This started off as a project to rig together a video calling setup with an existing camera + capture card, as a cheaper alternative to buying an expensive Logitech webcam. In the initial months of confinement there was a rush on people buying webcams for remote working, it caused a supply/demand shock that pushed up prices.
In early May, the Logitech C920s webcam was selling on Amazon for around £85, and Amazon finally ran out of stock in late May. Third party sellers continued to sell the webcam, the price spiked to just over £400 in early June, and back down to around £150 today. The cheaper Logitech C270 webcam remained in stock, yet the price went from £17.50 in January-February to £44.50 through June. These prices are wacky enough to prompt people like me to look around for creative alternatives.

Most professional streamers with a budget seem to have settled on an Elgato Cam Link connected to some kind of fancy DSLR camera. I used to have a Blackmagic capture card, and one of the (Korean?) EasyCap dongles, back when I was doing a lot of video capture. So I’m already familiar enough with the idea.

HDMI capture

An Elgato Cam Link would still be too expensive at £120, so I bought this HDMI to USB dongle for £12. I can’t tell much about it, the seller is registered somewhere in Shenzhen, otherwise it’s listed on Amazon as ‘no branded’ and that’s accurate, I have no idea who the manufacturer is.

HDMI_capture_card

Despite every impression that it’s some kind of cheap knockoff, I was really impressed with this. The electronics are in a metal case, and held in with what look like M3 standard screws (this is a wild guess, I haven’t measured them). Of course I took it apart.

HDMI_capture_card_internals

There’s a date printed on the circuit board, it reads 2020-05-11. I assume my dongle was shipped relatively fresh from the factory. I tested it once on Ubuntu, and it worked out of the box. It doesn’t work on my Pinebook running Manjaro, but I suspect that’s more down to the general instability of my Manjaro system than anything else.

The first critical problem was that my existing camera didn’t output an image from the sensor over HDMI. I’ve got a point-and-shoot Fujifilm FinePix XP130 and the Micro-HDMI output is apparently only there for displaying photos on your TV? What a pointless feature. If the camera has a video out, I want to actually use it! 😠

Camera

At this point I could have given up, but instead decided to look about for another camera which does what I need. I emailed a couple of action cam manufacturers. Akaso confirmed that their Brave 6 camera does output a live image from the sensor over HDMI. So I went ahead and bought one of those. With various discounts it came out at £60, plus a fast SD card.

akaso_brave_6_camera

For anyone else trying this, Campark told me that none of their cameras with HDMI output can be used for streaming video. So, don’t buy their stuff. Although it was nice of them to reply in detail to my questions.

Here’s what the Brave 6 looks like connected to a Microsoft Surface tablet.

webcam_setup

It can be powered directly over USB without the battery plugged in too, if that’s a concern.

Overall, the total cost was ~£93.50:

The final bill comes out comfortably lower than a Logitech C290s currently going for £150. Plus, I’ve now got an action camera, and I’ve always wanted to have one of these.

Videos

Here is what I’ve been doing with the camera. The first thing I filmed was Matthieu running around Port Meadow.

Next, I took it out when canoeing. I attached the camera to my chest, round the buoyancy jacket, it ended up swaying a lot with my body and pretty much just ended up filming my knees. I need some way to attach it directly to the boat.

This was recorded at 60fps, and when compressing for use here, I set FFMpeg to interpolate frames down to 30fps. Using this video filter minterpolate=fps=30:mi_mode=mci:mc_mode=aobmc:me_mode=bidir:vsbmc=1. Does it look any smoother? Or has it just deleted the extra frames? I can’t tell.

The camera has a time lapse mode. Yesterday evening I cycled out onto Port Meadow and filmed the sunset.

It also has a setting for higher frame rates up to 120fps. I could film something in slow motion, but don’t have any opportunities for that yet.

Camera review

Finally, here’s what I think of the camera itself.

Pros:

Cons:

It’s probably worth acknowledging the critical flaws in this whole concept. If your laptop already has a webcam, it’s not worth going through all this just for the minor increase in image quality. The capture card introduces latency, and some distortion from compression, and finally… if you’re on a zoom call with 8 other people on screen, nobody is really going to notice the difference.