Turn any camera into a webcam with a $13 USB/HDMI video card | Hacker News Reader

Turn any camera into a webcam with a $13 USB/HDMI video card

photorumors.com

Not to self-promote, but the apps to make this possible for free have gotten much better over the last 8 months, and I feel they're less complicated than capture. I collected them here:

https://techcrunch.com/2020/06/10/how-to-get-your-nice-camer...

Of course there are lots of other guides out there too a search away.

It's pretty wild how rudimentary some are even now, but the major brands seem to work, with some quirks. Our video team also recommends (as others do) a dummy battery.

One issue you did not address in your otherwise solid article is the issue of audio sync latency IF you don't pass your audio via the camera's HDMI. This becomes an issue when you decide to use a nice mic/audio interface for higher quality audio but then you can have sync issues with the video. To mitigate audio sync issues, it's best to have the audio going into the camera's input. You can pass audio from a nice mic/preamp into the camera but it's less ideal than going into the computer via a decent audio interface. Afaik, OBS can fix those sync issues but it's quite a lot of effort to do all of this properly vs. buying a better webcam.

Interesting, we didn't have this issue during the virtual events and interviews I did - I used a separate USB mic, not a mic on the camera. So it did didn't occur to me.

But it seems quite correct that this could be an issue, and I'll add a note in the article.

Having used my Canon 80D as a webcam after Canon released a beta tool that made it possible to stream video over USB, I would personally recommend against trying this. Yes, it's doable, and yes the video quality is much better. But the logistics of mounting a full sized camera, or even most mirrorless cameras, to a desk somewhere close to your monitor is surprisingly annoying.

While a separate webcam perched on top of your monitor produces lower quality, it comes with fewer tradeoffs when you're not actively using it. I suspect that you need to be a professional streamer/youtuber before the tradeoffs make it make sense.

Pop it on a short tripod behind your monitor, surely? Why doesn't this work? People likely already have LED lights for video conferencing on similar stands in a similar place.

Edit: I tried what you recommend, and the resulting tradeoffs are part of why I don't recommend it anymore.

I'd have to rearrange the room to accomplish that, there is nowhere close to enough space behind my monitor to put a tripod. It would also block all the LED lights I have on the wall (I'm a bit obsessive on this subject), necessitating more changes. The wires also rapidly become annoying, since unlike a monitor-top webcam they can't be bundled up with the HDMI/Power for the monitor.

The further back the camera gets too, the less "real" it feels to your audience. Humans can tell where each others' eyes are focused, and the further the camera gets from the plane of where your eyes are focused (the monitor), the more it will feel like that you're not paying attention to them. This means the ideal place to put the camera is right on top of the monitor, exactly where we put webcams today. This might be doable with some cameras, but certainly mine is too heavy to pull this off. Perhaps a boom arm system would do the trick, at the minor cost of making my sit/stand desk less usable.

If you're going to try and use a real camera to improve video quality, I think you really need to go whole-hog and build a teleprompter setup. That's the right way to make it possible to see something and have your eyes focused on the right place without having to dodge around getting a monitor to work correctly. This is completely doable, albeit a bit excessive, but probably well beyond what's worth it for anyone but the most obsessive or those whose jobs involve being on camera a lot. Maybe if I was CTO it would be worth it just for extremely high-fidelity all-hands, but that's not my current situation.

> I'd have to rearrange the room to accomplish that, there is nowhere close to enough space behind my monitor to put a tripod.

My top tip is to use a full-size dining room table as your desk, rather than something sold as a modern desk. Then your monitor sits about in the middle of the table and you have so much space behind it, around the sides, and beside you. It's a huge improvement to have this extra space.

Things marketed as 'computer desks' are invariably about 4x too small for comfortable use and placing your equipment on.

This kind of gets into why I don't think it's worth the tradeoffs. You can get a desk big enough to support a tripod and monitor without sacrificing ergonomics, but then you have to have a massive desk. My current desk is 32" deep, and I'm certain that bringing the monitor close enough to make room for a tripod on the desk would involve bringing the monitor too close for comfort. In my specific case it would also necessitate giving up the gas-arm that my monitor is attached to since it only clips to the back of the desk, and I don't want to give that up.

You can make it work, if you rearrange your entire office space around this requirement. I personally wouldn't recommend it, but to each their own.

I suspect that computer desks are "too small" because a dining room table is a rather large object that doesn't fit well into small rooms or rooms that have anything else in them.

