Substreams and setting quality based on number of cameras being viewed live?

[justinneed]

First question is: are there any quality NVRs that are able to stream multiple camera feeds at full 4K. I'm curious because I know of some Blue Iris setups I've seen online where I would imagine they are more powerful than a NVR, but they struggle to have multiple 4K streams and they rely on substreams, so I'm suspicious that any NVR out there is able to do multiple 4K streams. Most products out there don't mention anything about substreams/live stream quality vs what is actually being recorded. A lot of people I know assume the cameras they buy, especially the low quality stuff they get on Amazon or Costco will give them a live 4K feed of all 12 cameras they have, but I'm doubtful of that. At the very least can NVRs be adjusted so that 4 streams can be viewed at higher quality vs 10 streams and so on and so forth. Is this something that can also be done with Blue Iris?

We currently have an old super outdated DVR, but it's dumb enough that people here can just press a button and it will toggle between different number of streams (single, 4, 8, 12, 16). Since the feed is pretty low resolution, it can stream everything just fine, but I'm aware this isn't the case when you start moving up in resolution unless you have a very high end CPU.

Say I wanted something similar, but with substream setup in place to adjust based on the # of concurrent feeds being viewed so that the system doesn't get overloaded (assuming it's just not capable of viewing 10+ cameras at 4MP or higher at the same time), are most NVRs, including Blue Iris, capable of doing this automatically, so that when the user selects a single feed it'll show the full 4k resolution, then goes down to say 4MP at 4 stream, then 1080p at 12, or whatever the machine is capable of doing?

I'd like something to be setup like this because we don't really need high resolution when viewing all the cameras at the same time on the screen, but say someone notices suspicious activity on camera 5, I'd like the person to be able to toggle the single view of that specific camera and get the highest resolution possible. I'd also like it so that the user doesn't have to go and manually set a higher resolution just for that specific case.

 

[wittaj]

Substreams for multi-camera viewing was a thing in NVRs before it came to BI. The processing power of trying to display multiple high MP cams isn't really worth it. A high bitrate substream is more than adequate.

When you solo a camera in an NVR or BI it will show mainstream provided the NVR is capable of that MP. And when you go back to multiview it goes back to substream.

 

[AP514]

@wittaj - Is that why with only 1 cam I am showing -- -- for my Substream in BI ? (General-on the Cam settings)

 

[Mike A.]

That means that there isn't a substream or it's not working.

 

[AP514]

hum....Thanks for that info...I see substream when I go into the CAM but not in BI(under the Cam-general)

 

[Mike A.]

Do you see numbers for the substream in the cam listing under status (graph with an arrow at top left)?

If not, then check in camera settings > Video tab > configure that you have a substream configured there and that it's right.

 

[justinneed]

Substreams for multi-camera viewing was a thing in NVRs before it came to BI. The processing power of trying to display multiple high MP cams isn't really worth it. A high bitrate substream is more than adequate.

When you solo a camera in an NVR or BI it will show mainstream provided the NVR is capable of that MP. And when you go back to multiview it goes back to substream.

What kind of bitrate would you recommend for a sub stream? I understand this will depend on what I end up using.

I referred to the "Choosing Hardware for Blue Iris" and "Sub Stream Guide" posts. It looks like 12 cameras at 1080P at 15 FPS would be roughly 372 MP/s. Multiplying that by 10 would give me a CPU Mark score of 3720. Assuming I get an 8th gen i5 or better, I think 1080p @ 15 FPS would be feasible for me, but is there anything else I should take into consideration?

 

[wittaj]

The resolution you run for substreams comes down to your eyes and monitor you are using.

Some people claim they can see major differences between a mainstream and substream when 30 cameras are thrown up on a monitor LOL.

Personally, D1 at a higher bitrate looks great to me on multi-cam view - plus I use AI with BI for some of them and they are spot on. It is certainly enough for me to see what is going on and then solo a camera if I need to.

Take a look at this thread - even though it is for LPR, it shows that D1 with a high bitrate is more than sufficient for a 3rd party plate reader, so mult-cameras on a screen should be just fine also:

How much resolution is really needed for LPR

We have folks come here all the time thinking that more MP is better, whether it be for general purposes or for LPR. Those of us that have been around long enough know that sensor size is more important than MP. Those that have been here awhile know that I share a representative sample of...

ipcamtalk.com

 

[fenderman]

You would not be able to see a discernable difference in the live stream if you had multiple cameras displayed in a matrix. This is particularly true if you use the 2mp third stream available on many dahua cameras as the substream. Best of both worlds. This can be done in BI but I dont know about the dahua NVR.

 

[CCTVCam]

1080P @ 4,000KBS should give you a high quality sub stream if your NVR can manage it on multiple cameras on h264 / h264H, H265 (Latter can have issues not because of bit rate nut inherent issues to h265).

I can't see a huge difference between it and my 4k stream @ 16,800kbs!! Then again, I've often said, the compression ratio is a little high on the standard codec settings for these cameras in my opinion, although you won't notice it unless you try to zoom in on the picture.