# Merged Point Cloud

The Merged Point Cloud feature allows users to see all the points over time (across all the [frames](/project-setup/pre-process-data.md#data-terminology) of a [batch](/project-setup/pre-process-data.md#data-terminology)) aggregated in the same coordinate system of the current frame resulting in one big point cloud. Therefore, **ego motion** data is mandatory for this type of scene.

{% hint style="success" %} <img src="/files/iAfqrynDsFkwpijZxywW" alt="" data-size="line"> It is used on sequential tasks to annotate stationary objects in a single .&#x20;
{% endhint %}

By enabling the MPC, it's easy to detect and label all the stationary objects since they appear denser and brighter. While moving objects will leave a trail of points.

<figure><img src="/files/cBOUWg9YplDKCovKbLME" alt=""><figcaption></figcaption></figure>

## Benefits <a href="#toggle-the-merged-point-cloud-view" id="toggle-the-merged-point-cloud-view"></a>

* **Improve Efficiency:** By allowing all data points to be merged in a single frame, the user no longer has to traverse the sequence to find the ideal frame where the most points of the object are captured.
  * Static objects are also much clearly visible with the accumulated points
* **Improve Accuracy:** By integrating data from multiple frames, merged point clouds can enhance the accuracy of object annotation. Annotators can use the combined data to make more informed decisions about the precise location of objects within the point cloud.

## Steps to use MPC <a href="#toggle-the-merged-point-cloud-view" id="toggle-the-merged-point-cloud-view"></a>

1. Toggle the MPC switch on the header of the annotation tool. This will aggregate and merge points across all the [frames](/project-setup/pre-process-data.md#data-terminology) of the [batch](/project-setup/pre-process-data.md#data-terminology), by default on the next 20 frames.
   * The Multi Sensor Fusion tool supports various mechanisms of aggregating the point clouds across the sequence:
     * all&#x20;
     * [partial merged point cloud](#partial-merged-point-cloud)
     * using frame jump length
2. Identify the stationary object (that is dense and bright)
3. Select the [drawing tool](https://docs.imerit-prod.io/annotation-tool/key-features/pages/paJknzjTNlzvWVaCQ2EI#id-2.-drawing-tool) and create the annotation on the object
   * If the annotation is a [cuboid](/annotation-tool/drawing-tools/cuboid.md), it is propagated across all the frames.
   * If the object ceases to exist before the end of the frame, delete the annotation by right-clicking on it and selecting the delete option.

<figure><img src="/files/MtxJn5eqPJfbNHmL8EjN" alt=""><figcaption></figcaption></figure>

### Partial Merged Point Cloud

MPC has further options for merging points across a range of frames.

* The tool provides multiple options&#x20;
  * select a predefined option from the list
  * use the customizable start/end frame and hit enter

<figure><img src="/files/FHUh7fvjCV01Ds31AcJI" alt=""><figcaption></figcaption></figure>

* After triggering the merged point cloud, the timeline introduces a yellow to indicate the frames that are merged.

<figure><img src="/files/IsVqgPayRWlqBfNedX8g" alt=""><figcaption></figcaption></figure>


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.imerit-prod.io/annotation-tool/key-features/merged-point-cloud.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.