on digital technology and software. Such digital emulations, constantly rebuilt by new creators, also circulate between the worlds of hobby applications, related to art and creation, and the reconstruction of historical technologies. At the WRO Art Center, we have also repeatedly used such emulations in various activities – particularly important in this context were our group installations from the “On the Silver Globe” series, implemented since 2012. “On the Silver Globe II” and “On the Silver Globe III” contained (among many other components referencing art history) digital emulations of the pseudo-three-dimensional effect developed by The Vasulkas.
All digital emulations of “scan processors” that I know of, in particular the aforementioned pseudo-3D effect, are based on the same mechanism: a two-dimensional image (texture) is applied to a mesh, the vertices of which are moved using color values or simply brightness values taken from texture locations with coordinates corresponding to those vertices—this is a standard technique in 3D computer graphics (so-called “bump mapping”—a technique typically used for static images and, for example, simulating minor irregularities in three-dimensional objects, such as cracks or roughness). This approach seems optimal from a technical point of view, consistent with the architecture of modern graphics processors. Perhaps the best “scan processor” emulations, based on the idea described above and characterized by the deepest understanding of the subject, were designed and programmed by Anton Marini (in collaboration with Bill Ettra) and Ramsey Nasser. These are, respectively, extensions for the VDMX and Hydra electronic image experimentation environments (in the latter case, the vertices are essentially virtual – however, the overall idea of the mechanism’s operation is similar to that described, and Nasser presents his approach in detail in the article Livecoding Scanlines on the GPU).
While appreciating the new capabilities and efficiency of modern incarnations of “scan processors,” I have long been interested in building my own rasterizer algorithm that would create images that more closely reflect the historical combination of processes occurring in analog electronics and CRT screens (although also potentially subject to manipulation using mechanisms available thanks to modern imaging technologies). Previous experience with designing an algorithm used, among others, in In the miniature “CRT Hix” and the performance “Silver Moon, Blue Planet, Blue Note,” I was able to formulate a generalized procedure, an approach at the level of system architecture design. However, as with “CRT Hix,” I aimed to achieve this goal not through stylization, but by managing the computational mechanics in a way that avoided “bouncing off” from the specifics of GPU programming.
The final important characteristic of the Miniature stems from the fact that, as with “CRT Hix” (and to a greater or lesser extent, this applies to all miniatures), a very important parameter for me in “CRT Ras” is the ability to transfer work with the designed system into the field, to scan the environment ad hoc—using a mobile and possibly inexpensive device taken outside the studio, workshop, or laboratory.
Technical documentation
Parameters passed via URL
- amp 0.0 … 1.0; default 0.5; image brightness amplification
- clr 0 or 1; default 0; disables/enables color mode
- famo user | environment (or env); default user; [facingMode] allows forcing the use of the front (user) or rear (environment) camera on devices equipped with dual cameras (most modern mobile devices)
- fld 0 (none) 1 (mirror reflection) 2 (clamp) 3 (repeat); default 0; wrapping of lines that go beyond the top/bottom edge of the image
- gui 0 or 1; default 1; hides/shows the graphical user interface panel
- h vertical camera resolution
- lang en or pl; default en; sets the interface language (additional languages can be added)
- midiinport disabled by default; MIDI port number for external control of Miniature (receiving messages)
- mirror 0 or 1; default 1; disables/enables mirroring of the image from the capture device (usually a camera)
- pdd 0.0 … 1.0; default 0.5; (padding) line density
- pointer 0 or 1; default 1; hides/shows the mouse cursor
- prc 0.0 … 1.0; default 0.5; (precision) precision of the interline simulator
- vo 0.0 … 1.0; default 0.5; (vertical offset) vertical shift of the entire image up or down
- w horizontal camera resolution
- worker 0 or 1; default 0; allows blocking the browser’s built-in mechanisms that suspend the program when the window is not visible
- wrp 0.0 … 1.0; default 0.5; (warp) range and direction of modulation for the line offset point based on brightness
- ws address; disabled by default; enables and sets the address (usually localhost:9001) for WebSocket communication (allows external control of Miniature and customization)
- xws address; disabled by default; enables and sets the address (usually ws://localhost:9001) with protocol specification for WebSocket communication (allows external control of Miniature and customization)
Messages passed via WebSocket
Messages to which Miniature responds
- amp 0.0 … 1.0; normalized value of image brightness amplification
- color 0 or 1; default 0; selection between monochrome and color modes
- offset 0.0 … 1.0; default 0.5; normalized value of vertical image offset (neutral position = 0.5)
- padding 0.0 … 1.0; normalized line density
- precision 0.0 … 1.0; normalized value setting the system’s precision (low precision results in a characteristic “analog” glow)
- warp 0.0 … 1.0; normalized value of the warp degree (neutral position = 0.5)
- wrap none | mirror | clamp | repeat; default “none”; selection of the method for “wrapping” the image at the screen edge
Messages sent by Miniature
N/A
MIDI
Messages to which Miniature responds
- CC 000 on any channel line density
- CC 001 on any channel image brightness amplification value
- CC 002 on any channel warp degree value
- CC 003 on any channel value setting the system’s precision (low precision results in a characteristic “analog” glow)
- CC 004 on any channel normalized value of vertical image offset
- CC 005 on any channel 0 or 1; default 0; selection between monochrome and color modes
- CC 006 on any channel 0 (none) | 1 (mirror) | 2(clamp) | 3(repeat); default 0 (none); selection of the method for “wrapping” the image at the screen edge
Messages sent by Miniature
Not applicable
Communication with MaxMSP
Messages to which Miniature responds
Not applicable
Messages sent by Miniature
Not applicable