Probably. But given the time one spends staring at screens, even pre-covid that should be of no concern. I meanwhile solved that by getting a used drawing table for architects off auction. Electrically adjustable, even! And not looking shabby. This is a hugh part of my life, why should it be constrained by scroogery?

I did this a few years ago grabbing an ikea vastanby table. Unfortunately it I wouldnt really recommend it, or would at least recommend something else. The size of the top is great, but ergonomically it sucks, its far too high and non adjustable, and the supports for the top get in the way of a good sitting position, will be switching out to a large sit stand desk eventually, hopefully using the same worktop.

Are you aware of https://www.ergotron.com/en-us/products/mounts and the other offers they have? Obsess about that :-)

Without a proper G clamp, it is a quick way to lose a couple thousand dollars to a stray elbow.

You just need a wide angle lens, so it can be mounted on the desk without needing more space. I recommend anything between 16mm to 24mm focal length lens (based on 35mm equivalent). Using DSLR or mirrorless camera as webcam on desk is done by many, especially by Twitch streamers, Youtubers, and Zoomers who want quality video. Also check out EposVox (Youtuber) who has a great setup with such a small amount of space. He has great video and tips on such setup.

> You just need a wide angle lens, so it can be mounted on the desk without needing more space.

The issue was physical mounting room for the tripod, not focal length. When I did try using my Canon, I actually didn't use the widest setting on my lens. A 16mm equivalent lens would've given everyone a really nice view of my closet, which isn't something I want to do.

> Using DSLR or mirrorless camera as webcam on desk is done by many, especially by Twitch streamers, Youtubers, and Zoomers who want quality video.

As I said below, those are groups that are willing to make tradeoffs for extremely high video quality, especially streamers and youtubers as that's their job. For the rest of us however, the tradeoffs are probably not worth it.

...would've given everyone a really nice view of my closet, which isn't something I want to do.

Ever heard of virtual green screening?

DUDE! Diz iz HÄCKERNYUZ! And you are fussing about such basics?

Is it really such a hassle to get a gorilla pod, or some similar thing, and wind/clip/fasten it to whatever is there?

https://joby.com/us-en/gorillapod-flexible-camera-tripods/

I got mine from Rollei about a decade ago for about 12 to 15EUR IIRC, to have something small and light for my backpack when underway, instead of something professional. Still works. And I neither stream, or take pictures often. Just something to be have with me if the need arises.

Maybe for you. For me it was a matter of grabbing a battery and putting the rear of the camera on top of it to make it tilt down a bit.

If you are using a desk, simply putting a tripod behind a monitor works too.

This method works great with old iPhones using a cheap $20 lightning to HDMI adapter, and the CameraVision app. Also, if you want a detailed technical review of this capture card, you can check out my blog post:

https://www.naut.ca/blog/2020/07/09/cheap-hdmi-capture-card-...

How does this setup perform for latency?

You have a phone app displaying the camera input, iOS compressing that video stream to send it out over Lightning, the Lightning-to-HDMI dongle decoding that stream to HDMI, then HDMI pulled in on the capture card.

If you run it side-by-side with a real webcam, can you notice that the stream is out of sync at all?

Coincidentally I just got one to use as a console for a Raspberry Pi.

It works well, but bear in mind it introduces a ~650ms lag, so anything interactive (e.g. typing on a keyboard) becomes noticeable.

But for $13 you can't expect much more. Even a $200 Elgato HD60 S+ has 280ms lag, so 15x lower cost for half performance seems a good deal.

FWIW, out of sync video isn’t too much of an issue for video calls. I’ve worked the past 8 months with 800-1200ms latency on video (satellite) and 25-50ms latency on voice (VoLTE) combined.

The only issue is when someone is annotating while sharing their screen and moves too quickly.

Many cameras frustratingly do not have a clean HDMI out, cluttering the screen with icons and settings which commonly can’t be disabled.

Some of this apparently has to do with a european import law that considers digital still cameras consumer electronics and digital video cameras professional equipment subject to import tax.

You might be confused with the 30min recording time limitation, another annoying software-based limitation many cameras have. Starting from 30 minutes a camera was considered as a video camera and subject to an extra levy—this was scrapped not so long ago, and camera makers are starting to remove the limitation on their newer models.

Having clean HDMI or not is just a matter of market segmentation, it used to be a premium feature.

