The first thing you'd need to do is fix your script; what's shown above won't compile. (As to being a hack, you have nothing to worry about: I've seen much, much worse code before. :)

### This will be a syntax error: "in" is a bare word
$page->mediabox(8.5/in, 11/in);

### This will cause several types of syntax errors
$ImgFile, .1/in, .1/in, 8.4/in, 10.75/in );
[download]

Otherwise, the suggestion by olus is a pretty good one: Image::Magick is excellent for any kind of image handling/processing.

-- 
Human history becomes more and more a race between education and catastrophe. -- HG Wells