a journal of interesting technical ideas . . . a journal of interesting technical ideas . . .
A little bit of fun today. There are many cases where we need to access different computers but can’t setup something like RDP. I had the idea to try this via video capture, so here’s my experience.
I ordered the Extenuating Threads HDMI Capture Dongle from Amazon for $14. There are several options available - I went with Extenuating Threads because it was cheap and I wouldn’t be out much if it didn’t work. I needed to capture 4k at least 30Hz and this model promises 4k at 60Hz.
The Dongle arrived and presented itself as a video source (like a camera) once plugged in. In fact, I could use the second computer video and route it into any application, including Teams. Identifying the dongle is pretty easy - I just flipped through all the available video sources in OBS or Cheese. You can also do this from the command line:
sudo apt-install v4l-utils #install Video for Linux tools
v4l2-ctl --list devices
My output looked like this:
USB Video: USB Video (usb-0000:00:14.0-1):
/dev/video0
/dev/video1hu
/dev/media0
I tested this with a number of video players, including OBS, MPV, mplayer and VLC. All three worked, but only OBS provided a decent frame rate and audio. OBS seems like a lot to load, just to see a remote server. My son suggested Ccdheese and I was skeptical, but that was actually far and away the most responsive. I used a Bluetooth mouse and keyboard to control the host and Cheese presented the display at realtime speeds but didn’t capture audio. I didn’t have any issues or artifacts with the display, even at 4k. I ended up dialing the resolution down to 1920x1080 so that it fit into a quarter of my 4k display and this worked perfectly.
I made this a little less temporary by replacing the seperate mouse and keyboard with a USB switch that let me toggle my controls back and forth between my main machine and the captured device.
So my cheap $14 USB dongle works to allow me to access a machine here in my office. I can treat the dongle as a video source and access it using most programs. Speed was good, but only Cheese and OBS allowed interactive speed. All told, a cute little experiment!