Hi there,
this is the first of a series of gizmos that I’m developing right now. This one is an enhanced Keyer gizmo that apart from having the usual Nuke’s keyer operations and options, it has some more keying operations and options that can help in keying process. In the following lines, I will explain in more detail these improvements and I will finish this post by sharing the code of the gizmo. However, if you prefer, you could download it from Nukepedia and start trying it. Please, I will really appreciate your feedback.
As you can see, the first additional option is ‘Enable Lin>Log preprocess’. This checkbox activates and deactivates a Lig2Log node that expands the mid tones range which can help (in some situations) to key a certain element better.
When selecting ‘Luminance Key’ operation, a checkbox and some sliders appear. The checkbox allows creating a custom luminance algorithm defining how much influence do R, G and B channels have in the luminance. The sum of the three amounts must be 1. I have tried to force the node to help users to achieve that result automatically, but as I’m a Python beginner user, the code is not perfect. Sometimes it can be possible to channel amounts to achieve negative values. Don’t worry, the error is usually really small and I have placed clamp nodes to prevent negative and over 1 values getting into the equation.
Chrominance operation lets you sample a color from the image. That color’s RGB values are mapped to 0,0,0 XYZ values and a matte image is generated calculating the distance in 3d space between the sampled values and the rest of the pixels.
As soon as you select Difference Key another input appears in the gizmo. You can connect your cleanplate to in or just a solid color and a matte of the difference between both of them will be created.
The last operation is Bump Keyer. It is useful to generate a matte of the bump details of the image. ‘Blur size’ is a kind of threshold to decide what should the keyer consider as bump detail. ‘Bum Subtraction’ helps to define better that detail. ‘Alternative Method’ sometimes can provide a better result.
Finally, you can clamp the output alpha using the ‘Clamp alpha’ checkbox.
I hope you find this gizmo useful. I would really appreciate if you could spend some minutes giving me feedback about it 🙂 As promised, here is the code:
set cut_paste_input [stack 0]
version 11.1 v2
push $cut_paste_input
Group {
name xa_Keyer1
knobChanged "\nn=nuke.thisNode()\nk=nuke.thisKnob()\nif k.name() == \"keyerOp\":\n keyerOperation = n\['keyerOp'].getValue()\n\n if keyerOperation == 6:\n n\['customLum'].setVisible(True)\n n\['rMult'].setVisible(True)\n n\['gMult'].setVisible(True)\n n\['bMult'].setVisible(True)\n n\['chroCol'].setVisible(False)\n n\['bumpBlur'].setVisible(False)\n n\['bumpSub'].setVisible(False)\n n\['bumpA'].setVisible(False)\n with n:\n nuke.delete(nuke.toNode('cleanplate'))\n\n elif keyerOperation == 10:\n n\['chroCol'].setVisible(True)\n n\['customLum'].setVisible(False)\n n\['rMult'].setVisible(False)\n