[cflsystems]

Go to admin / tools / summary and check on the link for php details (down the page where environment info is). On the page that shows search "gd", you should see somehting like this


gd

GD Support enabled
GD Version bundled (2.0.34 compatible)
FreeType Support enabled
FreeType Linkage with freetype
FreeType Version 2.2.1
GIF Read Support enabled
GIF Create Support enabled
JPEG Support enabled
libJPEG Version 6b
PNG Support enabled
libPNG Version 1.2.10
WBMP Support enabled
XPM Support enabled
XBM Support enabled

If you don't see it there is no GD library installed, if you see it note the image types enabled. In 4.4.5 on the settings page you can specify the image type to be used when generating images