this converts the luminance of the linear input signal to an srgb viridis colour map, like in the following example:
note that the output will be sRGB, so if you need rec2020, insert an instance
of colour
after this and set it to image
mode.
input
rec2020 values, the luminance will be visualisedoutput
the sRGB viridis coloured version of the inputexposure
the exposure correction value in stops