# How do I stream to HDMI?

Writing video data to the HDMI port is done with the `Framebuffer` publication service. After creating a channel in Restreamer, you can add the `Framebuffer` publication service. This publication services require that at least one framebuffer device is availbale on your system.

A framebuffer device is located in `/dev` with the name `fb*`, where `*` is a number usually starting from `0`.

The framebuffer device might only show up as soon a display is connected.

In order to have these devices available in the Restreamer Docker container, you have to start the container with the `--privileged` option.

#### Raspberry Pi 4

On a Raspberry Pi 4 we recommend to install Raspbian "bullseye" in order to enable the framebuffer device `/dev/fb0`.

You have to edit the `/boot/config.txt` in order to set the correct resolution:

1. Open `/boot/config.txt` in an editor, e.g. `sudo nano /boot/config.txt`
2. Set `hdmi_force_hotplug=1`
3. Set `hdmi_group=1`
4. Set `hdmi_mode=4` (for 1280x720) or `hdmi_mode=16` (for 1920x1080)
5. Set `hdmi_pixel_encoding=2`
6. At the bottom in the `[pi4]` section, set `dtoverlay=vc4-fkms-v3d`

Reboot the Pi and the docker container. Now you should see the `Framebuffer` publication service, where you select the `/dev/fb0` device and the matching color settings (usually `RGB565 Little Endian`).


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