Dimensions of a pdf page

I'm adding a watermark to pdf document, but position 0,0 is the bottom left-hand corner. I need to put the watermark at the top left-hand corner.

Q: Using version 8 of ColdFusion, how do I determine the page size, or how can I position the watermark at the top?

Update: I think I should be looking at action="a开发者_Go百科ddHeader". Using leftmargin="0" and align="left", I was able to move it to the left, but is there a way to move it to the top?

Ray Camden has a blog entry about finding out the size and orientation of PDF pages.

http://www.coldfusionjedi.com/index.cfm/2008/8/12/Getting-page-orientation-and-size-from-PDFs