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# Gamma

The Gamma element applies a gamma correction to color values.

It is an Autodesk extension to the Academy/ASC XML color transform format.

## Contains

In order:

- Description. Optional, any number.
- GammaParams. Required, maximum three total.

## Contained By

- ProcessList

## Attributes

id, name, inBitDepth, outBitDepth
  See Common Operator Attributes.
style
  Specifies the type of power law curve. Required.
  NoteThe 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 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 noth 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.

## Example

### Without Offset

    <ProcessList id="9e999646-3e76-4374-814c-e4c46c6438de" version="1.2">
        </Matrix>
        <Gamma inBitDepth="32f" outBitDepth="12i" style="basicRev">
            <GammaParams gamma="2.400000000000000" />
        </Gamma>
    </ProcessList>

### With Offset

    <ProcessList id="1b86aac2-1fdb-4dd8-bc6b-54f3551b9bd4" version="1.2">
        <Gamma inBitDepth="32f" outBitDepth="32f" style="moncurveFwd">
            <GammaParams gamma="2.600000000000000" offset="0.050000" />
        </Gamma>
    </ProcessList>

#### Topics in this section

- GammaParams

  The GammaParams element defines the gamma value and optional offset for a Gamma element.