In an effort to keep people from incorrectly reusing or repurposing images found on its image search tool, Google has added new options that let users filter results by usage rights. Users can now filter photos by whether they're available for reuse, commercial reuse, reuse with modification, or commercial use with modification.
Google is including a variety of licensing methods including Creative Commons, GNU Free Documentation license, and items that are in the public domain. Its system for determining the rights on various shots is not foolproof though, and as such the company is recommending that those who are interested in republishing or reworking any of the images check with the content owner first (if possible).
What's likely to be a long-term effect of supporting license filtering is that Google's image index becomes far larger than it is right now. Some content owners who have chosen to block its indexing to keep others from easily reusing their photos may think twice; with these new filters there's at least some semblance of care and control, even if Google is basing that off information from a photo's metadata.
It's also a signal that Google is paying more attention to the rights of user content, although the filtering is still something that's tucked away in the advanced settings of the search tool, and not something users have to check off before even beginning a new search.
Google has not yet rolled out license filtering to any of its other properties. Sites like Google Books and Video could be next. In the meantime, there are several search tools that let users quickly seek out images that can be reused and remixed including the Creative Commons search engine, Flickr, Blip.tv, ArtistServer, The Internet Archive, Wikihow, and Wikipedia.