What do you mean by "without opening the pdf"? You will need to use the open function to read the file. If you don't want to "open a window for the user", that's likely possible.

A cursory glance through PDF::API2 doesn't tell anything, so maybe you'll have to inspect all page objects and check whether they are an image ("likely" colored) or using a non-grayscale color.

In reply to Re: Count Colour Pages in PDF by Corion
in thread Count Colour Pages in PDF by sureshrps

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