Canon is really bad in this regards—many camera’s don’t have clean HDMI and/or shut off the HDMI output after 30 minutes. Luckily CHDK allows to add clean HDMI and disable power off to the Canon M3 and a number of other cameras, worked like a charm for me.

https://chdk.fandom.com/wiki/CHDK https://chdk.setepontos.com/index.php?topic=13489.0

You may be able to crop out the edges... But agreed.

Some Canon cameras also render a focus square right in the center of the screen, or around any faces that it detects. Very inconvenient.

No it's mostly a developer issue.

I've done this with the Elgato Camlink 4k on linux with a Lumix G7 that has an HDMI output, and it's pretty nice. Sadly there's a bug in the firmware I think that reports a bad colorspace, but there are ways to pass it around using v4l loopback devices. It's really nice to have a tripod with a camera on it, and the lens can zoom in or out to show more of my room. Although depending on the camera and what mode it's in, the HDMI output can be quite different, causing headaches and crashes sometimes in apps like zoom.

I've also ended up using my dashcam for a timelapse camera, since I'm not driving much.

Also, in terms of audio, just as a PSA: please get and use earbuds or headphones for your meetings. It's not so much for you, but everyone else can hear the echo.

There's an ld preload hack that is simpler and potentially lower latency than the loopback device: https://github.com/xkahn/camlink

That's a US$500 camera, if I was going to spend that much money on a camera I would purchase one that comes with vendor software that turns it into a webcam, I think Fujifilm and Canon do have this. Or maybe you just had an expensive camera lying around, haha.

My setup for this purpose (on Linux Mint) uses that camera, a Lumix G7, which is indeed about $500, compared to a Logitech HD Pro webcam for about $100, it is totally worth it. I can pick up the Lumix, which uses my existing collection of micro four thirds lenses, and bring it on vacation or whatever, as opposed to the Logitech which is useless for any other purpose.

The reason the Lumix is good for this is because of the "clean" HDMI output, i.e. without any camera overlays. I added to this a micro HDMI to HDMI cable ($10), a DC coupler ($22), a cheap Neewer tripod ($35) and an HDMI capture card ($15). I've optimized the card[0] and set up udev rules to use the optimized settings every time I plug it in. If I want fancier settings I use OBS. It looks orders of magnitude better than any webcam.

The weakest link in the whole setup is the micro HDMI cable -- they all tend to be very rigid compared to the size of the connector and I already had to throw away one cable, it helps to attach all wires with velcro to the tripod to reduce wiggle.

[0] http://ciko.io/posts/cheap_usb_hdmi_2/

>That's a US$500 camera

yes, its on the cheaper side

>I would purchase one that comes with vendor software that turns it into a webcam

all currently available on the market offer vastly inferior experience, like 720p30 max

In the distance learning system I designed/integrated for the private school I teach at, we use these things to dump in video from a document camera (an "Elmo"--- Elmo TT-12) into OBS for compositing and then into Zoom. Some teachers have Chromecast, DVD players, etc, plugged into the video input on the Elmo, too-- it can be pretty amazing the different use cases you can meet with this cheap little toy.

(Details here https://medium.com/@mlyle_74064/inexpensive-telepresence-for... https://github.com/mlyle/ConfAutomation

before you run out and use this fact to justify buying a new camera, do some quick research. some cameras will overheat in video mode after a while.

Typically only when in recording mode. If the video is pass through you should be fine. You will however likely need a dummy battery you can plug in.

It won't be recording video to its SD card, just outputting the moving image you get in the little preview screen out of HDMI as well.

I guess the heat comes from the expensive encoding, which doesn't happen here. But yeah, the camera should ideally also be able to powered by cable and not just battery only. And it should have a setting so that the preview screen have no UI elements...

I think you need to compile a list of cameras that support this, I don't think any camera works.

For example ElGato has a list [1] of compatible cameras with their camlink product (which is much more expensive than this but whatever).

[1] https://www.elgato.com/en/gaming/cam-link/camera-check

If you have a Canon camera, there's an 80% chance you can fiddle with the firmware a bit to enable the feature. Otherwise, unless you're using some Nikon DSLR, pretty much any interchangeable lens camera will work.

Very useful if you already have a mirrorless camera (with clean HDMI out) and a tripod or other way to mount it.

I’ve deeply enjoyed using this card when doing webcasts. For another $20 for a power line adapter for my camera I’ve had fantastic video quality.

> mirrorless camera (with clean HDMI out)

sorry if this is a stupid question but I don't have much experience with cameras and recently learned that cameras have a limited lifespan when it comes to the shutter (the thing that opens and closes to let in light). It is apparently enough of a concern that people ask for this count when buying used.

