How to check PDF pages for resolution (DPI) of embedded images?

Question

Is there any free library, that can be used to get resolution of images in DPI contained by PDF file?

I\'ve tried the following code, using PDFSharp but the DPI it r

Answer 1

PDF's do not necessarily use DPI in their definitions. PDF's allow the document creator to define their own user coordinate space which may or may not map to anything similar to Dots Per Inch.

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