On 4 Jul 2008, at 5:35 PM, Robin wrote: > On Fri, Jul 4, 2008 at 3:47 PM, Robin <[EMAIL PROTECTED]> wrote: >> Hi, >> >> I have some figures prouced from Matlab using imagesc command. An >> example is here: >> http://acrids.robince.net/robince/simA_theta1.pdf >> >> This should be rectangular grayscale blocks. It shows up correctly in >> acrobat. However in Preview and Skim the image is very blurred - the >> boundaries between the rectangular regions are no longer clear. >> Preview is much worse than skim (completely smoothed image) - with >> Skim you can make out some of the structure but it is blurred. >>
Really weird Skim and Preview give different results, as there is no setting in PDFKit other than the ones exposed in the preferences (in particular, whether it should anti-alias). So Preview must make some internal overrides to PDFKit to interpolate even more (though the only way I could think of makes absolutely no difference). It seems Skim is much closer to Adobe Reader (at least, Adobe Reader 9) >> A more knowledgable friend informs me: >> >>> Seems matlab tries exporting the centres of imagesc graphs as a >>> teeny >>> tiny bitmapped graphic which then scaled up. This is pretty much the >>> definition of a pathological case of bitmap scaling for any >>> algorithm >>> - with more pathology the smarter the algorithm - and betrays >>> imagesc's origins as part of the bitmap manipulation toolchain. >> >> Since there is a considerable difference between Preview and Skim I >> was wondering if there might be a hidden option for pdfkit somewhere >> that could cause either Preview or Skim to display the image properly >> - or whether anything else might be done to get either application to >> show imagesc plots correctly? > > > Some updated information from my friend: > >> hmmn, looks like os x ignores the "Interpolate" dictionary entry for >> postscript images. I've tried explicitly setting it to "false", the >> default, by hacking up a file exported from matlab and it merrily >> ignores it. My postscript fu is weak these days, so I may be wrong. >> >> As pretty much nothing sets this flag, ignoring it is almost >> certainly >> the right thing to do to make all pdf and ps files look beautiful... >> except when it isn't. From reading the red book the reason for the >> interpolation flag was to be able to explicitly turn /on/ >> interpolation in newer devices that supported it as it is pretty >> brutal computationally (by 1990s standards) and would hammer old >> hardware like printers. The specs sort of imply that in an ideal >> world >> interpolation would always be used, so MATLAB's dependence on its >> absence is pretty bogus. > > So I guess the question is - is it possible to make Skim respect the > 'Interpolate' setting? > > Cheers > > Robin No. Rendering the PDF is entirely up to PDFKit. Christiaan ------------------------------------------------------------------------- Sponsored by: SourceForge.net Community Choice Awards: VOTE NOW! Studies have shown that voting for your favorite open source project, along with a healthy diet, reduces your potential for chronic lameness and boredom. Vote Now at http://www.sourceforge.net/community/cca08 _______________________________________________ Skim-app-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/skim-app-users
