What is wrong in this resize() function?

[eluser]chefnelone[/eluser]
Near to find the problem

There's no problem with the resize function.

It is a problem of my local server, because I uploaded the site to my hosting and it works fine.

I use MAMP for running my site in my localhost.

The problem should be in php.ini ??
I have:
upload_max_filesize = 32M;

What else could be??