It's most likely some sort of vinyl wall decal, they're available in everything from a simple flower to whole-wall designs. That particular picture may have been custom, but there's lots of places online that offer something similar. Here's one from the first page of Google links that seems to have a broad selection. posted by pupdog at 7:11 AM on August 6
Digital inkjet print onto a high-quality vinyl with a matte or semi-gloss overlaminate (I suggest matte), die cut to the exterior shape. Depending on the size, it may need to be seamed. Check your MeFi mail. posted by Optimus Chyme at 7:48 AM on August 6
It's also possible an actual artist was involved who drew the images on the wall. posted by Mitheral at 8:13 AM on August 6
There's some more views on the designer's site (click Projects at the top, then Rudy's Mural [the first one] on the left). As awesome as it would be, I don't think it would be cost-effective to have an artist paint at that level of detail on a wall - the images are basically etchings. Also looking at some of their other work, and the fact that this mural is referred to as an "installation," I'm pretty sure that this is a digital composite of some sort, printed onto giant wall decals (maybe with some additional painting incorporated on the walls). posted by LolaGeek at 8:46 AM on August 6
http://homokaasu.org/rasterbator/
That's a site that will enlarge images to mural size. This wall art looks similar to some that I have seen done with the rasterbator posted by Melsky at 8:48 AM on August 6
Working link posted by Melsky at 8:50 AM on August 6
Looks like a wall decal. I see them at art stores around here, and I think they're basically just wall-safe stickers. posted by tybeet at 9:20 AM on August 6 [1 favorite]
They could also be drawn using a projector. posted by occidental at 9:52 AM on August 6
I've done something similar by printing out on large format premium photo paper, piecing it together and pasting it on the wall with a wet mount, similar to wallpaper. posted by Foam Pants at 10:29 AM on August 6
posted by Ladybug Parade at 7:08 AM on August 6