On Fri, 2026-02-06 at 11:09 +0200, Pekka Paalanen wrote: > On Fri, 2 Jan 2026 13:40:21 -0500 > Harry Wentland <[email protected]> wrote: > > > On 2026-01-01 07:37, Shengyu Qu wrote: > > > > > > > > > 在 2025/12/30 02:53, Shengyu Qu 写道: > > > > > > > > > > > > 在 2025/12/24 3:44, NÃ colas F. R. A. Prado 写道: > > > > > > Given the lack of support for writeback connectors on the > > > > > MediaTek KMS driver, combined with limited hardware > > > > > documentation, I haven't been able to verify the correctness > > > > > of > > > > > each curve, only that they were visually sane (gamma curves > > > > > made > > > > > the image on the display brighter, while inverse gamma made > > > > > it > > > > > darker). > > > > > > > > Hmmm I don't think this is acceptable. sRGB/scRGB has two > > > > transfer > > > > functions mentioned in original specification[1]. To keep color > > > > accuracy, we need someone from mediatek confirm whether this is > > > > piece- wise or pure power 2.2 transfer function, this is > > > > already > > > > done in original amdgpu color pipeline series, sRGB means > > > > piece-wise while also dedicated power 2.2 function exists. > > > > Not sure what you mean with this not being acceptable. This is > > about > > enabling HW support for this functionality. Not every HW has > > writeback for testing. At some point you'll have to trust the > > driver > > devs if you're going to use functionality of the driver. We're not > > always going to get everything perfect, but if that's really such a > > worry you can always use shaders to do precisely what you want. > > > > Hi Harry, > > yes, but I understood that in this case, the hardware documentation > available is so vague that it's impossible to say what it will > actually > do. There are no formulas given or referenced in the documentation, > are > there, Nícolas?
No formulas at all, the only documentation I had available for the curves was the register definition, which simply lists the possible values: SCRGB, BT709, BT2020, HLG. -- Thanks, Nícolas