So my question is: does a video in this HDMI out mode count as just one click? how does this work? Also can you completely avoid using a battery with a power line adapter?

I tried using an old Nexus 4 as a live streaming camera a while back but after a few weeks the battery bulged and the gorgeous glass back shattered.

does a video in this HDMI out mode count as just one click?

Effectively zero clicks:

Aside from rotary shutter options available on a few high-end (>$50,000) digital cinema camera models, video exposure time is controlled by sensor electronics; all other mechanical shutter mechanisms I'm aware of remain open when capturing video (for any combination of recording, HDMI out, in-camera LCD live view, or electronic viewfinder display).

Pedantically, I suppose you can count one click for a normally closed (DSLR) shutter and zero clicks for a normally open (mirrorless) shutter, though I have no idea if DSLR firmware actually bothers to do this.

I'd also guess that simply opening and eventually closing the shutter causes less wear and tear than a typical <<1 second still photo exposure.

Also can you completely avoid using a battery with a power line adapter?

Generally, yes; in cases where battery-free DC input is not otherwise available, inexpensive "dummy battery" adapters are typically available that pass power through the camera's battery contacts from an external source.

Check adapter compatibility before buying a camera, however; make sure that a compatible dummy adapter (a) exists, (b) doesn't physically interfere with camera operation (buttons, tripod mount, etc.) and (c) attaches without a significant risk of damage to the camera (e.g., if you plan to use the camera in anything other than a totally stationary position, you probably want to ensure the battery compartment door can be closed, removed, or otherwise secured when the dummy battery is connected).

> does a video in this HDMI out mode count as just one click

A mirrorless camera's shutter is only used during taking photos (and some cameras, like the Sony A7S2 which I own, can also run in "shutterless" aka silent mode, at a slight expense in picture quality). It will not be impacted at all if the camera is used exclusively for video.

> Also can you completely avoid using a battery with a power line adapter?

Not with Sony Alphas, they will drain the battery even if hooked up to a powerful USB charger. Get a "dummy battery" for your camera.

> I tried using an old Nexus 4 as a live streaming camera a while back but after a few weeks the battery bulged and the gorgeous glass back shattered.

I hope you got rid of the phone or at least took out the battery, when it bulges it's having internal issues and now is a fire / explosion risk. You probably used a cheap power supply that has lots of high frequency ripple.

On many mirrorless cameras the shutter is open by default (even when the camera is closed), so not even one shutter "count" on this type of usage (the shutter is only used when taking a photo, and not even then if in silent mode is used). Shutter lifespans are in the tens of thousands to hundred of thousands normally. It's good to know the value when buying used (because you don't know what you are buying, some cameras have such a high burst rate that you can reach hundred of thousands in hours if you keep the button pressed).

For many cameras you can find a power line adapter that replaces the actual battery and connects to power (Canon cameras cannot charge their batteries in-camera so this is a must for them).

I don't think modern cameras are going to open/close the shutter continuously. That would cause a lot of noise while filming, and they usually record sound too. They rather use "electronic shutter" while filming, which is just another name for ignoring some exposure time. So it would count as one click, or maybe less.

> can you completely avoid using a battery with a power line adapter?

This is going to depend on the particular camera. I just tested a mirrorless camera, doesn't work without a battery, and doesn't use the DC power while on.

The shutter count is just a good estimate for how much the camera has been used.

Using the camera for video doesn't really have much impact compared to photography since the shutter is just kept open

In all cameras that have a video mode, the mechanical shutter does not activate on every frame. The exception is some video cameras that use a rotating mechanical shutter, but those do not have a limited number of clicks.

What is the advantage of a mirrorless camera in the webcam use case ?

it's truly a shame we can't get clean/raw video out of a modern smart phone.

They would mount easily, are accessible to the majority of people and are so incredibly superior to USB-Webcams (or those which are built-in to laptops, which also use USB internally).

I've seen some attempts at this but mostly they were focused on turning a phone into an IP Camera for monitoring, which had high latency, low quality and incredibly low frame-rates.

I use https://obs.camera/ with my iPhone 11 for lessons with my music teacher and it works great. Paired with the virtual video out feature of OBS it’s really easy to use with zoom as well.

