# Android: Screen sharing via HDMI

**Solution:**

- Share the tablet screen to a Notebook via HDMI.
- The Notebook uses the shared screen 
    - a) like a 'webcam' or
    - b) shows the shared screen and reshare the window.

**Comparison**

- A similar setup can be reached with

#### Hardware

1. Android Tablet with USB-C connector (Samsung Galaxy S4, S6).
2. USB-C / HDMI Adapter (plugged into the tablet)
3. HDMI cable (between 2 and 4)
4. HDMI capture stick (plugged into the notebook). If the USB port of the HDMI capture stick is to big, use an USB extension.

[![tablet-hdmi-capture.png](https://wiki.math.uzh.ch/public/uploads/images/gallery/2026-06/tablet-hdmi-capture.png)](https://wiki.math.uzh.ch/public/uploads/images/gallery/2026-06/tablet-hdmi-capture.png)

#### Use with BBB in a Y27 seminar room

**Part 1: Setup BBB**

- Power on the Seminar room laptop.
- Open the browser.
- Login to MY > start a BBB stream (or use MS-Teams, Zoom).
- Share the notebook screen in BBB - or just the *guvcview* window (see below).
- Students in the room: switch on the beamer (small black box, takes 2 minutes to power on).

**Part 2: Share tablet screen**

- Connect the tablet with HDMI Capture stick to the notebook (see hardware above).
- Samsung: **do not use Samsung DeX** .. *the tablet will act as a notebook, not as a tablet (in this scenario more disadvantage than advantage)*.
- Start `guvcview` (webcam icon on the left panel) 
    - Select the right video source: 
        - On tab *Video Controls* select device: *USB Video: USB Video*.
        - There are probably two (same name), check both.
        - A popup appears: *Launch new process or restart?* >> **restart**.
- Resolution: 1920x 1080
- Keep the *guvcview* open. To bring the tablet share window to front, click in it.

[![guvcview.png](https://wiki.math.uzh.ch/public/uploads/images/gallery/2026-06/guvcview.png)](https://wiki.math.uzh.ch/public/uploads/images/gallery/2026-06/guvcview.png)

**Conclusion:**

- The notebook webcam can still show the speaker.
- A window (=guvcview) is the tablet screen.
- The quality should be fine for streaming as well as beamer presentation (both at the same time).
- The seminar room microphones are used as regular.