> For the complete documentation index, see [llms.txt](https://docs.marpledata.com/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.marpledata.com/docs/marple-db/datastreams/preprocessing-rules.md).
# Preprocessing rules
A datastream can be configured with preprocessing rules. These allow you to clean your data into a Unified Name Space (UNS).
Per signal, you can configure
* **Output name**: a new name for the signal
* **Description**, will be added as signal metadata
* **Unit**
* **Gain and Offset**, applying the formula `new_value = input_value*gain + offset`
Additionally, you can choose the priority of a signal
* **High**: 1) the signal will be imported first when importing a file, and 2) the signal will also be loaded into hot storage automatically
* **Default**: no special treatment
### Discover Preprocessing in 1 minute
{% embed url="" %}
Want to discover more Marple features in 1 minute? Check out other [1 Minute Marple videos](/docs/other-resources/1-minute-marple-videos.md)
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