A Dissabte, 27 de juny de 2009, James Cloos va escriure: > >>>>> "Albert" == Albert Astals Cid <[email protected]> writes: > > Albert> Well i did it by empirical testing, get the pdf remove the > Albert> /Matte[0 0 0] entry of the object 51 and see how the left "More > Albert> Text Here TBD" in Adobe Acrobat is rendered with the exact same > Albert> color we get in poppler. > > My compile is a bit long in the tooth (about 60 days); there must have > been a relevant change in that time; I do not see a difference from > overwriting /Matte [0 0 0] with spaces.
What changes is what Adobe Acrobat renders, not what us render. Still don't understand why if c′ = m + α × (c − m) with m = 0 Albert > > Albert> Yep, looking at the formula for Matte color calculation it seems > Albert> that Matte 0 0 0 should not affect rendering at all, Leonard can > Albert> you shed some light here? > > >> The reply was, of course, supposed to go to bugz-d rather than the > >> list. But since it was wrong, I’m not going to correct that.... > > Albert> ¿¿?? > > I meant that I was trying to post a comment to the bug via that email; > the reply-to munging on the poppler-bugs list means that, to do that, > I have to manually edit the To: in the reply. With the last part I > meant that, since I can now see the difference the bug reported saw, > the first paragraph of my reply was incorrect and therefore there was > no point in re-sending the post to bugzilla..... > > >> So, to handle Matte, the ref says the SMask’s Width and Height have > >> to match the primary image’s, > > Albert> What the spec doesn’t say is what one should do if they are not > Albert> the same :-/ > > Indeed. The Right Thing To Do, given a pre-multiplied soft mask with > a different pixel-size than the image it applies to, is complicated at > best. (Except, of course, when the main image is an integer×integer > multiple of the mask’s size, where resizing the mask to match the main > image is trivial.) > > Incidently, for those reading along, c′ = m + α × (c − m) ımplies that > as α varies ∈ [0,1], c′ varies ∈ [m,c]. > > So dealing with non-conforming PDF files will be the only difficult part. > > >> Should OutputDev::drawSoftMaskedImage() get another arg to pass the > >> Matte array? Or should it be added to the GfxImageColorMap object? > > Albert> C++ way is having GfxSoftMaskImageColorMap subclassing > Albert> GfxImageColorMap that adds the Matte entry. > > Makes sense. As you might guess, I’ve mostly been hacking in C of late. > > -JimC _______________________________________________ poppler mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/poppler
