Old ASCII Protocol Avatar Question

Question

For anyone that remembers the protocol Avatar, (I'm pretty sure this was it's name) I'm trying to find information on it. All I've found so far, is that it's an ANSI style compression protocol, done by compressing common ANSI escape sequences.

But, back in the day, (The early 90's) I swore I remembered that it was used to compress ASCII text for modems like early 2400 baud BIS modems. (I don't recall all the protocol versions, names, etc from back then, sorry).

Anyways, this made reading messages, and using remote shells a lot nicer, due to the display speed. It didn't do anything for file transfers or what not, it was just a way of compressing ASCII text down as small as possible.

I'm trying to do research on this topic, and figured this is a good place to start looking. I think that the protocol used every trick in the book to compress ASCII, like common word replacement to a single byte, or maybe even a bit.

I don't recall the ratio you could get out of it, but as I recall, it was fairly decent.

Anyone have any info on this? Compressing ASCII text to fewer than 7 bits, or protocol information on Avatar, or maybe even an answer to if it even DID any of the ASCII compression I'm speaking of?

Answer 1

If I remember correctly, the Avatar compression scheme was some simple kind of RLE (Run-Length Encoding) that would compress repeated strings of the same characters to something smaller. Unfortunately, I don't remember the details either.

Did you check out AVATAR on Wikipedia?

Answer 2

Wikipedia has something about AVATAR protocol:

The AVATAR protocol (Advanced Video Attribute Terminal Assembler and Recreator) is a system of escape sequences occasionally used on Bulletin Board Systems (BBSes). It has largely the same functionality as the more popular ANSI escape codes, but has the advantage that the escape sequences are much shorter. AVATAR can thus render colored text and artwork much faster over slow connections.

The protocol is defined by FidoNet technical standard proposal FSC-0025.

Avatar was later extended by in late 1989 to AVT/0 (sometimes referred to as AVT/0+) which included facilities to scroll areas of the screen (useful for split screen chat, or full screen mail writing programs), as well as more advanced pattern compression.

Avatar was originally implemented in the Opus BBS, but later popularised by RemoteAccess. RemoteAccess came with a utility, AVTCONV that allowed for easy translation of ANSI documents into Avatar helping its adoption.

Also:

• FSC-0025 - AVATAR proposal at FidoNet Technical Standards Committee.
• FSC-0037 - AVT/0 extensions