n\['gMult'].setVisible(False)\n n\['bMult'].setVisible(False)\n n\['bumpBlur'].setVisible(False)\n n\['bumpSub'].setVisible(False)\n n\['bumpA'].setVisible(False)\n with n:\n nuke.delete(nuke.toNode('cleanplate')) \n\n elif keyerOperation == 11:\n n\['chroCol'].setVisible(False)\n n\['customLum'].setVisible(False)\n n\['rMult'].setVisible(False)\n n\['gMult'].setVisible(False)\n n\['bMult'].setVisible(False)\n n\['bumpBlur'].setVisible(False)\n n\['bumpSub'].setVisible(False)\n n\['bumpA'].setVisible(False)\n with n:\n iN = nuke.nodes.Input()\n iN\['xpos'].setValue(-1140)\n iN\['ypos'].setValue(221)\n iN.setName('cleanplate')\n nuke.toNode('Dot14').setInput(0, iN)\n\n elif keyerOperation == 12:\n n\['bumpBlur'].setVisible(True)\n n\['bumpSub'].setVisible(True)\n n\['bumpA'].setVisible(True)\n n\['chroCol'].setVisible(False)\n n\['customLum'].setVisible(False)\n n\['rMult'].setVisible(False)\n n\['gMult'].setVisible(False)\n n\['bMult'].setVisible(False)\n with n:\n nuke.delete(nuke.toNode('cleanplate'))\n\n else:\n n\['customLum'].setValue(False)\n n\['customLum'].setVisible(False)\n n\['rMult'].setVisible(False)\n n\['gMult'].setVisible(False)\n n\['bMult'].setVisible(False)\n n\['chroCol'].setVisible(False)\n n\['bumpBlur'].setVisible(False)\n n\['bumpSub'].setVisible(False)\n n\['bumpA'].setVisible(False)\n with n:\n nuke.delete(nuke.toNode('cleanplate'))\n\n if keyerOperation > 9:\n with n:\n cN = nuke.toNode('Keyer1')\n cN\['operation'].setValue(8)\n\n else:\n with n:\n cN = nuke.toNode('Keyer1')\n cN\['operation'].setValue(int(keyerOperation))\n\n\nelif k.name() == \"rMult\" or k.name() == \"gMult\" or k.name() == \"bMult\":\n rValue = n\['rMult'].getValue()\n gValue = n\['gMult'].getValue()\n bValue = n\['bMult'].getValue()\n lumValue = rValue+ gValue + bValue\n if lumValue != 1:\n if k.name() == 'rMult':\n n\['gMult'].setValue(n\['gMult'].getValue()-((lumValue-1)/2))\n n\['bMult'].setValue(n\['bMult'].getValue()-((lumValue-1)/2))\n gValue = n\['gMult'].getValue()\n bValue = n\['bMult'].getValue()\n if gValue < 0:\n n\['gMult'].setValue(0)\n n\['rMult'].setValue(n\['rMult'].getValue()-(abs(gValue)/2))\n n\['bMult'].setValue(n\['bMult'].getValue()-(abs(gValue)/2))\n if bValue < 0:\n n\['bMult'].setValue(0)\n n\['rMult'].setValue(n\['rMult'].getValue()-(abs(bValue)/2))\n n\['gMult'].setValue(n\['gMult'].getValue()-(abs(bValue)/2))\n elif k.name() == 'gMult':\n n\['rMult'].setValue(n\['rMult'].getValue()-((lumValue-1)/2))\n n\['bMult'].setValue(n\['bMult'].getValue()-((lumValue-1)/2))\n\n if rValue < 0:\n n\['rMult'].setValue(0)\n n\['gMult'].setValue(n\['gMult'].getValue()-(abs(rValue)/2))\n n\['bMult'].setValue(n\['bMult'].getValue()-(abs(rValue)/2))\n if bValue < 0:\n n\['bMult'].setValue(0)\n n\['rMult'].setValue(n\['rMult'].getValue()-(abs(bValue)/2))\n n\['gMult'].setValue(n\['gMult'].getValue()-(abs(bValue)/2))\n\n else:\n n\['rMult'].setValue(n\['rMult'].getValue()-((lumValue-1)/2))\n n\['gMult'].setValue(n\['gMult'].getValue()-((lumValue-1)/2))\n\n