Here it is folks:
This site lets the owner of an image find out where and how their images are being used. It also lets web designers locate the owner of a photograph to contact them about licensing.
If you link back to an image by right clicking and copying the URL (inline linking), then you are OK, since the software would only track the image back to the original website. And in any case, there seems to be no plagiarism involved when you do inline linking as this article on wikipedia tells us.
However, if you download an image into your computer, play around with it a bit (resize, crop etc) and put it back online - then you are toast! Or could very easily be if the owner of the image were to set their mind on checking on things.
I am not sure if this would also work with highly processed and manipulated images, however I would err on the side of caution and stay away from such practices altogether. For one thing, regardless of whether you get caught or not, it is not the right thing to do. Second, why take the risk when there are literally millions of images online, which you can use under the proper creative commons licenses? Read more on where to find them here.
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