<br><br><div class="gmail_quote">On 1 November 2011 08:20, Stefan Löffler <span dir="ltr"><<a href="mailto:st.loeffler@gmail.com">st.loeffler@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
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Hi,<div class="im"><br>
<br>
On 2011-10-28 02:23, Paul A Norman wrote:<br>
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<div class="gmail_quote">
<div>Thanks Stefan sorry for the delay been very busy. Its used
when needing to check colour use in text,
graphs, graphics and illustrations for indication of the
result of grey-scale printing (sometimes inaccurately
called black and white printing) - invaluable to be able to
preview on screen without a printout. Means that any colours
that are too close when viewed in greyscale, can be colour
adjusted during editing.</div>
<div><br>
</div>
<div>Its already in the pdfview.exe (MUPDF a lightweight PDF and
XPS viewer)<span style="background-color:transparent"> project
(Atrifex Software Inc) </span><a href="http://www.mupdf.com/" style="background-color:transparent" target="_blank">http://www.mupdf.com/</a><span style="background-color:transparent"> </span><span style="background-color:transparent">and very effective
there. </span></div>
<div><span style="background-color:transparent">It is
activated in their viewer, like everything else they do, by
a keyboard key, c (information in info.txt - does not appear
in the Help About box)</span></div>
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Thanks for the info. Indeed, I used it (the info, and MuPDF) just
today to check if some figures work reasonably well in grayscale.<br>
<br>
I've also added this to the pdf viewer wishlist. The one concern I
have about this is that doing it right is far from trivial. As BPJ
suggested, the only "proper" way of doing this is to do proper color
management. This is far beyond the scope for now, so we'd have to
settle for some approximation (which MuPDF most likely does
internally, too). But I guess that should be doable.<br></div></blockquote><div><br></div><div>I am not sure that the complications/complexities of entering the world of proper colour management is worth the result, where I feel that all we are probably actually looking for is an indication of likely outcomes so that colours producing likely grey scale conflicts can be adjusted in editing?</div>
<div><br></div><div>In the still being developed TeXworks insert colour dialogue, I have a few simple algorithms begged, borrowed, adjusted (but not stolen), one of which renders RGB to grey-scale well enough for most purposes (I think I adjusted it to recommendations in Uwe Kern's Xcolor package documentation). </div>
<div><br></div><div>As the screens are nearly all effectively RGB something as simple as that may help on a Qt area draw routines perhaps? <a href="http://twscript.paulanorman.com/downloads/?InsertColour" style="background-color: transparent; ">http://twscript.paulanorman.com/downloads/?InsertColour</a></div>
<div><br></div><div>May be if deemed necessary, CMYK workflow could be detected in the document's xcolor or other package settings? But if someone is working towards CMYK output, then they are not seeing their colours on screen in the pdf properly any way? Or are there screens/graphic-drivers out there that have that degree of colour management?</div>
<div><br></div><div>Something is nagging the back of my mind that Qt has some sort of draw/paint routine <em style="background-color: rgb(255, 255, 255); font-style: normal; font-family: arial, sans-serif; line-height: 16px; ">convertToGrayScale</em></div>
<div><br></div><div>Paul</div><div><br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"><div bgcolor="#FFFFFF" text="#000000"><font color="#888888">
<br>
-Stefan<br>
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