if gValue < 0:\n n\['gMult'].setValue(0)\n n\['rMult'].setValue(n\['rMult'].getValue()-(abs(gValue)/2))\n n\['bMult'].setValue(n\['bMult'].getValue()-(abs(gValue)/2))\n if rValue < 0:\n n\['rMult'].setValue(0)\n n\['rMult'].setValue(n\['rMult'].getValue()-(abs(rValue)/2))\n n\['gMult'].setValue(n\['gMult'].getValue()-(abs(rValue)/2))\n" tile_color 0xff00ff label "\[value keyerOp]" selected true xpos 67 ypos -110 addUserKnob {20 keyerTab l Keyer} addUserKnob {41 in l Input t "Which channels to calculate the key from" T Shuffle8.in} addUserKnob {6 lin2log l "Enable Lin>Log preprocess" t "Converts the input from linear to log giving more space to mid tones in order to improve the chances of keying specific areas" +STARTLINE}
addUserKnob {4 keyerOp l Operation t "red, green, blue = use that channel\nscreen = subtract that channel from others\nluminance = use CIE luminance value\nsaturation = use color saturation\nmax, min = max or min of red,green,blue\nchrominance = sets picked color in the origin of 3d space and calculates the distance from ofther pixels to it\ndifference = compares the input with the cleanplate\nbump = generates a matte for bump details" M {"Red Keyer" "Green Keyer" "Blue Keyer" Redscreen Greenscreen Bluescreen "Luminance Key" "Saturation Key" "Max Keyer" "Min Keyer" "Chrominance Key" "Difference Key" "Bump Keyer" "" "" "" "" ""}}
keyerOp "Luminance Key"
addUserKnob {6 customLum l "Enable Custom Luminance" t "Enables the possibility to generate a custom luminance deciding how much influence R, G and B channels are going to have on it. The sum of R, G and B must be equal to 1. " +STARTLINE}
addUserKnob {7 rMult l "Red Amount"}
rMult 0.3
addUserKnob {7 gMult l "Green Amount"}
gMult 0.59
addUserKnob {7 bMult l "Blue Amount"}
bMult 0.11
addUserKnob {18 chroCol l color t "Set this value as origin to calculate the distance between other pixel values" +HIDDEN}
chroCol {0 0 0}
addUserKnob {6 chroCol_panelDropped l "panel dropped state" -STARTLINE +HIDDEN}
addUserKnob {6 chroCol_panelDropped_1 l "panel dropped state" -STARTLINE +HIDDEN}
addUserKnob {6 chroCol_panelDropped_1_1 l "panel dropped state" -STARTLINE +HIDDEN}
addUserKnob {6 chroCol_panelDropped_1_1_1 l "panel dropped state" -STARTLINE +HIDDEN}
addUserKnob {6 chroCol_panelDropped_1_1_1_1 l "panel dropped state" -STARTLINE +HIDDEN}
addUserKnob {7 bumpBlur l "Blur Size" t "Modify this value to decide what should be consider as bump. To pick tiny details, use a low value." +HIDDEN R 0 100}
bumpBlur 14.5
addUserKnob {7 bumpSub l "Bump Subtraction" t "Helps to filter details" +HIDDEN R 0 0.5}
bumpSub 0.05
addUserKnob {6 bumpA l "Alternative Method" t "Sometimes it helps to improve the chances of succesful keying" +HIDDEN +STARTLINE}
addUserKnob {26 ""}
addUserKnob {41 keyerRange l Threshold t "Specify the trapezoid used to key. Goes linearly from (A,0) to (B,1), and then from (C,1) to (D,0). If C and D are the same it will map everything >C to 1." T Keyer1.range}
