here are some examples of NAN like fillers. Turns the NAN black and then fills it by using the neighboring pixels.
set cut_paste_input [stack 0]
version 5.2200
push $cut_paste_input
Shuffle {
alpha black
name Shuffle4
selected true
xpos 910
ypos -178
}
set N34557040 [stack 0]
Expression {
expr0 r
expr1 g
expr2 b
expr3 (isnan(r)||isnan(g)||isnan(b))?1:0
name Expression14
label "NAN to Zero\n\n"
selected true
xpos 839
ypos -78
}
Expression {
expr0 isnan(r)==true?r(x+1,y-1):r
expr1 isnan(g)==true?g(x+1,y-1):g
expr2 isnan(b)==true?b(x+1,y-1):b
name Expression7
label "fill NaN"
selected true
xpos 839
ypos -40
}
Expression {
expr0 isnan(r)==true?r(x-1,y+1):r
expr1 isnan(g)==true?g(x-1,y+1):g
expr2 isnan(b)==true?b(x-1,y+1):b
name Expression8
label "fill NaN"
selected true
xpos 839
ypos -2
}
Expression {
expr0 "r == inf ? 0 : r"
expr1 "g == inf ? 0 : g"
expr2 "b == inf ? 0 : b"
name Expression15
label "NAN to Zero\n\n"
selected true
xpos 839
ypos 42
}
Blur {
channels alpha
size 1.5
name Blur4
selected true
xpos 839
ypos 80
}
Blur {
channels rgb
size 2
maskChannelInput rgba.alpha
name Blur5
selected true
xpos 839
ypos 118
}
push $N34557040
Expression {
expr0 r
expr1 g
expr2 b
expr3 (isnan(r)||isnan(g)||isnan(b))?1:0
name Expression11
label "NAN to Zero\n\n"
selected true
xpos 1010
ypos -112
}
Expression {
expr0 "r == inf ? 0 : r"
expr1 "g == inf ? 0 : g"
expr2 "b == inf ? 0 : b"
name Expression13
label "NAN to Zero\n\n"
selected true
xpos 1010
ypos -74
}
Erode {
channels rgb
size -0.75
maskChannelInput rgba.alpha
name Erode1
selected true
xpos 1010
ypos -30
}
Blur {
channels alpha
size 1.5
name Blur6
selected true
xpos 1010
ypos 8
}
Blur {
channels rgb
size 2
maskChannelInput rgba.alpha
name Blur7
selected true
xpos 1010
ypos 48
}
FilterErode {
channels rgb
size -1
filter triangle
maskChannelInput rgba.alpha
name FilterErode1
selected true
xpos 1010
ypos 86
}
Blur {
channels rgb
size 2
maskChannelInput rgba.alpha
name Blur8
selected true
xpos 1010
ypos 124
}
FilterErode {
channels rgb
size -1
filter triangle
maskChannelInput rgba.alpha
name FilterErode5
selected true
xpos 1010
ypos 162
}