PHP Print Text on Image - Center Alignment Fix

A short job for someone who know PHP - please give me your best price - files attached.

I have some code that prints text onto an image using php

you can see it at http://electrikpublishing.com/ebooks/demo/example.php

the query it with these variables - 'title' and 'author'

I need some help to remove the small border on the left and near top as this is currently coming out on the image.

Also, I want to center the text - rather than left aligned. I need this for both author and title. The y positions are generally ok - but may need to edit this in the future myself.

Some help here..

http://php.net/manual/en/function.imagestring.php

Files attached.

Thanks
Nick