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# GammaParams

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

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

## Contains

No content.

## Contained By

- Gamma

## Attributes

channel
  The color channel to apply gamma correction to. Possible values are "R", "G", and "B". Optional.

  If this attribute is not specified, the gamma correction is applied to all channels.

gamma
  The power value to use. Valid values range from 0.1 to 10.0 inclusive. Required.
offset
  The offset to use. Valid values range from 10–6 to 0.9 inclusive. Optional.

  If it is used, the Gamma element's style attribute should be set to "moncurveFwd" or "moncurveRev". Othewise, the style attribuute should be "basicFwd" or "basicRev".

## 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 Offet

    <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>

### Separate Channels

    <ProcessList id="id">
        <Gamma inBitDepth="32f" outBitDepth="10i" style="basicRev">
            <GammaParams channel="R" gamma="2.4" />
            <GammaParams channel="G" gamma="2.35" />
            <GammaParams channel="B" gamma="2.2" />
        </Gamma>
    </ProcessList>