[Bf-committers] Non-Standard sRGB OETF transform T51216

[Troy Sobotka]

On Mon, Apr 17, 2017, 11:09 AM Sergey Sharybin <sergey.vfx at gmail.com> wrote:

>
> Guess you're talking about issue reported in [1]. The root of the issue
> there is coming from OCIO itself, which has numerical stability issue
> in lookupLinear_1D (and it's SSE variant) when index is far above the
> possible LUT index.
>

I think the inverse lookup is going to be subject to quite a bit of
numerical degrading. You would need a shaper likely to properly resolve the
values.

Does the performance suffer with a 4096 LUT on the inverse Sergs? The 65k
LUT, in addition to having unnecessary / unused ranges for the older SPI
pipeline, is on the gargantuan side.

With respect,
TJS

>