Am 27.05.2011 15:09, schrieb Hartmut Henkel: >>> @luigi: an ICC profile definitely breaks the <png copy> rules >>> >>> The only chunks left are >>> >>> IHDR PNG image header: 5900x4094, 8bits/sample, truecolor, >> noninterlaced >>> IDAT PNG image data >>> .. >>> IDAT PNG image data >>> IEND end-of-image marker >>> >>> Mh, where is the show stopper? The compression method? >>> >> Looks like some of ConTeXt PDF/X-related settings is causing this. If I >> reduce the code to the pure picture, the '(PNG copy)' is triggered. >> Probably the active color management (default color space) is breaking >> the copy process here. > Sorry Hartmut, my last statement is complete BS. I made a 'blind' run in my lunch break, not inspecting the pdf. And sadly I had forgotten, that I changed the test file yesterday to use a small png test graphic instead of my big png. *brain vs. full stomach: 0:1*
So the PDF/X settings have no influence on this. The big png is not 'copied'. Anyhow, this is not a serious problem and honestly I don't have that much time now. When I have some more time I will use gdb to find the failing condition in writepng.w. Will be interesting, the last time I used gdb is more than 10 years ago. Thanks for all answers so far. Regards, Peter > must be some \pdfimageapplygamma > 0, only this and the \pdfimagehicolor > primitive can influence this low level stuff. > > Btw, just \pdfimageapplygamma > 0 (without setting \pdfgamma and > \pdfimagegamma) already changes the PNG image, since the luatex (and pdftex) > internal defaults are not gamma-neutral. No idea if (and then > to which value) this should be fixed. > > Regards, Hartmut ___________________________________________________________________________________ If your question is of interest to others as well, please add an entry to the Wiki! maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context webpage : http://www.pragma-ade.nl / http://tex.aanhet.net archive : http://foundry.supelec.fr/projects/contextrev/ wiki : http://contextgarden.net ___________________________________________________________________________________