如何获得每张图片的Facebook数量?

I have created a website (to practise my PHP+MYSQL skills)

The URL is http://rot47.net/picture-gallery/

The page allows you to upload any single photo quickly without registration. and I 've put a FB-like button on the page where the single photo is shown, such as http://rot47.net/share-picture/x

So, how could I make use of the statistics here? I want to create another single page that lists the popular photos 'liked-by-facebook' (sorted desc by FB-like numbers).

Is this possible? and how to do this efficiently? (for example, I have a million pictures, but I just want to know the top 100 pictures)

Here is the link, that will return you number of likes and shares in JSON format:

https://graph.facebook.com/?ids=http://www.example.com/