To use your Linux computer’s HDMI port as a video grabber (i.e., to capture video from an external HDMI source) without additional physical hardware, you generally need:
- A capture device (usually a USB or PCIe HDMI capture card), because HDMI ports on computers are typically output-only and cannot be used as input for capturing video.
Why You Can’t Use HDMI Port as Input
- HDMI ports on PCs/laptops are designed for output (sending video to a monitor/TV), not input.
- HDMI input requires dedicated hardware (a capture card) to decode and process the incoming signal.
Possible Workarounds (No Additional Hardware)
1. Use a Laptop with HDMI-In (Rare)
- Some high-end laptops (e.g., certain Dell Precision or HP ZBook models) have HDMI-in ports, but this is very rare.
- If your laptop has this, you can use software like OBS Studio or VLC to capture the input.
2. Use a USB-C/Thunderbolt Port with Alt Mode
- If your computer has a USB-C or Thunderbolt port with HDMI Alt Mode, you might be able to use a USB-C to HDMI adapter to capture video, but this is still output-only in most cases.
- Some newer laptops support USB-C capture devices (e.g., Elgato Cam Link), but this still requires an external device.
3. Network Streaming (No HDMI Capture)
- If the source device (e.g., camera, game console) supports network streaming (RTMP, RTSP, NDI), you can capture the stream over your local network using software like OBS Studio or FFmpeg.
Software Options (If You Have a Capture Device)
If you do get a capture device, you can use:
- OBS Studio (Open Broadcaster Software)
- VLC (VideoLAN Client)
- FFmpeg (command-line tool)
Summary Table