# How to rotate a video?

{% embed url="<https://www.youtube.com/watch?v=wYQeTk6GmB4>" %}
**YouTube:** Quickstart on Raspberry Pi 4 to produce vertical video with filter.
{% endembed %}

In this video, a 16:9 video is rotated 90° using the datarhei Restreamer streaming server. In the video settings of the active channel, the encoding is changed to 9:16. There are different rotation presets available. In the example, a Raspberry Pi 4 is used, which performs the encoding via the GPU OpenMax.

{% hint style="info" %}
An encoding of the video is always necessary to get rotated video output.
{% endhint %}

## Prerequisite

You have already started your Restreamer and added a video source.

### Step 1

Edit the video source settings.

### Step 2

Start encoding

### Step 3

Various setting options are available besides rotation, also horizontal and vertical flipping.

![Fig 1: Various setting options are available.](https://304400748-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-MS3qj4cW170AMeE1ckj-1703796690%2Fuploads%2F85EpVyyLIvfloapI4H2p%2FBildschirmfoto%202022-07-20%20um%2015.42.30.png?alt=media\&token=48c05405-4259-4411-84dc-462ce7239c10)

## Learn more

{% content-ref url="../../installing" %}
[installing](https://docs.datarhei.com/restreamer/installing)
{% endcontent-ref %}

{% content-ref url="../manual" %}
[manual](https://docs.datarhei.com/restreamer/knowledge-base/manual)
{% endcontent-ref %}


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