Well we had an instance of this in our photoclub. One member took several pictures (off the net, from National Geographic amongst other sources) and cropped a bit here, a bit there, mirrored it and then submitted to the internal competitions. He walked away a decorated (trophies and ribbons) man, being uuuhhhhed and ahhhhed by all for his superb photography. One competition I helped judge he photographed a mural and we all hummed and haaaa'd on how the dickens he made this in Photoshop ... then I saw the ledge of the wall; so I pointed out he did no such thing, but handed in a photograph of a mural; too late, he won the competition (it was a "creativity" competition. Well next year someone else did the same thing, so then the image was thrown out. However, the former character submitted another "painting" as his own .. did not even bother to change the title of the painting. That is when we found out about it. Yours truly did a search on the net, and voila: the wallpaper came up. This is something that was FOR SALE for people who liked it. Like as in a print for example. Needless to say the club executives asked some rather pertinent questions, and this character is no longer a member of our club.
I used Google chrome to find duplicates. If ever you wonder if someone else is using your stuff, do a search with Google chrome (there is a utility that does a web search based on the image alone, not even the title - i think it is called tineye).
Anyone using someone else's art to stuff his pockets is guilty of stealing. That is all there is to it from my point of view.
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