A Dimarts, 14 de juliol de 2009, Hal V. Engel va escriure: > On Monday 13 July 2009 02:51:30 pm Albert Astals Cid wrote: > > Hal? > > > > Albert > > Albert, > > If you are asking if I think the last version of the white point correction > patch that I sent in is good then the answer is yes. It affects the output > and with the patch (using a good display profile) the results in the Altona > test PDF are correct (IE. both parts of the test areas match). The patch > is also to the PDF spec. as far as I can tell. I have also been using it > on my system for some time now without issues.
Can you please attach two images of the Altone test PDF with and without the patch, because really really really i don't see any difference with and without the patch. Albert > > Hal > > > A Dimarts, 23 de juny de 2009, Albert Astals Cid va escriure: > > > A Dissabte, 23 de maig de 2009, Hal V. Engel va escriure: > > > > On Saturday 23 May 2009 02:55:29 am Albert Astals Cid wrote: > > > > > > According to the PDF spec. the Y white point value should always > > > > > > be 1.0. So it might be possible to just do the correction to X > > > > > > and Z since this would make the code slightly more efficient. > > > > > > Also I now think it would be better to do this in > > > > > > GfxCalGrayColorSpace::getXYZ() and GfxLabColorSpace::setXYZ() > > > > > > instead of in the locations right after calls to these functions. > > > > > > > > > > When i mean no difference i mean "diff" says the files are exactly > > > > > the same, not that i'm not able to see a difference in them. > > > > > > > > > > May it be because i'm not using any color profile? > > > > > > > > > > Albert > > > > > > > > It could be but the current code base defaults to sRGB as the output > > > > profile if one is not specified by the calling app. So if poppler > > > > was built using USE_CMS then by default it should be using sRGB as > > > > the output color space for CIELab, Cal* and ICC objects. > > > > > > > > To confirm that you are using a profile you might consider modifying > > > > your code so that it explicitly sets the output profile by calling > > > > setOutputProfileName() or setOutputProfile() before opening the > > > > document. For additional testing I am attaching a profile intended > > > > for testing that causes the colors to be transformed in a way that is > > > > unmistakable because it transforms blues into reds and reds into > > > > blues. Using this profile it should be easy to confirm that your code > > > > is actually using an output profile and also which parts of the > > > > rendered output are using the output profile. > > > > > > > > No matter what output profile is being used there should be at least > > > > some difference in the resulting RGB values of CIELab and CalGray > > > > objects if the white point of the object is NOT X = Y = Z = 1.0. I > > > > have placed printf() statements in the code to confirm that this is > > > > altering the XYZ values of the CIELab objects in the altona pdf and > > > > it is. I have also confirmed through testing that this makes a > > > > visible difference in the rendered output at least if the white point > > > > is significantly different from X = Y =Z = 1.0. > > > > > > > > Also I cleaned up the white point code so that the white point > > > > correction is now taking place in the getXYZ() functions which is > > > > where is really belongs. I have attached a patch with this set of > > > > changes. > > > > > > Ok, i've tested the patch and yes, i need to load a displayProfile, > > > otherwise it seems to do nothing, the problem is that the differences i > > > see are so minor i can't say if it is correct with the patch or without > > > it. > > > > > > Do you have other PDF that shows a more visible difference? > > > > > > Koji is that inside your area of expertice and can say yay/nay to the > > > patch? > > > > > > Anyone else? > > > > > > Albert > > > > > > > Hal > > > > > > _______________________________________________ > > > poppler mailing list > > > [email protected] > > > http://lists.freedesktop.org/mailman/listinfo/poppler > > _______________________________________________ > poppler mailing list > [email protected] > http://lists.freedesktop.org/mailman/listinfo/poppler _______________________________________________ poppler mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/poppler
