Are you sure Preview is using the monitor profile? I thought Apple uses the Generic RGB profile when no profile is supplied - but I'm not sure. The profile is at /System/Library/ColorSync/Profiles/Generic RGB Profile.icc
The guys at the ColorSync mailing list might be able to answer this better... Mark On 08.06.2010, at 20:29, Kevin Gale wrote: > Hi. > > I'm looking for some advice / thoughts on how to composite images with and > without profiles. > > Some background.... > > Users can select and manipulate their digital camera pictures in our app > on-screen before they are composited into a single file with a sRGB profile > attached. Currently, our app does the following: > 1. If the image has a profile the data is transformed to sRGB when outputting > to file and to the monitor's profile for on-screen display. > > 2. If the image does not have a profile it assumes the data is already sRGB. > This means that when outputting to file no transformation is performed but > on-screen a generic sRGB profile is used as the input profile to transform to > the monitor's profile. > > > I have recently been revisiting this as I cannot decide if I am doing the > right thing here when dealing with images that do not have a profile. For > example, if I open an unprofiled image in Photoshop it assigns the sRGB > profile (same result as our app) while on the other hand if I open the same > image in Mac OS X Preview it appears to use the monitor's profile. I could > either keep things the way they are or instead grab the monitor's profile to > use as the input profile so that part of the composited image looks like the > original image opened in Mac OS X Preview. > > Hope this makes sense so far.... > > My thoughts are that neither of these is really right or wrong since the > image does not have any profile and the pixels are technically meaningless > (the data could, after all, be sRGB). The end-users of our app will have no > knowledge of profiles so to start prompting them with questions would cause > lots of headaches. However, there is always the situation where I have to > explain why the composited output from our app looks different to the > original pictures due to the app that the original pictures were viewed in. > > > Would anybody like to share their thoughts / advice on this? > > > Regards, > Kevin. > > E-MAIL DISCLAIMER > The information in this email is confidential and may be legally privileged. > It is intended solely for the addressee. Access to this email by anyone else > is unauthorised. If you are not the intended recipient, any disclosure, > copying, distribution or any action taken or omitted to be taken in reliance > on it, is prohibited and may be unlawful. All information provided, > including but not limited to, quotations, system specifications and > suggestions concerning hardware/software/services configurations are strictly > subject to our standard terms and conditions of business, copies of which are > available on request. > > ________________________________________________________________________ > This e-mail has been scanned for all viruses by Star. The > service is powered by MessageLabs. For more information on a proactive > anti-virus service working around the clock, around the globe, visit: > http://www.star.net.uk > ________________________________________________________________________ > > ------------------------------------------------------------------------------ > ThinkGeek and WIRED's GeekDad team up for the Ultimate > GeekDad Father's Day Giveaway. ONE MASSIVE PRIZE to the > lucky parental unit. See the prize list and enter to win: > http://p.sf.net/sfu/thinkgeek-promo > _______________________________________________ > Lcms-user mailing list > Lcms-user@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/lcms-user ------------------------------------------------------------------------------ ThinkGeek and WIRED's GeekDad team up for the Ultimate GeekDad Father's Day Giveaway. ONE MASSIVE PRIZE to the lucky parental unit. See the prize list and enter to win: http://p.sf.net/sfu/thinkgeek-promo _______________________________________________ Lcms-user mailing list Lcms-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/lcms-user
