Camera Question 4k @30fps

EDIT: We may have found a solution tapping into our Racing Drone Community. Looks like we may be able to use a 4k FPV camera/DVR and communicate with it through a RaspPi interface.

We have a friend who wants us to help develop a system that will allow them to video an entire soccer field. Does anyone have a recommendation on where we can source usb cameras capable of this? We are wanting to create a single case that can be mounted on a tri pod that will see the entire field using two cameras. We hope to set it up to then stream the video to a server in real time that converts the two feeds into one video.

Okay so, let’s break this down a bit. There are high resolution USB camera sensors packaged for this type of thing on vendors like AliExpress that work fairly well. That said, they generally either are: high framerate low resolution, high resolution low framerate, or both and monochrome. None are particularly cheap.

Real-time camera stitching can be computationally intensive. Even beyond that, are you intending to manipulate the video stream in real-time (live-events), record it for post-production, etc? This all effects the scope and design.

Beyond that, most modern “USB cameras” have no moving parts, making everything simultaneously in focus, whereas more traditional cameras will have depth produced through variable focus lenses. And to boot, “modern” cameras are rolling shutter generally, so things like artifacts from strobes will be apparent.

I hope this at least helps point you in the direction of asking the right questions :slight_smile:

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If you do end up going down the “stitch images in real time” path, 2481 did a “top-down” view with four cameras a few years back and published the code. you might want to look into that for stitching the images together in a visually-meaningful way, though the geometry would be different.

Granted, this also may be overkill - simply merging the two frames side-by-side might get the job done, if you are very careful about how you position the two cameras relative to each other.

Can’t say I have much of recommendations other than that unfortunately. 4k cameras and processing doesn’t show up much on robots, and I don’t know much more than robots.

FYI, if you are trying to run this over any sort of distance greater than a few feet, consider not using USB. We trialed it for FTC and the only extenders we could find that are long enough are finicky and like to randomly require being unplugged and plugged back in, in addition to the limitations of running video over USB 2.0. Ethernet is a much better solution for midrange distances, if it’s very long distance I would suggest you look at SDI with a DeckLink handling input.

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Is this for surveillance or for livestreaming?

If its the latter, id be looking away from USB cameras and more into the realm of actual DSLR/Camcorders, especially if the cameras are going to be a fair distance away.

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100% unless it is a high end USB camera (talking professional/better than a C920) these are not made for the types of shots you are asking for and will look washed out and have a very poor depth of field. Not sure what your budget is but investing a couple camcorders with a capture card may be the way to go here. I’ve done 100FT HDMI runs for Ri3D and this is the setup we use. A lower end setup would cost you about $500-$700 and you may be able to find quiet a few used camcorders.

I would not recommend a DSLR here. Most DSLR’s have an auto shutoff of 30 minutes. Some programs like SparkoCam will auto close/open the shutter every 29 minutes to prevent issues but a camcorder would still be the way I go.

If not live: Then you can find lower end 4k camcorders and/or gopro’s for a pretty reasonable pricepoint.

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The stitching will not be live. We plan to record it, send it to a server, and then produce the final video for later analysis and training purposes. The final video product will be in 1080p, we need to 4k recordings to allow the software to do its thing.

The video will not be streamed live if that is what you are asking.

We use a system to analyse diver’s movements in post-production and have no issue with various cameras but they tend to be larger in size and looking at a smaller area. For what they need, they are looking for clarity over a larger field of view.

We suggested that, however their goal is to have as high a quality as possible while keeping a small form factor.

I used to do live webcast of major spring board diving events such as the USA Senior Nationals and the FINA Grand Prix events. We used video cameras feeding back to the video board over firewire back then. It worked great but the set up too lots of time and the investment was not small.

The end goal is to have a low cost, light weight, extremely portable option for parents who wish to hit record and forget about it so they can enjoy their kids event. After talking about this idea with my friend it could easily be used at FRC events by saving the files to sd cards and uploading post event.

Then 2 go pro’s would get the job done here or an off-brand one. I have seen many for <$100 for off-brand.

Example:
https://www.amazon.com/AKASO-EK7000-Sports-Waterproof-Camcorder/dp/B01HGM33HG/

Distance, as envisioned, will not be an issue as the entire package is planned to be self contained. Think of it as a Limelight camera that is self contained storing to a SD card locally or streaming to a cloud storage device when WiFi is available.

This would also be my suggestion. Many FRC events used this for livestreams back during the mid-2010’s, and i bet a few offseasons still do. Somewhere theres a doc for livestreaming an event with a single goPro, i can dig around and see if it exists still.

GoPro’s have fish eye lenses and the post production programming to flatten the video is intensive. We suggested that option as well.

To follow up as a resource: Here is FIRST’s official Live Video Streaming Policy

Fair warning - some bootleg GoPros may have something overlayed on the HDMI output. I have one that mirrors the camera’s whole screen on the HDMI output, including the “1080p video” indicator.

What we think they are trying to mimic

We were asked if we could figure out how to sync two 4k cameras together to capture an entire soccer field. Through the power of duckduckgo.com the above site came up as we searched for idea cameras.

That camera alone is $1500 looking at this article. Trying to replicate this on what sounds like a shoestring budget is asking for a lot honestly. The big reason im pushing for non-USB cameras is because i dont know any that would give both 4k video and the quality you’d need for this, and the ones id listen to on USB cameras who have responded so far dont know of any either.

Annoyingly, Veo seems to be very tight lipped on their camera specs, so trying to find a camera that can replicate what they have is more difficult that expected.

There are several GoPro models that can do this; you just need to capture an HDMI output instead of a USB output.

In general, if you get an HDMI capture card or two, you have many more options available to you.

Not sure the budget is shoestring , although it is not unlimited. I spoke to my friend about the Veo system just now and he said he actually has and is using that system. He is on this mission now because he feels like after spending $1500 on the camera, he should be able to have the video it records without having to pay monthly to access it.