I've been printing some ANSi art lately, and figured out I would post something about it.
All pieces have been printed at a digital photo printing kiosk using 4R format (which translate into a size of 4" × 6" or 102 × 152 mm and a 3:2) ratio.
I had to make two batches in order to get the desired results:
For the first batch, I just printed the 16 colors PNG output from Ansilove to see how it would look like, and I can tell you it didn't turn out very well: the aspect ratio was not preserved (which I expected) and the printed material had dull colors.
For the second batch, I added some extra black borders around the pictures in order to get a 3:2 ratio and also changed the color profiles to use one optimized for printing: it went much nicer this time, providing pictures with correct aspect ratio and more vivid colors. It's still not 100% perfect as the picture still has to be resized by the printer, causing some artefacts on color blocks, but overall the result is more than satisfying and it will do, at least for now.