Gamma
The Gamma element applies a gamma correction to color values.
It is an Autodesk extension to the Academy/ASC XML color transform format.
Introduced
Version 1.2.
Contains
- Description. Optional, any number.
- GammaParams. Required, maximum three total.
- DynamicParameter. Optional, no more than one. The param attribute must be set to "DEFAULT_LOOK".
Contained By
Attributes
id, name, bypass, inBitDepth, outBitDepth
See Common Operator Attributes.
style
Specifies the type of power law curve. Required.
Note: The following equations assume that the input and output bit-depths are floating-point. For integers, the values are normalized to [0.0, 1.0]. In other words, the gamma and offset values stored in the CTF file do not depend on the input and output bit depths.
| Value | Meaning |
|---|---|
| "basicFwd" | Applies the power law with the gamma value specified in the GammaParams element. The GammaParams element must not have an offset attribute.
|
| "basicRev" | Applies the power law with the inverse of gamma value. The GammaParams element must not have an offset attribute.
|
| "moncurveFwd" | Applies a function that has a linear segment near the origin (black) and a power-law segment at higher values. At the junction, the curve is continuous in both value and tangent. This type of curve is used in the Rec. 709, sRGB, and CIE L* equations. The GammaParams element must have an offset attribute.
|
| "moncurveRev" | Applies a function that has a linear segment near the origin (black) and an inverse power-law segment at higher values. The GammaParams element must have an offset attribute.
|
