OBS 25, W10: More than one webcam on HUB, not working.

[Tormy]

Not clue if this is normal, however, on a portable PC, I installed an USB3.2 hub on a USB 3.2 port.
Up there, I put 4 webcams.
Those cams, are viewed by W10.
OBS detects them properly, but when I go to select them as Video Capture Device, only one is showing the picture.
The other ones are returning black video.

Is that normal?

 

[Lawrence_SoCal]

Query overloaded USB hub.... many references in these forums.
Short answer - your result is not surprising at all
Also, realize USB 3.2 is too vague to be really useful (stupid USB forum/marketing fools) .... that could be 3.0 speed of 5gb/s, 3.1 speed of 10 gb/s, or 3.2 (Gen 2 2x2) speed of 20gb/s. And you laptop vendor's parts choice means the USB controller may or may not handle high I/O well.... it depends :(.... in your case, you'll obviously need to move one or more cameras to other ports? or do you have Thunderbolt 3 and a TB3 hub?

 

[Tormy]

Query overloaded USB hub.... many references in these forums.
Short answer - your result is not surprising at all
Also, realize USB 3.2 is too vague to be really useful (stupid USB forum/marketing fools) .... that could be 3.0 speed of 5gb/s, 3.1 speed of 10 gb/s, or 3.2 (Gen 2 2x2) speed of 20gb/s. And you laptop vendor's parts choice means the USB controller may or may not handle high I/O well.... it depends :(.... in your case, you'll obviously need to move one or more cameras to other ports? or do you have Thunderbolt 3 and a TB3 hub?

I have a PC Laptop, not any MAC thus no thunderbolt ports at all.
Yes, I have to move the cameras on separate ports.
Ridiculously I can use the inner camera, the 2 ones on the only 2 ports I have and then use as camera the iPAD , a Samsung Tablet and my iPhone, all via NDI, without any issue.
As soon as I want just more USB cameras ('cause I don't want to use my tablets or iPhone because they are overheating), connecting them to my Hub, it works only the first connected camera. All the other ones are off.

so, following what you say, it's a bandwidth issue of my Hub. Which feature should I check in a Hub, to be able to buy one that's capable to receive multiple Webcam please? Is the MTT parameter? Or is ti something else?
Is the all day I'm looking for a precise answer.

Thank you in advance

 

[Lawrence_SoCal]

I have a PC Laptop, not any MAC thus no thunderbolt ports at all.

Uh .. no... In my household are 4 Win10 laptops all with Thunderbolt 3 (1 gaming machine, 2 business class laptops, and 1 workstation level). So Intel CPU laptop with Thunderbolt 3 is NOT uncommon (just not on low end consumer gear, which I avoid like the plague)

Yes, I have to move the cameras on separate ports.
Ridiculously I can use the inner camera, the 2 ones on the only 2 ports I have and then use as camera the iPAD , a Samsung Tablet and my iPhone, all via NDI, without any issue.

I understand the frustration, but no, not ridiculous at all. NDI traffic coming in over Ethernet port (hopefully) or maybe WiFi, whole different chip than USB hub. The scenario you have above has the video traffic spread out, not causing a bottleneck.

As soon as I want just more USB cameras ('cause I don't want to use my tablets or iPhone because they are overheating), connecting them to my Hub, it works only the first connected camera. All the other ones are off.

Though convenient, what you are doing is creating a bottleneck. Further, the USB hub is part of the motherboard, and depends on make, model, etc. Usually it is part of the required chipset that goes with the CPU. To change it means new laptop motherboard, which in your case means new machine. (on a desktop you could add a new PCIe card and add a new I/O port /interface/hub. Some vendor models have higher quality, better designed interfaces. But you are seeking details when you haven't posted exactly what you have (make, model, CPU, etc). And it really doesn't matter. You aren't going to change the USB I/O hub. and you've already confirmed the problem. Higher end laptops, depending on design (ie not slim/lightweight models) may have separate USB hub(s) which would overcome your challenge. You'd need to do your homework when selecting a new machine

Also, if you do a search the other issue you'll find is that the drivers for many webcams are VERY poorly written. Sometimes, using different webcams (so driver itself isn't the bottleneck) might help (or make things worse... it depends). If you are in a position to use/test higher quality webcam and drivers, that might help (or not). Lowering the bandwidth (in this case, resolution) of the webcam, might help (or it could be a resource contention issue outside of bandwidth).

I know you want a precise answer, and if it was easy, I'd love to be able to provide such for you. but that isn't the case this time. You are asking about something that is technically challenging (CPU, chipset, motherboard design, OS & driver issues, etc), so I hope I've pointed you in the right direction.
I've read reference in these forums to some testing tools out there for monitoring the USB hub. I'm not sure if such might help you

Good luck

 

[Tormy]

Uh .. no... In my household are 4 Win10 laptops all with Thunderbolt 3 (1 gaming machine, 2 business class laptops, and 1 workstation level). So Intel CPU laptop with Thunderbolt 3 is NOT uncommon (just not on low end consumer gear, which I avoid like the plague)



I understand the frustration, but no, not ridiculous at all. NDI traffic coming in over Ethernet port (hopefully) or maybe WiFi, whole different chip than USB hub. The scenario you have above has the video traffic spread out, not causing a bottleneck.



