I'm sure any of you can "out-logic" me, but I would have thought that "whether they may have been duplicated elsewhere" DOES matter.
Compression and quantization artifacts are ubiquitous in digital imaging. Almost every digital image contains them to one degree or another. And in most digital images, such artifacts can be amplified. Are they as noticeable elsewhere in 3D texture-mapped synthesized images? I don't know.
Saying they are "characteristic" means they can be identified easily regardless of context. A fingerprint looks like a fingerprint whether it's on a glass tabletop or on a leather seat cover.
I sympathize with your desire to satisfy your friends, but don't be duped into accepting their proposed standard of proof as reasonable. Saying that it can't be a quantization artifact until some other similar example is shown is pure distraction. To imaging experts there is no question what the artifacts are.
|