Make white text visible


#1

I have a pdf that has some white text printed on it (so that it wouldn’t show up when the pdf gets printed by our print house)
Now I want to make it visible somehow so I can verify the text.
I have played around with the FixedPageUI settings, but the white text remains unvisible. Still it is there because when I do a search for a word that should be in the white text it is actually found. It gets marked in the SelectionColor, but the white text apparently also gets that same color, keeping it still invisible.
I’m not sure, but I think I got this working a long time ago in a much earlier version of SumatraPDF.
How can I get this white text to show up?
Thanks for any tips.


#2

@Roebie
There are limits to how much you can vary colour range via settings however
Have You tried

FixedPageUI [
TextColor = #ffffff
BackgroundColor = #777777

There was a change recently in the way colours are handled so you could try the older command line settings either

-set-color-range #dddddd #333333
or
-invert-colors

failing that try an older version say 2.0 from https://www.sumatrapdfreader.org/download-prev.html

-please let us know what worked for you


#3

@Roebie
whilst answering a line thickness issue on github, I was reminded of
15.2 Blackening Text, Lines and Fills from https://www.coherentpdf.com/cpdfmanual.pdf
this is a commercial program with a free not for commercial use version see http://community.coherentpdf.com/


#4

Instead of fiddling around with the color settings of your PDF viewer (Sumatra), why not simply edit the color of that bit of text with a PDF editor? Even a free editor such as PDF-XChange should hopefully be able to carry out such a minor edit.


#5

Peter
you are correct that the simplest way is to modify or remove pseudo redaction using an editor
and although I suggested a 3rd party product it was as a fall back,

the OP challenge was how can SumatraPDF be used to verify the text content, and my latest suggestion would be simply to select all the page to clipboard and paste the text as text in notepad


#6

@GitHubRulesOK
I have tried those and dozens others. Without the required effect.
-set-color-range and invert-colors don’t seem to do anything so I assume they’re not supported anymore.
If I understand coherentpdf correctly it’s a commandline tool to print pdf’s and make changes to them while doing so. This is absolutely overkill.

@SumatraPeter
The entire point is not to edit the pdf. These pdf’s are generated automatically by a VDP program (variable data publishing). They contain invoices, credit notes, reminders, commercial letters, … Then they are distributed to several print house where they are printed, put in boxes (together with books,…) or envelopes (e.g. in case of reminders) and put in the mail. The white text I’m talking about are data that should never get printed, but is useful to (e.g.) link a given pdf to a given customer, generation date, etc.
But to do that I need an out of the box way to make the white text visible, not by editing pdf’s. Remember, where talking several hundred pdf’s per week, totalling like 20,000 pages. Even for spot checks that is too much to go down the “edit the pdf” road.

Chosen solution…
I have tried three pdf viewers:
SumatraPDF with FixedPageUI [TextColor = #000000 BackgroundColor = #cccccc]
Foxit Reader with Preferences > Accessibility > Replace document colors > Custom color page background #CCCCCC and document text #000000 and “Only change the color of black text”.
Adobe Reader with exactly the same settings as Foxit Reader.

Just like SumatraPDF used to do in the past, Foxit Reader does exactly what I need: it shows the white text against a light grey background (CCCCCC)
Weirdly enough Adobe Reader does not, although the settings are exactly the same.
Here’s a screenshot of the three programs with the upper left corner of the pdf (where the white text is) visible. And yes, it’s the same document.
Foxit-AdobeReader-SumatraPDF

So I will need to use Foxit for these checks, even though I really don’t like the rest of the interface (esp. not the ribbon).

Thanks for all your suggestions and hopefully this feature is re-introduced in SumatraPDF someday.


#7

@Roebie
thanks for your feedback, It may still be possible to find a SumatraPDF solution, if we can test an example file,
can you produce one that behaves the same way but without any sensitive data ? and provide a dropbox or similar link to it?


#8

I’ll try to do that.
However this is my last day before my holiday leave, so I have a whole lot of other stuff to do first.
When I get back in two weeks I will try to produce an example file.