Another option is https://www.elgato.com/en/epoccam but I haven’t used it much. Their software feels very janky compared to OBS Camera but I know it works (my teacher uses it in his end for our lessons)

Reincubate Camo works incredibly well. Bit expensive.

https://reincubate.com/camo/

I've been using it for two months now, I'm a happy customer. I made a cardboard cradle for my phone and velcroed it to the back of my monitor, works fine.

do you have a picture or drawing of your setup?

Hah, sure, here's the highly technical cradle: https://i.imgur.com/VRj5Fxs.jpg

It's a piece of cardboard bent to the size of my phone, wrapped with duct tape. Then a piece of velcro attached to the cradle, and the back of the monitor so that it pokes out up above.

I've seen pretty good video from the NDI Tools (https://www.ndi.tv/tools/), which includes a pair of smartphone apps (one to transmit the camera, a second to transmit a screen capture), and a receiver program on the computer that can feed OBS or Zoom. From what I can tell, NDI is video codec intended for use in broadcast studios (high-quality, high-bandwidth, some compression but not a lot, UDP, assumes a local non-lossy network), and there's a batch of tools around it to emit/accept those streams: mixing decks, monitors, routers, etc. Resolution and frame rate seem excellent, latency feels to be about 1.0 seconds.

Bonus points: it's made by NewTek, the original Amiga Video Toaster folks.

> it's truly a shame we can't get clean/raw video out of a modern smart phone.

https://petapixel.com/2020/09/09/filmic-pro-update-adds-clea...

Have you looked at ManyCam? I remember it being a very nice piece of technology that can switch between multiple cellphone feeds with effects while emulating a webcam.

Shameless self promotion: I create a from scratch implementation of a USB-MJPEG streaming server meant to run on low cost hardware. $10 USB web cam + a Raspberry Pi gets you a very simple nanny cam or similar.

https://github.com/ipartola/hawkeye

Hey Igor, just spent the last hour going through this repo.

Looks awesome. I built something similar but in Python/flask. This seems like it would be much faster. Thanks for sharing.

Of course! It was a pleasure to build. If you ever want to contribute to this project, let me know and I’ll add you as a contributor.

If anyone does this but finds their camera turns off after 30 minutes (and if you can't fix it by updating the firmware or changing settings), try this:

connect your camera via hdmi AND usb, then:

> brew install gphoto2

> gphoto2 --summary

You'll know it worked if you see your camera make/model show up.

That one --summary call is all that's needed for my Canon m50 to stay awake forever! I'm not sure if it works for other models, but when I figured that out I was super happy :)

Well, also instead of overheating your nice new DSLR, you can buy a perfectly good several-generation-old used one off CL/Ebay or somewhere for probably $75. For video streaming the technology hasn't changed much, and you're not going to be needing or exploiting cutting-edge resolution for these purposes.

Before anyone runs out and does this, it's not really going to improve much. The most important thing is lighting and once you have good lighting the difference in camera quality is pretty negligible for webconferences.

Good lighting is easier to achieve when your camera isn't a 1/4" pinhole.

Is there anything similar for IP Cameras? These often have IR LEDs/Night Vision, which webcams usually don't. But they tend to require really crappy software (Foscam, I'm looking at you).

If you're using linux, uv4l-mjpegstream will turn an IP camera into a /dev/video device that can be used by other applications.

https://www.linux-projects.org/documentation/uv4l-mjpegstrea...

For your Foscam camera this page should help you find the URI for the mjpeg stream: https://www.foscam.com/faqs/view.html?id=128

Thanks, that's very useful!

There's this project [0] which turns a Raspberry Pi into a USB webcam. It works with the RPi IR camera.

[0] https://github.com/geerlingguy/pi-webcam

Title should be "Turn any camera into a webcam with a $13 USB/HDMI video CAPTURE card".

1080p YUV2 at 5 fps ? No, thanks...

You're not going to be doing screen captures from a "webcam" and unless you're recording very fine line drawing MJPEG recording will look just fine.

If you're doing screen captures you're better off either capturing natively on the device. But if you absolutely need to use an HDMI dongle and need good quality screen recording you're better off getting a higher end dongle.

For less than $20 getting 1080p MJPEG at 30fps from an HDMI source is pretty good. The camera itself is likely recording video to MJPEG at its best quality settings and h.264 otherwise.

Can this be used to use your laptop screen as a monitor for a video game console?

You can use it but the cheap dongles (like this one) have about a 2/3 second delay. Even the best capture dongles have a 1/4 second delay.

They're useful for capturing gameplay to stream but not to use as a monitor.

$13 with amazon affiliate link from this blogspam, or $5 from ebay directly

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