Not really. Some gallery making programs like Arles will generate thumbs for you, but the quality is never as good it should be inaccordance with today's TGP standards.
If I need one of a particular size to submit with, it's always done by hand. The quality of your thumb is paramount to your traffic return.
Guys making big money with thumb based TGP's can tell you where on the page they will be... because they have the thumb processed dialed.
Tested and tweaked and tweaked some more.
Always best to cut them, nice and crisp with some color or image correct as need be.
I manually crop my thumbs using Photoshop. You can create an action in Photoshop for batch processing of thumbs. Depending on what you are using the thumbs for, some people use Arles or ThumbsPlus for batch processing.
thumbnailz
Linear Mode
