Equalize Copernicus node

Equalizes colors by stretching or shifting their range.

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Parameters
Inputs
Outputs

This operation adjusts colours by shifting or scaling them. It can do so to make them fit a given range or re-anchor them.

This is useful when an unknown input range needs to be fit into a specific range.

Care should be taken in procedural setups as changes to the input may have surprising effects if some frames suddenly have extreme values. It is almost always better to use a Remap COP with a fixed range. It is also considerably faster to use Remap COP as it doesn’t need to do the range computation.

Parameters ¶

Signature

The layer type that the source accepts.

See Signatures for more information.

Mask

The amount of the new value to mix in with the original value. Higher values mix in more of the new value. Lower values mix in less of the new value. You can also set the RGBA channels to which you apply the effects of this node.

The default value is 1, which means this node uses only the new value. See Mask for more information.

Toggle RGB

Turns the Red, Green, and Blue channels on and off.

Red (default)

Applies this node’s effects to the Red channel.

Green (default)

Applies this node’s effects to the Green channel.

Blue (default)

Applies this node’s effects to the Blue channel.

Alpha (default)

Applies this node’s effects to the Alpha channel.

Equalize By

Stretch to Black and White

The minimum and maximum values found in the image are mapped to black and white, or 0 and 1.

Move Minimum to Black

The colors are adjusted so the minimum value is black, 0.

Move Maximum to White

The colors are adjusted so the maximum value is white, 1.

Move Average to Value

The colors are adjusted so the average luminance matches the given value.

Scale to Maximum Length

The colors are scaled so the maximum luminance matches the provided value.

Fit Method

When a certain color is moved to a goal value, this can be done either by shifting all the colors, or by scaling all the colors.

Shifting Values

Match the goal value by adding the difference to all pixels.

Scaling Values

Match the goal value by scaling all pixels by the ratio.

Luminance Type

SGI Luminance

This is a historical luminance computation used in Houdini, which is believed to originate with SGI.

lum = 0.3086 * red + 0.6094 * green + 0.0820 * blue

NTSC Luminance

The standard NTSC luminance computation. This is probably the most commonly used luminance options.

lum = 0.299 * red + 0.587 * green + 0.114 * blue

HDTV Luminance

The HDTV standard luminance from BT 709.

lum = 0.2126 * red + 0.7152 * green + 0.0722 * blue

Average

An average of the channels.

Maximum Channel

The maximum of the channels.

Minimum Channel

The minimum of the channels.

Magnitude / Length

The length of the vector formed by taking the channels as components. For Mono input, this is the absolute value.

Hue

Convert to HSV and return the hue channel.

Saturation

Convert to HSV and return the saturation channel.

Value

Convert to HSV and return the value channel.

Red

Extract the red, or x, channel

Green

Extract the green, or y, channel

Blue

Extract the blue, or z, channel

Alpha

Extract the alpha, or w, channel

Black

The value to use for black, normally zero.

White

The value to use for white, normally one.

Target Average

The goal average value.

Inputs ¶

source

The layer to equalize.

active

Mono layer of pixels to contribute to computing the range of the equalization. Pixels with a value > 0.5 will be considered.

mask

An optional per-pixel mask amount that’s scaled by the Mask parameter.

Outputs ¶

equalize

Equalized layer.

Parameters ¶

Inputs ¶

Outputs ¶

Copernicus nodes