Re: [css-gcpm][css-color] device-cmyk() interaction with RGB-space colors.

Hello Tab,

Tuesday, September 24, 2013, 11:06:30 PM, you wrote:

> On Tue, Sep 24, 2013 at 2:02 PM, Rik Cabanier <cabanier@gmail.com> wrote:
>>> As such, CMYK colors must be converted to an equivalent RGB color
>>
>> I think you meant to reverse that . RGB colors are converted to CMYK during
>> the printing process.

> No, I meant what I wrote.  We *must* have RGB colors in memory, so we
> can do compositing/blending/etc.  Those are only defined over RGB
> colors.

Clarification - RGB or XYZ or Lab colours (and thus, calibrated CMYK also, as the
profile gives a conversion to either XYZ or Lab).

Its not defined (or, a definition gives unexpected results) when used
directly on CMYK data. And device CMYK has no profile, so all you have
is the CMYK values.

>> IMO, I think this is something that should be done by the print processor
>> and not the browser since it most likely will not have the correct
>> information to make this decision.

> Yeah, but we can't actually preserve the color in CMYK.

Preserving the CMYK values is the entire point of device CMYK.




-- 
Best regards,
 Chris                            mailto:chris@w3.org

Received on Wednesday, 25 September 2013 11:06:39 UTC