Yes a reverse image search.
This cool website TinEye allows you to upload an image or link to an image on the web and find out everywhere it’s been found on the web.
This site was first brought to my attention by Danielle Parent in a discussion about images being stolen and used by other people to make money.
Being the eternal optimist, I thought it would be a great way to find out if an image really is free to paint and to find out who the original artist is to request permission to paint.
Here’s an example. I’ve found a wonderful picture on PMP ( I know they would never cheat, but it’s fun to look). I uploaded the image and clicked on search.
So I tested another image of an underwater ocean. This time I put the URL link into TinEye and clicked on search. Here’s the results:
There were 64 results and on the second page I found the one with the most pixels, probably the beginning.
Of course it doesn’t hurt to make sure your pictures haven’t been used by someone else.