Incorrectly positioned coordinate system

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   Hello 

I have a PDF and want to add additional text boxes. 
The document is scanned. 
Unfortunately, the coordinate system is not correct. 
If I want to write something on the null coordinates it is in the middle of the page and not, as in all other PDFs top left. 
I need help =)

Thanks

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Goldstick Members Profile Find Members Posts Beginner Joined: 11 Jun 14 Status: Offline Points: 2	Post Options Post Reply Quote Goldstick Report Post Thanks(0) Quote Reply Topic: Incorrectly positioned coordinate system Posted: 11 Jun 14 at 12:02PM
	Hello I have a PDF and want to add additional text boxes. The document is scanned. Unfortunately, the coordinate system is not correct. If I want to write something on the null coordinates it is in the middle of the page and not, as in all other PDFs top left. I need help =) Thanks

Ingo Members Profile Find Members Posts Moderator Group Joined: 29 Oct 05 Status: Offline Points: 3529	Post Options Post Reply Quote Ingo Report Post Thanks(0) Quote Reply Posted: 11 Jun 14 at 6:20PM
	Hi Goldstick, it depends on the values you're using: The media- or cropbox-dimensions or pagewidth/-height (better using the boxes). And first of all (before to calculate the new positions) you should use SetOrigin. To set the MeasurementUnits could be helpful, too. Another point: A pdf document could be made with rotate-functionality - so your calculated positions are rotated, too. With QuickPDF you can check if there's a rotation. The coordinate system is inside the pdf document and it can be different but with the things i've told before this shouldn't be a problem. Have a look here: http://www.debenu.com/docs/pdf_library_reference/MeasurementAndCoordinateUnits.php Please read detailed at SetOrigin, GetOrigin and SetMeasurementUnits. Cheers and welcome here, Ingo
	Cheers, Ingo

AndrewC Members Profile Find Members Posts Moderator Group Joined: 08 Dec 10 Location: Geelong, Aust Status: Offline Points: 841	Post Options Post Reply Quote AndrewC Report Post Thanks(0) Quote Reply Posted: 16 Jun 14 at 7:25AM
	The most likely issue is that the co-ordinate system needs to be reset back to default settings. Add a call to QP.NormalizePage(0); once per page before drawing the text. Many PDF's leave the corrdinate system in an unknown state because they know the current state but don't bother to reset it at the end when they are finished. When you add text to the end of a content stream the coordinate system is set by the original PDF and that is what you are seeing on some PDF's. NormalizePage will wrap a savestate / restorestate around the content streams thus making it safe to draw text. Andrew.