How to display .eps file in the SharePoint picture library?

There is no out of the box SharePoint support for previewing those files in an library view. You'll have to go custom code or third-party if you want to be able to see these images in-browser. Just Google 'sharepoint eps preview' and you can find several results.

On a minor note, you can change the icon for file formats away from the blank one using these instructions from MS. For 2013, just use /15 instead of /14.