[poppler] Question about setting PPI when generating image from pdftoppm

[Jason Crain]

On Fri, Jul 21, 2017 at 01:52:16PM -0700, Min Su wrote:
> I'm trying to set PPI when generating image from pdftoppm,but it seems like
> we only have parameters to set DPI "-r". I think the "r" here means
> resolution and the value should be a DPI. Since DPI is different from PPI,
> what if I want to set resolution by using PPI? Is there a way to translate
> them or there's another parameter which can take PPI?

Probably the manpage and --help text are inaccurate and should say PPI
instead of DPI, since pdftoppm is outputting to an image and not a
printer.