AJAX Voting for the Image Gallery..

Hi All,
I just saw this wonderfully made site (https://worldwidephotowalk.com/peoples-choice/). As you can see it has all the images laid down smoothly as a grid and each image has an ajax enabled star rating below it. Looking at the source, I figured the ratings are from the GDSR plugin.
Great!
But can anyone figure out, how the whole thing can be achieved? I couldn’t figure out how the GDSR is applied to individual images! Looks like a custom made plugin for the site… Any ideas people?
I’d love to have this sort of gallery for my site too!