Unless I missed it, I haven't noticed any comments which include information about U.S. and INTERNATIONAL COPYRIGHT LAW(S).
As an artist, after I create my original artwork (a painting, a drawing, a photograph) -- whether it is digital or not, I AM THE COPYRIGHT OWNER by default.
From what I understand (and, I may be wrong?), nobody has the right to alter or reproduce my artwork without my express, written consent. If they do, they are breaking U.S. Copyright laws!
Imagine, for example, what would happen if IBM degraded the quality of every web-occurance of Coca Cola's logo, or Apple Computer's logo! The 'stuff' would hit the fan, for sure!