ASCII Art

At 03:05 AM 12/30/2007, ard at p850ug1.demon.co.uk wrote: There were many approaches, of course. There were typewriter artists in the same style, years before teletypes. Many old RTTY images were built by hand. Certainly many RTTY images were ported to computers and are still passed around today. If you have kids on MySpace, you'll see that ASCII art is still very popular when posted as comments on your friend's web pages. Later computer-generated pictures were certainly automated through several sorts of scanning processes and subsequent assignment of grey to chars. For example, with any early computer that could drive a teletype and digitize a crude value from a phototransistor mounted on the print head, you can feed a photograph through the print roller, "print" nothing, read the values and "scan" the image. The choice of chars could include schemes for overstrike - sending a line with a carriage return but without the line-feed, and overprinting to make new one-char-space greys. I talk about this on my page http://www.threedee.com/jcm/aaa/ . A long time ago I wrote a filter to translate overstrike ASCII files into Adobe Illustrator files. This gave a path to printer-independent overstrike, choice of fonts, and direct rasterization of the image via PhotoShop, which can read the AI files. Fully automated conversion of old ASCII art to bitmaps can be tricky. There are other feed-control characters explicit or implicit in some of the original files, such as form feed and vertical tab. Some ASCII art came with its own printing program to interpret the image data. They come in all rotations. As you can see in the Einstein example on my page, the chars used to print Albert are "upside down". Some images are portrait, others landscape. Some are assembled of several strips or even just partial strips, taped together. More subtle infidelities happen when the font's glyphs don't exactly match the original. Then there's the huge realm of ANSI art from the late 80s / early 90s, using the VT-100 / PC-ish conventions for positioning the cursor on the 80x24 screen, erasing, refreshing, or animating, often passed around on BBSes. - John