I am trying to retrieve Images from Image Library using Rest API from a mobile device (hence, no cross site calls).. 

I am using this approach (https://stackoverflow.com/questions/16893729/how-to-retrieve-image-files-from-sharepoint-image-library-list-through-rest-ap ) to get file binaries directly, not the server relative URL to avoid cross site requests.

I am able to get the images, however since I want to create a picture gallery on my phone, I want to download thumbnails first and then full image once you click on thumbnail.

Is there any way to get thumbnails using Rest API?