NextGEN Gallery Ratings
NextGEN Gallery Ratings extends the extremely popular NextGEN Gallery plugin by adding ratings to your gallery images.
You can select which galleries to enable rating on, choosing between star ratings, “liking”, and up/down voting.
You can further control if only logged in users can rate images, and if they are limited to a single image per gallery, or all images. If you want users to rate, but not see results, there is an option to hide the results from users too.