Re: A solution for gamma-adjustment support in Wayland

Hi Chris, let me give a more considered reply: The conventional wisdom using video LUTs for calibration came about with CRTs. Pretty much all of that has to be thrown out with LCD's - they have a natural TRC that's nothing like a CRT, what the manufacturers have done is glue in hard wired tr

Re: A solution for gamma-adjustment support in Wayland

Chris Murphy wrote: > On Mon, Dec 26, 2016 at 10:25 PM, Graeme Gill I'm not sure what you are thinking of here - the existing per channel > VideoLUT API's are universally simple, and the only temptation in > making changes to this might be in the direction of better coordinating >

Re: A solution for gamma-adjustment support in Wayland

Chris Murphy wrote: Hi Chris, > As for CIEXYZ, to literally convert pixels into this space, or even as an > exchange space, > it will require minimum 16 bits per channel or there will be noticeable > quantization. It's > a huge color space. You could maybe get away with 8 bit per channel CIE >

Re: A solution for gamma-adjustment support in Wayland

Mattias Andrée wrote: Hi, > Ideally I think the display server should support sRGB, > CIE XYZ, and the monitors' native RGB for input. sRGB is > useful for programs such as image viewers and video players. Hmm. It's not a typical approach for a color managed workflow to have hard wired colorspac

Re: A solution for gamma-adjustment support in Wayland

Hi Graeme, On 27 December 2016 at 05:25, Graeme Gill wrote: > Daniel Stone wrote: >> 'The size and depth' and 'the CLUT' are no longer applicable. Colour >> management units, incorporating two LUTs and a matrix (coarsely, >> degamma-transform-regamma) are becoming rather common now. These units >

Re: A solution for gamma-adjustment support in Wayland

On Tue, Dec 27, 2016 at 11:35 AM, Mattias Andrée wrote: > > > get away with 8 bit per channel CIE L*a*b* but even > > that's questionable these days. > > I would reject CIE L*a*b* because it requires more > expensive conversion and more than two conversion > steps. > The conversion is lookup and

Re: A solution for gamma-adjustment support in Wayland

On Mon, Dec 26, 2016 at 10:25 PM, Graeme Gill wrote: > > Hi, > > Daniel Stone wrote: > > 'The size and depth' and 'the CLUT' are no longer applicable. Colour > > management units, incorporating two LUTs and a matrix (coarsely, > > degamma-transform-regamma) are becoming rather common now. These u

Re: A solution for gamma-adjustment support in Wayland

On Tue, 27 Dec 2016 11:23:34 -0700 Chris Murphy wrote: > On Mon, Dec 26, 2016 at 11:00 PM, Mattias Andrée > wrote: > > > On Tue, 27 Dec 2016 16:25:20 +1100 > > Graeme Gill wrote: > > > > > Hi, > > > > > > Daniel Stone wrote: > > > > 'The size and depth' and 'the CLUT' are no longer > > > >

Re: A solution for gamma-adjustment support in Wayland

On Mon, Dec 26, 2016 at 11:00 PM, Mattias Andrée wrote: > On Tue, 27 Dec 2016 16:25:20 +1100 > Graeme Gill wrote: > > > Hi, > > > > Daniel Stone wrote: > > > 'The size and depth' and 'the CLUT' are no longer > > > applicable. Colour management units, incorporating two > > > LUTs and a matrix (co

Re: A solution for gamma-adjustment support in Wayland

Daniel Stone wrote: > On 21 December 2016 at 11:31, Mattias Andrée wrote: >> This is not >> a sustainable solution, an API is necessary. It's bad >> enough that colour management is done by the compositor. > > I also cannot disagree more with your assertion that 'it's bad enough > that colour ma

Re: A solution for gamma-adjustment support in Wayland

On Tue, 27 Dec 2016 16:25:20 +1100 Graeme Gill wrote: > Hi, > > Daniel Stone wrote: > > 'The size and depth' and 'the CLUT' are no longer > > applicable. Colour management units, incorporating two > > LUTs and a matrix (coarsely, degamma-transform-regamma) > > are becoming rather common now. The

Re: A solution for gamma-adjustment support in Wayland

Hi, Daniel Stone wrote: > 'The size and depth' and 'the CLUT' are no longer applicable. Colour > management units, incorporating two LUTs and a matrix (coarsely, > degamma-transform-regamma) are becoming rather common now. These units > can be present per-plane as well as per-output/pipe. Sometim

Re: A solution for gamma-adjustment support in Wayland

On Wed, Dec 21, 2016 at 4:57 AM, Daniel Stone wrote: > I also cannot disagree more with your assertion that 'it's bad enough > that colour management is done by the compositor'. The compositor is > the very thing between clients producing pixels, and the final output. > If a compositor is unaware

Re: A solution for gamma-adjustment support in Wayland

On Wed, 21 Dec 2016 21:05:13 +0100 Kai-Uwe wrote: > Hello Mattias, > > Am 21.12.2016 um 12:31 schrieb Mattias Andrée: > > If there is no API for these thinks, functionality > > such as inverting the colours, lowering the temperature, > > and (requires matrices) simulating defective colour > > vi

Re: A solution for gamma-adjustment support in Wayland

Hello Mattias, Am 21.12.2016 um 12:31 schrieb Mattias Andrée: > If there is no API for these thinks, functionality > such as inverting the colours, lowering the temperature, > and (requires matrices) simulating defective colour > vision must be done in the compositor. This is not > a sustainable s

Re: A solution for gamma-adjustment support in Wayland

Hi Mattias, On 21 December 2016 at 11:31, Mattias Andrée wrote: > On Wed, 21 Dec 2016 10:40:44 + Daniel Stone wrote: >> The point is that I'm extremely wary of copying X11 by >> way of encoding this into an API; it's a truly dizzying >> space to even enumerate, let alone abstract. > > I thin

Re: A solution for gamma-adjustment support in Wayland

On Wed, 21 Dec 2016 10:40:44 + Daniel Stone wrote: > Hi Mattias, > > On 14 December 2016 at 00:20, Mattias Andrée > wrote: > > There should also be a protocol for identifying > > whether a VDC have CLUT that can be edited, and whether > > the compositor supports cooperative gamma. The s

Re: A solution for gamma-adjustment support in Wayland

Hi Mattias, On 14 December 2016 at 00:20, Mattias Andrée wrote: > There should also be a protocol for identifying whether a VDC have > CLUT that can be edited, and whether the compositor supports cooperative > gamma. The size and the depth of the CLUT should should also be > retrievable. Sinc

A solution for gamma-adjustment support in Wayland

The following text is also available in PDF format at . Please CC me, I am not subscribed to the mailing-list. ### Abstract ### With the advent of Wayland, our display server has lost a functionality — access to the graphic cards’ colo