Though convenient, what you are doing is creating a bottleneck. Further, the USB hub is part of the motherboard, and depends on make, model, etc. Usually it is part of the required chipset that goes with the CPU. To change it means new laptop motherboard, which in your case means new machine. (on a desktop you could add a new PCIe card and add a new I/O port /interface/hub. Some vendor models have higher quality, better designed interfaces. But you are seeking details when you haven't posted exactly what you have (make, model, CPU, etc). And it really doesn't matter. You aren't going to change the USB I/O hub. and you've already confirmed the problem. Higher end laptops, depending on design (ie not slim/lightweight models) may have separate USB hub(s) which would overcome your challenge. You'd need to do your homework when selecting a new machine

Also, if you do a search the other issue you'll find is that the drivers for many webcams are VERY poorly written. Sometimes, using different webcams (so driver itself isn't the bottleneck) might help (or make things worse... it depends). If you are in a position to use/test higher quality webcam and drivers, that might help (or not). Lowering the bandwidth (in this case, resolution) of the webcam, might help (or it could be a resource contention issue outside of bandwidth).

I know you want a precise answer, and if it was easy, I'd love to be able to provide such for you. but that isn't the case this time. You are asking about something that is technically challenging (CPU, chipset, motherboard design, OS & driver issues, etc), so I hope I've pointed you in the right direction.
I've read reference in these forums to some testing tools out there for monitoring the USB hub. I'm not sure if such might help you

Good luck

Well, I have not clue how to use "better written drivers" for webcams that come with their ones. I cant' change or improve them :-/
I was wondering if I could use an external HUB compatible MTT could support multiwebcam avoiding to buy a new computer, being what I do now, at experimental level.

 

[Tormy]

Uh .. no... In my household are 4 Win10 laptops all with Thunderbolt 3 (1 gaming machine, 2 business class laptops, and 1 workstation level). So Intel CPU laptop with Thunderbolt 3 is NOT uncommon (just not on low end consumer gear, which I avoid like the plague)



I understand the frustration, but no, not ridiculous at all. NDI traffic coming in over Ethernet port (hopefully) or maybe WiFi, whole different chip than USB hub. The scenario you have above has the video traffic spread out, not causing a bottleneck.



Though convenient, what you are doing is creating a bottleneck. Further, the USB hub is part of the motherboard, and depends on make, model, etc. Usually it is part of the required chipset that goes with the CPU. To change it means new laptop motherboard, which in your case means new machine. (on a desktop you could add a new PCIe card and add a new I/O port /interface/hub. Some vendor models have higher quality, better designed interfaces. But you are seeking details when you haven't posted exactly what you have (make, model, CPU, etc). And it really doesn't matter. You aren't going to change the USB I/O hub. and you've already confirmed the problem. Higher end laptops, depending on design (ie not slim/lightweight models) may have separate USB hub(s) which would overcome your challenge. You'd need to do your homework when selecting a new machine

Also, if you do a search the other issue you'll find is that the drivers for many webcams are VERY poorly written. Sometimes, using different webcams (so driver itself isn't the bottleneck) might help (or make things worse... it depends). If you are in a position to use/test higher quality webcam and drivers, that might help (or not). Lowering the bandwidth (in this case, resolution) of the webcam, might help (or it could be a resource contention issue outside of bandwidth).

I know you want a precise answer, and if it was easy, I'd love to be able to provide such for you. but that isn't the case this time. You are asking about something that is technically challenging (CPU, chipset, motherboard design, OS & driver issues, etc), so I hope I've pointed you in the right direction.
I've read reference in these forums to some testing tools out there for monitoring the USB hub. I'm not sure if such might help you

Good luck

let me ask, please, aslo:

what about to interface each camera with an USB-to-Ethernet adapter, going to a Switch, then to the Laptop (having an Ethernet port up there)?
In theory I should see each camera through NDI. Do I wrong?
And if it's so, it should be correctly managed.

What do you think?

 

[Lawrence_SoCal]

what about to interface each camera with an USB-to-Ethernet adapter, going to a Switch, then to the Laptop (having an Ethernet port up there)?

I've never used a USB-to-Ethernet adapter, so can't be sure.
Other such adapters use Ethernet as transport (to get distance), but aren't converting the data, which means you need to convert back to native protocol (USB in this case, HDMI, KVM, etc) at other end. *if* that is what you are looking at it won't help you at all. Typically a computer/CPU is required to convert USB into other data stream... and adding a Raspberry Pie or similar seems like overkill, and fragile. I'd be more inclined to see if a 'smart' USB switch (vs 'dumb' hub) might help... I have no idea if such thing even exists, or would apply in this scenario. I'll leave that to you to research

As OBS specific USB I/O hub constraints is something I've read about in these forums, but not directly had to address, I'll let others (far more knowledgeable than I, address any further questions on this, or advise on overcoming the limit you have encountered .
I do recommend searching this forum on USB hub for other conversations/advise on your issue