I went through the source code, and I don't see any reference to any code in there that converts the jpg to png. It's creating the image from scratch at one point, but it maintains the mime type while doing so.

I'll download a copy of it on my server, and test it out, nevertheless.

Also, you're using it on a forum? Or a blog?

EDIT: According to the source, it should have been fixed. Ref: http://code.google.com/p/timthumb/issues/detail?id=28
Lifetalk Reviewed by Lifetalk on . timthumb problem Hey, I had this scrip from sometime now in the first skin, but it didn't work on the second so i had to get another, but This one is killing my site! When I add a JPG image it resizes it and convert it to .PNG which is much larger and heavier, could somebody please make it keep the images as they are? jpg to jpg, png to png...etc? Thanks a lot! <?php /* Rating: 5