Nuke: Per Shot Grade

npsg.py

import nuke


def main(node):
    node["selected"].setValue(False)
    average_intensity = 0
    keys = 0
    for channel in node["intensitydata"].animations():
        for key in channel.keys():
            average_intensity += key.y
            keys += 1
    
    average_intensity /= keys
    
    # Disable per frame grade node.
    per_frame_node = node.dependent(nuke.INPUTS)[0]
    per_frame_node["disable"].setValue(True)
    
    # Create per shot grade node.
    per_shot_node = nuke.createNode("Grade")
    per_shot_node["selected"].setValue(False)
    per_shot_node.setInput(0, per_frame_node)
    
    per_frame_node.dependent(nuke.INPUTS)[0].setInput(0, per_shot_node)
    
    per_shot_node["xpos"].setValue(per_frame_node["xpos"].value() + 100)
    per_shot_node["ypos"].setValue(per_frame_node["ypos"].value())
    
    per_shot_node["white"].setValue(nuke.toNode("Target_Intensity")["target_intensity"].value() / average_intensity)


curvetool_nodes = []
for node in nuke.selectedNodes():
    node["selected"].setValue(False)

    if node.Class() != "CurveTool":
        continue

    curvetool_nodes.append(node)

for node in curvetool_nodes:
    main(node)