Hi, > I used the current programs jpegicc.exe and tifficc.exe (win2K) to convert two > images in jpg and tiff-format with a lot of RGB-patches into CMYK. Both have an > ColormatchRGB-profile embedded. The jpeg is created in Photoshop 7.0. > The command-line is : > > c:> tifficc -t0 -ocmykprinter.icm rgb.tif cmyk.tif > c:> jpegicc -t0 -ocmykprinter.icm rgb.jpg cmyk.jpg > > The result of the tiff-conversion is similar to the conversion Photoshop 7.0 > does (within delta-E=2). OK! > The result of the jpeg-conversion is awful. It looks like everything is > reverse. White is black, green is red, blue is yellow. > > What did I do wrong?
Nothing. This is a problem in the way Photoshop does store CMYK JPEG. I was told this comes from a mistake by a junior programmer in early versions of Photoshop. For compatibility sake Adobe has kept this particular encoding! There is workaround, however. You can find the patched files for jpeglib at http://www.littlecms.com/newutils.htm#jpegicc http://www.littlecms.com/jccolor.c http://www.littlecms.com/jdcolor.c The precompiled windows exe is already using these ones http://www.littlecms.com/jpegicc.exe Hope this helps Martí Maria The little cms project http://www.littlecms.com [EMAIL PROTECTED] ----- Original Message ----- From: "Goossen Rijnders" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Friday, September 27, 2002 5:43 PM Subject: jpegicc-problem > Hi, > > I used the current programs jpegicc.exe and tifficc.exe (win2K) to convert two > images in jpg and tiff-format with a lot of RGB-patches into CMYK. Both have an > ColormatchRGB-profile embedded. The jpeg is created in Photoshop 7.0. > The command-line is : > > c:> tifficc -t0 -ocmykprinter.icm rgb.tif cmyk.tif > c:> jpegicc -t0 -ocmykprinter.icm rgb.jpg cmyk.jpg > > The result of the tiff-conversion is similar to the conversion Photoshop 7.0 > does (within delta-E=2). OK! > The result of the jpeg-conversion is awful. It looks like everything is > reverse. White is black, green is red, blue is yellow. > > What did I do wrong? > Please help. The results of the tiff-conversion are that good! I would like to > see the same with pjg-images. > > Kind regards, > > Goossen Rijnders > > ------------------------------------------------------- This sf.net email is sponsored by:ThinkGeek Welcome to geek heaven. http://thinkgeek.com/sf _______________________________________________ Lcms-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/lcms-user
