Re: Sending VCGT data to wide gamut monitors using i2c?

[Graeme Gill <graeme2 argyllcms com>]

Richard Hughes wrote:
> Ideas and feedback welcome. If anyone has ever tried this before, I
> would appreciate any advice. Thanks.

Naturally I've considered this. The problems are:

	There is no standard X mechanisms for doing this. X accesses
the monitors i2c to load the EDID, but doesn't provide a general purpose
communication channel. The logical place for it is in XRandR, since it
knows about outputs (monitors). Although the i2c might be accessed elsewhere
in Linux, there is the problem of figuring out the association between
the i2c and the outputs.

The above wouldn't have stopped me doing this for MSWin and OS X,
but there is the second problem: there is no standard i2c video monitor
protocol for this. Each manufacturer can do it their own way, and
doesn't publish how they do it. You have to reverse engineer it
for each monitor. Without access to a representative set of
monitors, the coverage of monitors is likely to be spotty.
(I don't have a single monitor with this feature.)

Graeme Gill.