addUserKnob {6 clamp l "Clamp Alpha" t "Clamp the output alpha to keep values between 0 and 1" +STARTLINE}
clamp true
addUserKnob {26 ""}
addUserKnob {26 about l "" +STARTLINE T "Developed by Xabier Arrieta.\nhttps://arrieta.me"}
}
BackdropNode {
inputs 0
name BackdropNode1
tile_color 0xbababa01
label "<center>Custom Luminance"
note_font_size 50
xpos -292
ypos -5
bdwidth 454
bdheight 485
}
BackdropNode {
inputs 0
name BackdropNode2
tile_color 0xbababa01
label <center>Keyer
note_font_size 50
xpos 209
ypos 874
bdwidth 243
bdheight 197
}
BackdropNode {
inputs 0
name BackdropNode3
tile_color 0xbababa01
label "<center>Recover Original RGB"
note_font_size 50
xpos 188
ypos 1927
bdwidth 284
bdheight 274
}
BackdropNode {
inputs 0
name BackdropNode4
tile_color 0xbababa01
label "<center>Chrominance Key"
note_font_size 50
xpos -724
ypos -11
bdwidth 357
bdheight 366
}
BackdropNode {
inputs 0
name BackdropNode5
tile_color 0xbababa01
label "<center>Difference Key"
note_font_size 50
xpos -1206
ypos -15
bdwidth 441
bdheight 624
}
BackdropNode {
inputs 0
name BackdropNode6
tile_color 0xbababa01
label "<center>Bump Keyer"
note_font_size 50
xpos -504
ypos 1060
bdwidth 572
bdheight 740
}
Input {
inputs 0
name input
xpos 290
ypos -274
}
Shuffle {
name Shuffle8
label "\[string toupper \[value in]]\[if \{\[value out]==\"rgba\"\} \{return\} else \{return \" to \"\}]\[if \{\[value out]==\"rgba\"\} \{return\} else \{return \[string toupper \[value out]]\}]"
xpos 290
ypos -208
}
Dot {
name Dot8
xpos 324
ypos -102
}
set Nd04b4000 [stack 0]
Dot {
name Dot9
xpos -1436
ypos -102
}
Dot {
name Dot10
xpos -1437
ypos 2149
}
Dot {
inputs 0
name Dot14
xpos -1106
ypos 283
}
push $Nd04b4000
Log2Lin {
operation lin2log
black 4e-05
white 665
name Log2Lin1
label "\[if \{\[value operation]==\"lin2log\"\} \{return \"LIN > LOG\"\} else \{return \"LOG > LIN\"\}]"
xpos 290
ypos -23
disable {{!parent.lin2log}}
}
Dot {
name Dot6
xpos 324
ypos 152
}
set Nd04efc00 [stack 0]
Dot {
name Dot1
xpos 34
ypos 152
}
set Nd0498380 [stack 0]
Dot {
name Dot2
xpos -84
ypos 152
}
set N89364380 [stack 0]
Dot {
name Dot3
xpos -204
ypos 152
}
set Nd04c2e00 [stack 0]
Dot {
name Dot11
xpos -552
ypos 152
}
set Nd04bea80 [stack 0]
Dot {
name Dot13
xpos -957
ypos 152
}
add_layer {cleanplate cleanplate.r cleanplate.g cleanplate.b}
Copy {
inputs 2
from0 rgba.red
to0 cleanplate.r
from1 rgba.green
to1 cleanplate.g
from2 rgba.blue
to2 cleanplate.b
name Copy2
xpos -991
ypos 260
}
Expression {
expr0 abs(r-cleanplate.r)
expr1 abs(g-cleanplate.g)
expr2 abs(b-cleanplate.b)
name Expression2
label DIFFERENCE
xpos -991
ypos 344
}
Remove {
channels cleanplate
name Remove1
xpos -991
ypos 396
}
Expression {
expr3 r+g+b
name Expression3
label "A = R+G+B"
xpos -991
ypos 450
}
Shuffle {
red alpha
green alpha
blue alpha
name Shuffle5
label "RGB = A"
xpos -991
ypos 503
}
Dot {
name Dot15
xpos -957
ypos 714
}
push $Nd04bea80
Expression {
expr3 ((parent.chroCol.r-r)**2+(parent.chroCol.g-g)**2+(parent.chroCol.b-b)**2)**(1/2.0)
name Expression1
label "DISTANCE MAP"
xpos -586
ypos 210
}
Shuffle {
red alpha
green alpha
blue alpha
