# Intensity Filter and Picker

The intensity feature in a LAS file represents the strength of the laser pulse return from a surface when captured by a LiDAR sensor. Think of it like how a flashlight reflects differently off various surfaces, bright surfaces reflect more light, while dark surfaces reflect less.

{% hint style="success" %} <img src="https://3895963154-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTcOUG6rfWxqGM0N4db2P%2Fuploads%2FGOAkLkFFY9H0DEt10649%2Fbold_idea_icon.png?alt=media&#x26;token=5e795075-b5f4-4e03-a9dd-c01069ceac8b" alt="" data-size="line"> Typically stored as a 16-bit integer (0 to 65,535). Higher values mean stronger reflections.
{% endhint %}

![Intensity animation](https://content.gitbook.com/content/TcOUG6rfWxqGM0N4db2P/blobs/vj7YVNKtou2J1r7DW2Qd/image)

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### Benefits

* Material classification: Helps distinguish between different materials.
* Road and infrastructure mapping: Enhances visibility of lane markings.
* Vegetation / water bodies analysis: Differentiates between tree types and water bodies.

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### Steps to use Intensity Filter

{% stepper %}
{% step %}

### Open point color settings

Go to Tool Settings -> Point Colors
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{% step %}

### Select an intensity color map

Choose one of the available intensity filters:

* Intensity (B-G-Y-R)
* Intensity (B-C-T-G-Li-Y-O-R)
* Intensity (Rainbow)
* Intensity Grayscale
  {% endstep %}

{% step %}

### Pick an intensity from the point cloud

Identify an area that has a reflective surface but shows low intensity. Use the intensity picker by pressing CTRL+Shift+left-click on the point cloud to pick the intensity value of a point. This action is called the Intensity Picker.
{% endstep %}

{% step %}

### View picked intensity feedback

A message appears informing you of the intensity value picked.
{% endstep %}

{% step %}

### Intensity Controls Slider adjustments

When you pick an intensity:

* The Intensity Controls Slider minimum is set to (picked intensity - 1) or 0, whichever is higher.
* The Intensity Controls Slider maximum is set to (picked intensity - 1) or 100, whichever is less.

You can further adjust the range using the slider or the min and max input fields.
{% endstep %}

{% step %}

### Observe the point cloud coloring

Points whose intensity values lie within the Intensity Controls Slider range will appear with sharpened intensity colors. The remaining points will be blue and/or red.
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### Tip for low-intensity views

When intensity values are very low, the color schema can be straining on the eyes. Use the Isolate feature to reduce color noise. The [Hotzone](https://docs.imerit.net/3d-multi-sensor-fusion/labeling/3d-multi-sensor-fusion-labeling-editor/key-features/hotzone) feature can also be applied before picking an intensity.
{% endstep %}
{% endstepper %}