[Openicc] review of new wide gamut editing space

[Chris Murphy]

On Mar 21, 2012, at 10:42 AM, Kai-Uwe Behrmann wrote:

> 
> [ProPhoto] specifies unfortunately a gamma of 1.8, which is not good for 2.2/sRGB style display systems.

A totally specious claim, and that's quite diplomatic because it is hardly even plausible superficially. Kodak did quite a bit of research on the question of invertibility, the burden is on those who claim otherwise to demonstrate a deficiency.

On Mar 21, 2012, at 11:05 AM, Kai-Uwe Behrmann wrote:

> We need as well a intermediate space for handing off 8-bit data.

Two things, I agree with Jan-Peter that working with wide gamut images almost certainly necessitates 16bpc bitdepth. However, ROMM RGB as defined by Kodak came in 8bpc and 16bpc variants. So I don't understand the issue here.

Second, with 8bpc of data, all the more reason a TRC defined by a gamma 1.8 function is more appropriate. Again it's a space that you must convert *INTO* not just from.

As for the licensing, I'm not a lawyer, but this amounts to algorithms and while copyrightable, they're not patentable. So you can write your own with the identical algorithm under a new license.

Chris Murphy