# Compute lidar metrics (vector)
<!-- <div class="algorithm-id">
<strong>Algorithm ID</strong>: <code>hedgetools:lidarfeaturemetrics</code>
</div> -->
```{container} algorithm-id
**Algorithm ID**: `hedgetools:lidarfeaturemetrics`
```

Compute a set of choosen lidar derivated metrics on each polygon of the given polygon layer from COPC point cloud files. COPC files are point clouds files optimized for spatial request and can be created from common LAS/LAZ files using QGIS [pdal:createcopc](https://docs.qgis.org/3.44/fr/docs/user_manual/processing_algs/qgis/pointclouddatamanagement.html#create-copc) algorithm. The full list of available metrics is given [here](./lidar_metrics.md).


## Parameters

| Label                                        | Name           | Type                                                       | Description                                                                                                                                 |
| -------------------------------------------- | -------------- | ---------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------- |
| COPC lidar files                             | `LIDAR_FOLDER` | [folder]                                                   | Folder with COPC lidar files.                                                                                                               |
| Polygon layer                                | `HEDGES`       | [vector: polygon]                                          | Layer with target features where to compute metrics.                                                                                        |
| Metrics                                      | `METRICS`      | [string]                                                   | JSON string containing metrics with parameters. Choice of metrics is made using `Metrics` panel.                                            |
| Lidar preprocessing operations <br> Optional | `OPERATIONS`   | [string]  <br> Default: None                               | JSON string containing preprocessing operations with parameters. Choice of operations is made using `Lidar preprocessing operations` panel. |
| Strata bounds                                | `BINS`         | [string]                                                   | Strata bounds. Bounds should be separated with `,` and decimals mark after `.`.                                                             |
| Voxel X size                                 | `VOXEL_X`      | [numeric: double] <br> Default: 10                         | Size of voxels on X axis.                                                                                                                   |
| Voxel Y size                                 | `VOXEL_Y`      | [numeric: double] <br> Default: 10                         | Size of voxels on Y axis.                                                                                                                   |
| Voxel Z size                                 | `VOXEL_Z`      | [numeric: double] <br> Default: 0.5                        | Size of voxels on Z axis.                                                                                                                   |
| Parrallel threads                            | `WORKERS`      | [numeric: integer]                                         | Number of parrallel threads.                                                                                                                |
| Polygon layer                                | `OUTPUT`       | [vector: polygon] <br> Default: `[Create temporary layer]` | Output layer. Same as input polygon layer with additionnal fields depending on computed metrics.                                            |

## Outputs

| Label         | Name     | Type              | Description                              |
| ------------- | -------- | ----------------- | ---------------------------------------- |
| Polygon layer | `OUTPUT` | [vector: polygon] | Polygon layer with lidar metrics fields. |