My friend Andy pointed me at this $15 HDMI capture device. I don’t have an immediate need for something like this, but it is so inexpensive, and I figured it might come in handy, so I had to try it out!

HDMI to USB Example

The Etermal capture card shows up in Linux as a MACROSILICON USB video capture device. It worked fine in guvcview and OBS Studio. I had to adjust the color space to get 30 frames per second out of it, but once I did, it seemed to work fine. I was also able to capture audio after setting it to 44.1 KHz.

HDMI to USB dmesg output

Why is this $15?!

You get what you pay for. This is a USB 2.0 device. It doesn’t do any video compression on the device either. That’s why it can only capture at 30 frames per second, while 1080p is actually 60 frames per second.

The manual says it will accept a 2160p30 or 1080p60 input. As far as I can tell, the output resolution and input resolution are independent. For my test, the easiest device I had nearby to plug in was an Amazon Fire TV. This Fire TV is set to output 1080p, and I was able to capture video cleanly at 480p, 1080p, and anything in between.

What am I going to use this for?

I figured it would let me use my Canon 6D DSLR as a webcam. I’ve had trouble with this in the past, though. The 6D doesn’t output 1080p. I’m pretty sure it will output 480p and something not unlike 720p. The last HDMI capture device I used was forcing the Canon to 480p. By the time you crop out the black bars, you aren’t left with many pixels.

I look forward to testing this out with my Canon 6D, but it will have to wait. My only compatible HDMI cable is attached quite well to my monitor stand, so I won’t be able to do the test today!

For me, the key aspect of this device is that it works out of the box on Linux.