Is File Upload class creates unique file name when encrypt_name set true?

Thanks @jreklund & @Dave friend, I finally ended with prefixing auto-increament id along with uuid to the uploaded file name. I worried about setting the original file's extension with filename, but CodeIgniter automatically preserves the original file's extension even I didn't mention it in $config['file_name'] parameter.

"Everything is Possible in the world of Computers"