name Shuffle4
label "RGB = A"
xpos -586
ypos 276
}
Dot {
name Dot12
xpos -552
ypos 598
}
push $Nd04c2e00
Shuffle {
green red
blue red
alpha black
name Shuffle3
label R
xpos -238
ypos 212
}
Multiply {
channels rgb
value {{parent.rMult}}
name Multiply3
label "\[value parent.rMult]"
xpos -238
ypos 268
}
Clamp {
name Clamp1
xpos -238
ypos 316
}
Dot {
name Dot5
xpos -204
ypos 378
}
push 0
push $N89364380
Shuffle {
red green
blue green
alpha black
name Shuffle2
label G
xpos -118
ypos 212
}
Multiply {
channels rgb
value {{parent.gMult}}
name Multiply2
label "\[value parent.gMult]"
xpos -118
ypos 268
}
Clamp {
name Clamp2
xpos -118
ypos 318
}
Dot {
name Dot4
xpos -84
ypos 378
}
push $Nd0498380
Shuffle {
red blue
green blue
alpha black
name Shuffle1
label B
xpos 0
ypos 212
}
Multiply {
channels rgb
value {{parent.bMult}}
name Multiply1
label "\[value parent.bMult]"
xpos 0
ypos 268
}
Clamp {
name Clamp3
xpos 0
ypos 318
}
Merge2 {
inputs 3+1
operation plus
name Merge1
xpos 0
ypos 426
}
Dot {
name Dot7
xpos 34
ypos 511
}
push $Nd04efc00
Switch {
inputs 2
which {{parent.customLum}}
name Switch1
xpos 290
ypos 507
}
Switch {
inputs 2
which {{"\[if \{\[value parent.keyerOp]==\"Chrominance Key\"\} \{return 1\} else \{return 0\}]"}}
name Switch2
xpos 290
ypos 590
}
Switch {
inputs 2
which {{"\[if \{\[value parent.keyerOp]==\"Difference Key\"\} \{return 1\} else \{return 0\}]"}}
name Switch3
xpos 290
ypos 710
}
Keyer {
operation "luminance key"
name Keyer1
xpos 289
ypos 981
}
Dot {
name Dot16
xpos 323
ypos 1194
}
set N90a4d880 [stack 0]
Dot {
name Dot17
xpos -116
ypos 1190
}
Shuffle {
red alpha
green alpha
blue alpha
name Shuffle6
label "RGB = A"
xpos -150
ypos 1252
}
Dot {
name Dot18
xpos -116
ypos 1338
}
set N8c643880 [stack 0]
Dot {
name Dot19
xpos -264
ypos 1338
}
set N579a700 [stack 0]
Dot {
name Dot21
xpos -404
ypos 1338
}
Shuffle {
red white
green white
blue white
alpha white
name Shuffle7
label "RGBA = 1"
xpos -438
ypos 1382
}
Multiply {
value {{parent.bumpSub}}
name Multiply4
label "\[value parent.bumpSub]"
xpos -438
ypos 1437
}
Dot {
name Dot22
xpos -404
ypos 1506
}
push $N579a700
Blur {
size {{parent.bumpBlur}}
name Blur1
label "\[value parent.bumpBlur]"
xpos -298
ypos 1376
}
Merge2 {
inputs 2
operation from
name Merge3
xpos -298
ypos 1502
}
Expression {
expr3 abs(a)
name Expression4
label ABS(A)
xpos -298
ypos 1550
disable {{!parent.bumpA}}
}
Dot {
name Dot20
xpos -264
ypos 1615
}
push $N8c643880
Merge2 {
inputs 2
operation from
name Merge2
xpos -150
ypos 1670
}
Dot {
name Dot23
xpos -116
ypos 1742
}
push $N90a4d880
Switch {
inputs 2
which {{"\[if \{\[value parent.keyerOp]==\"Bump Keyer\"\} \{return 1\} else \{return 0\}]"}}
name Switch4
selected true
xpos 289
ypos 1742
}
Copy {
inputs 2
from0 rgba.red
to0 rgba.red
from1 rgba.green
to1 rgba.green
from2 rgba.blue
to2 rgba.blue
name Copy1
xpos 289
ypos 2126
disable {{curve}}
}
Clamp {
channels alpha
name Clamp4
xpos 290
ypos 2327
disable {{!parent.clamp}}
}
Output {
name Output1
xpos 289
ypos 2470
}
end_group
Xabier Arrieta Alaez 