> For the complete documentation index, see [llms.txt](https://docs.datarhei.com/restreamer/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.datarhei.com/restreamer/knowledge-base/user-guides/how-to-rotate-a-video.md).

# 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.](/files/GCFuQswZlarv0TQ83uu1)

## Learn more

{% content-ref url="/pages/-MXb\_BFQq0tV8S0Onai7" %}
[Installing](/restreamer/installing/minimum-requirements.md)
{% endcontent-ref %}

{% content-ref url="/pages/-M\_uA53Pks3B1GyDSBc8" %}
[Manual](/restreamer/knowledge-base/manual.md)
{% endcontent-ref %}


---

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