Google Image Search has recently add another filter option to the mobile version of image search. Under the search box, it gives you quick filter links to filter for the latest images, clip art, GIFs, colors and copyright. It’s possible to drag the bar to the left to show more color filtering options. You’ll find an option for filtering for “labeled for reuse” at the end of the filter options.
You can click on one of the color filters – which I selected orange – and your results will be filtered based on your selection:
This new filter option hasn’t been officially announced by Google yet, but it’s being rolled out int he mobile image search results.