Hi, I think I may have found a solution to the problem of reading screen pixels and deducing what the actual sRGB value is when displayed by a colour aware program.
Could you tell me if I have got a reasonable plan, or if I still do not understand what is going on (more than likely!). Firstly I assume that if I take a picture in a camera, in say sRGB, then any colour aware program will render it on my screen with exactly the same screen values - true? Anyway what I thought was, that if I create a spectrum of all the colours horizontally in a image and then create a vertical luminosity blend - I should get a good presentation of most colours and tones. If I then saved this image, with an embedded sRGB profile, I could then read the sRGB values from the file using lcms (or Adobe CMM?) and compare them to the screen pixel values when the same image is displayed by photoshop (or any colour aware program?). I should then have a crude mapping between the two, in order to deduce the sRGB value from a screen value. Is this sensible, or am I completely off the mark? I realise that I would have to re-calibarate this mapping each time I re-calibrate the screen. Thank you Chris ----- Original Message ----- From: "Leonard Rosenthol" <[EMAIL PROTECTED]> To: "Louis Solomon [SteelBytes]" <[EMAIL PROTECTED]> Cc: <lcms-user@lists.sourceforge.net> Sent: Monday, February 04, 2008 4:01 PM Subject: Re: [Lcms-user] Colour management via screen sampling > On Feb 4, 2008, at 3:26 AM, Louis Solomon [SteelBytes] wrote: > > oh, and Photoshop does not work like any other program you are > > likely to > > meet. I believe it does it's own conversion using Adobe ACE > > instead of > > Windows ICM, and then copies that to video memory using a lower > > level API > > (DDI?). just a hunch - unproven. > > > While the details aren't 100% accurate, you are completely correct > that Photoshop (and other Adobe applications) have their own color > management and rendering system and so any screen pixel values you > retrieve can NOT be "inverted back" to the original source colors. > > Leonard Rosenthol > Adobe Systems > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Lcms-user mailing list > Lcms-user@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/lcms-user ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Lcms-user mailing list Lcms-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/lcms-user
