How do I know if PDF pages are color or black-and-white?

Question

Given a set of PDF files among which some pages are color and the remaining are black & white, is there any program to find out among the given pages which are color and whi

Answer 1

ImageMagick has some built-in methods for image comparison.

http://www.imagemagick.org/Usage/compare/#type_general

There are some Perl APIs for ImageMagick, so maybe if you cleverly combine these with a PDF to Image converter you can find a way to do your black & white test.