How to increase resolution of image?

[Paul Moen]

Can the resolution of the image created by saveWebImage(); in php mapscript be changed to
something other than 72 pixels per inch?

I have read the how-to/ pdf output which talks about creating an image at 150 dpi for a 8 x 8 map at
1200 x 1200 pixels.  All this gives me is a image that is 1200 x 1200 pixels at 72 dpi which is a
16.67 x 16.67 inch image.

What part am I missing that gets me the 150dpi resolution?

reference about how to/ pdf output from following web address.
http://mapserver.gis.umn.edu/docs/howto/pdf-output/#render-png-views-at-a-suitable-
resolution

Paul