Finding extents of printable entities

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   I was wondering if anyone has ever used (or if it's even possible) the QuickPDF library to fid the extents of visible entities of a PDF document.

What I am trying to do is merge multiple pages together but only taking the sections with visible elements from each page. Our existing code base uses another library to vectorize the PDF to an image, and then the image is scanned line by line for any pixel that isn't of the background color.

I'm thinking there has to be an easier way of detecting the extents of entities in a native format, but I have yet to find a method that works.  (I thought I was close with http://www.quickpdflibrary.com/help/quickpdf/GetPageBox.php, but it always returns the full extents of the PDF [page width/height])

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jacob.hoover Members Profile Find Members Posts Beginner Joined: 06 Mar 08 Status: Offline Points: 4	Post Options Post Reply Quote jacob.hoover Report Post Thanks(0) Quote Reply Topic: Finding extents of printable entities Posted: 24 Mar 10 at 2:24PM
	I was wondering if anyone has ever used (or if it's even possible) the QuickPDF library to fid the extents of visible entities of a PDF document. What I am trying to do is merge multiple pages together but only taking the sections with visible elements from each page. Our existing code base uses another library to vectorize the PDF to an image, and then the image is scanned line by line for any pixel that isn't of the background color. I'm thinking there has to be an easier way of detecting the extents of entities in a native format, but I have yet to find a method that works. (I thought I was close with http://www.quickpdflibrary.com/help/quickpdf/GetPageBox.php, but it always returns the full extents of the PDF [page width/height])

jacob.hoover Members Profile Find Members Posts Beginner Joined: 06 Mar 08 Status: Offline Points: 4	Post Options Post Reply Quote jacob.hoover Report Post Thanks(0) Quote Reply Posted: 25 Mar 10 at 4:04PM
	I'm seeing a few looks but no comments. Is my question not clear enough, or is there no way that anyone knows of to get the extents of visible entities in a PDF? Thanks, Jacob

Paddy Members Profile Find Members Posts Beginner Joined: 24 Mar 10 Status: Offline Points: 8	Post Options Post Reply Quote Paddy Report Post Thanks(0) Quote Reply Posted: 25 Mar 10 at 4:12PM
	Can you provide more info on what you mean by "visible entities" exactly?

jacob.hoover Members Profile Find Members Posts Beginner Joined: 06 Mar 08 Status: Offline Points: 4	Post Options Post Reply Quote jacob.hoover Report Post Thanks(0) Quote Reply Posted: 25 Mar 10 at 5:39PM
	For a more simplified view, assume I have a single page PDF with only a single line drawn on it from one inch in from the left side of the page and one inch down from the top of the page, to seven and a half inches in from the left side of the page and ten inches from the top of the page. Given that, I would like to get the extents of the page and have this return a rectangle with the top left point being (1,1) and the bottom right point being (7.5, 10).