ANSI art was almost always published as sequences of text and MS-DOS compatible escape codes. That's what an .ANS file is, and how it was transferred over the modem in an interactive session.
And sure, this is art, but it's basically just a file conversion. ffmpeg has been able to output ANSI since at least 2010 [1]
1: https://ffmpeg.org/doxygen/trunk/ansi_8c_source.html