[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[bug #66132] [gropdf] develop a test for new gropdf image formats
From: |
G. Branden Robinson |
Subject: |
[bug #66132] [gropdf] develop a test for new gropdf image formats |
Date: |
Thu, 29 Aug 2024 00:12:06 -0400 (EDT) |
Follow-up Comment #2, bug #66132 (group groff):
Deri noted in bug #66114:
> This may be one of those problems for which there may not be a 100%
solution, and its a question of whether a less than 100% solution is worth it.
You may want to look at the program pdfdiff. If we had a "gold standard" pdf
of what the page should look like, it could be diffed by make test against the
new version.
> When I have investigated this before I found problems, many minute pixel
differences were shown when comparing text in the same document produced with
the same version of groff run on different systems. I put this down to
different ghostscript versions or different urw-font versions, since the -Z
output on both systems was identical. It would be possible to use it for
detecting missing images from a document, there would be whole missing squares
of pixels where the image should be!!
> It may also help to use a reduced dpi for ghostscript to use when converting
the pdfs to a bit map format, then very minor differences in the text may not
register. It may even be possible to roll our own pdfdiff using the pnm/pam
utilities.
_______________________________________________________
Reply to this item at:
<https://savannah.gnu.org/bugs/?66132>
_______________________________________________
Message sent via Savannah
https://savannah.gnu.org/
signature.asc
Description: PGP signature