Learning about PDF

The PDF file format is very useful and well-documented, but it is also quite complicated and it does not work how most people imagine. It is structured very differently from a Word or Excel document. Most of the time, this is not an issue – you can just use PDF files without knowing anything about…

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PDF to image quality

The PDF file format was designed as much as possible to be Vector graphics. The problem with bitmaps and pixels is that pixels can only be on or off. While you can use some clever tricks such as anti-aliasing and hinting to smooth lines, you can’t draw fractions of a pixel. If a line is…

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PDF text co-ordinates

There are several ways to define PDF text co-ordinates with PDF. When you see the text onscreen, you can see the actual character. The outline of this is known as the ‘visible text box’ – if you draw it onscreen it would just touch the edges of the character. When a font is designed, most…

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What is PDF pagesize?

Page size can cause some confusion with PDFs because there are several possible values. All PDF files have a MediaBox which defines the size of the PDF in units. Values 0,0,595,842 (listed in the file as an Array [0 0 595 842]) are the normal values for an A4 portrait page, although they can also…

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