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Under The PDF Hood »

[13 May 2010 | No Comment | ]

I came across an interesting issue with PDF Text fields while debugging a file this week. We were sent a 2 page document created with iText, containing some text fields and we were displaying both pages with text fields containing identical values – they appear different in Acrobat. Obviously Acrobat is always right (even when it disagrees with the PDF specification) so we dug deeper to see what was going on…

Under The PDF Hood »

[10 May 2010 | No Comment | ]

One of the reasons that the PDF file format is so popular is that it embeds a large amount of font information in the PDF file, so that it can accurately reproduce the display as intended on any machine. It will not turn your beautifully crafted 12 page document into a horribly mis-formatted 14 page version, as Microsoft word does, if it cannot find all the fonts.

Under The PDF Hood »

[9 Apr 2010 | No Comment | ]

Inside a PDF is a Postscript stream of commands which describe the page – they draw the text, images or shapes. You can extract this stream and look at it directly. It looks like this -I have added comments in brackets after each command to explain.