[RGMOfficial]

Originally Posted by SaurusX

Another thing to consider regarding rainbows is that they generally live only on DIAGONAL edges. Would it be preferable to alter the mask to only affect diagonal edges? It would add another layer of realism to the effect.

Can you provide an example script?

Here's the mask script:

function dpc_uumidpass(
\   clip C, int "tlo", int "thi", bool "setupmode")
{
    tlo    = Default(tlo, 128)
    thi    = Default(thi, 148)
    setupmode = Default(setupmode, false)

    CG = C.Grayscale()
    Last = CG
    Blur(1, 1)
    FFT3DFilter(bt=1, bw=64, bh=64, ow=32, oh=32,
    \  sigma=0, sigma2=0, sigma3=500, sigma4=100000)
    Subtract(UUGaussianBlurY(rad=1))
    mt_expand()
    Grayscale()
    return (setupmode) 
    \ ? dpc_histostretch(50.0, 0.01, 1.8, true)
    \ : Levels(tlo, 1.8, thi, 0, 255, coring=false)
}

function UUGaussianBlurY(clip C, float "var", float "rad")
{
    var = Max(0.0, Float(Default(var, 1.0)))
    rad = Max(1.0, Float(Default(rad, Pow(var, 0.5))))
    var = Pow(Min(Max(0.0, rad), 60.0), 2.0)
    
    w0 = C.Width
    h0 = C.Height
    w1 = Round(w0/rad)
    h1 = Round(h0/rad) /* formerly "w0/rad" ?? */

    B = C.BilinearResize(
    \         Min(Max(12, w1 + (w1 % 2)), w0), 
    \         Min(Max(12, h1 + (h1 % 2)), h0))

    B = B.Blur(1.0).Blur(1.0)
    
    return (var<0.01) ? C 
    \    : (var<1.5)  ? C.Blur(0.85 * var)
    \    : (B.Width>8 && B.Height>8) ? B.GaussResize(w0, h0)
    \    : B.BilinearResize(w0, h0)
}

Also, sorry for the late reply.