[cups] question about image size

[Pascal Obry]

My goal is to print a picture from the lp command line directly sent to
a CUPS queue. I don't want CUPS to resize my image, so I don't want to
use the the fit-to-page option.

$ lp -d <printer-queue> file.jpg

With 0 margin. So for the print area, how to compute the needed image
size to fit on a single page? The question can also be stated as:

How many pixels per inch can I fit on the page? I suppose that this is a
CUPS property which is rendering the page but I cannot find the answer.

My experience shows that 300 works, but is it true for every printer
used via CUPS?

Thanks,

-- 
  Pascal Obry /  Magny Les Hameaux (78)

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