Re: [Lcms-user] Out of gamut treatment (linear double precision sRGB -> 8-bit sRGB)

[Kai-Uwe B. <ku...@gm...>]

Wenzel Jakob <we...@cs...> schrieb:
>As you already hinted, this still does not work -- the value gets 
>clipped before ever reaching the profile. Is there a way to avoid this,
>
>or am I asking for something unreasonable?

I am not sure if a floating point 'mpet' profile can scale out of gamut input.

A more traditional and powerful way is to do tonemapping on the HDR data outside the CMM. That would be kind if intelligent stage befor sending to the dump ICC engine.

>On 09/07/2012 05:09 PM, Marti Maria wrote:
>> If you define a colorspace that has transfer functions of gamma 1.0,
>> primaries Rec709 and D65 as
>> white point you cannot call it "sRGB", just because this is not sRGB
>> but something close but not
>> sRGB.

>> BTW, obviously you cannot use the same sRGB as the input, that would
>> make impossible to
>> encode out of gamut colors, and doing (0.5, 0.5, 1000) clips the
>value
>> on the input - it
>> doesn't even reach the profile.

The sRGB curve is only defined inside the default range of 0.0->1.0. So you need a profile with an appropriate gamma description on input. Linear gamma of1.0 is the most easy way.

kind regards
Kai-Uwe