50 lines
2.6 KiB
Markdown
50 lines
2.6 KiB
Markdown
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# Auto Exposure
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The **Auto Exposure** effect simulates how the human eye adjusts to changes in brightness in real-time. To do this, it dynamically adjusts the exposure of an image to match its mid-tone.
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In Unity, this effect generates a histogram on every frame and filters it to find the average luminance value. This histogram and the **Auto Exposure** effect requires [Compute shader](https://docs.unity3d.com/Manual/class-ComputeShader.html) support.
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### Properties
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**Exposure** settings:
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| Property | Function |
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| :--------------------- | :------------------------------------------------------------ |
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| Filtering | Set the lower and upper percentages of the histogram that find a stable average luminance. Values outside of this range will be discarded and won't contribute to the average luminance. |
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| Minimum | Set the minimum average luminance to consider for auto exposure in EV. |
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| Maximum | Set the maximum average luminance to consider for auto exposure in EV. |
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| Exposure Compensation | Set the middle-grey value to compensate the global exposure of the scene. |
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**Adaptation** settings:
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| Property | Function |
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| :---------- | :------------------------------------------------------------ |
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| Type | Select the Adaptation type. **Progressive** animates the Auto Exposure. **Fixed** does not animate the Auto Exposure. |
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| Speed Up | Set the Adaptation speed from a dark to a light environment. |
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| Speed Down | Set the Adaptation speed from a light to a dark environment. |
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### Details
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Use the `Filtering` range to exclude the darkest and brightest part of the image so that very dark and very bright pixels do not contribute to the average luminance. Values are in percent.
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`Minimum`/`Maximum` values clamp the computed average luminance into a given range.
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You can set the `Type` to `Fixed` and it will behave like an auto-exposure setting.
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You can debug the exposure in your scene with the **Post-process Debug** component. To do this, add the **Post-process Debug** component to your Camera and enable the **Light Meter** monitor.
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The Light Meter monitor creates a logarithmic histogram that appears in the **Game** window. This displays information about the exposure in your scene in real time. For more information, see [Debugging](#Debugging).
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The Light Meter monitor.
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### Requirements
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- Compute shader
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- Shader model 5
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