Facebook API – How do I get a Facebook user’s profile image through the Facebook API (without requiring the user to “Allow” the application)

Simply fetch the data through this URL:

http://graph.facebook.com/userid_here/picture

Replace userid_here with id of the user you want to get the photo of. You can also use HTTPS as well.

You can use the PHP’s file_get_contents function to read that URL and process the retrieved data.

Resource:

http://developers.facebook.com/docs/api

Note: In php.ini, you need to make sure that the OpenSSL extension is enabled to use thefile_get_contents function of PHP to read that URL.