Bit Rate

[AngieTexas]

Is it best to use the highest bit rate setting, if video live/record are stable?

Is CBR better than VBR?

Is it better to use a slightly lower bit rate for multiple streams, network traffic?

How do I determine the best bit rate?

Thanks

[Revo2Maxx]

Them are some Great Questions and they are kind of Complex...

CBR is Constant bit Rate
VBR is Variable bit Rate

So between the 2 the VBR is most times used for best Quality Videos over HTTP and it used to be said and I don't know if it is still true or not but CBR was CONSTANT and that means even if the data that has changed in a Frame isn't enough to cover the amount of Bits made the rest is lost in JUNK data... Now that might be on old tech and things might be different in some degree...

So with that said.. If your system is set to 4096 and the info changed inside the video was only 2048 worth then the rest of the data is junk not that it will harm your video just use up space on your Recorder...

So with VBR it would only move the 2048 of data and save space...

What is bits? Well Bitrate is the measure of data or the amount there of that is moved from point A to B in a given time... This is in 1's and 0's like 1001010111100 kind of format and that was just random meaning nothing to decode lol... anyway this is done in seconds hence the bps bits per second.

So for our cameras we are moving this data from the camera to the NVR or Computer software...

So for best quality video we need to give the camera some room, we need to increase resolution, frame rate and decreasing compression. with this Video Quality increases but also increases the need for more data traffic...

What has an affect in bitrate, Resolution, Higher Res More bitrate, Higher FPS Higher bitrate, Higher Compression Lower bitrate

I have more that I could type but sadly I have a Sick Pup and he is in need of my attention and I will try and add more to this later on.. I just hope he gets over this soon...

[AngieTexas]

HiYa James,

I hope the puppy is doing better, prayers are with you and the pup!!!

Main Stream:
So, if my resolution is 3840*2160
And my FPS is 30
What should my variable bit rate?

____________________________________

Sub Stream:
So, if my resolution is 704*480
And my FPS is 30
What should my variable bit rate?

Thanks

[Revo2Maxx]

Well to be honest it is going to depend on a lot of different factors in General...

However for you to be honest I would set your 2 most important cameras or however many your system can handle and try to set them at the Max that it can be set at...

Now for my system I have the ability to change another value and this is going to make things little harder for the system to render all things perfect but for ones that I want perfect or High Quality I set the Quality to 6(Best) as it is listed on my machine... Might be different on yours...

However when you set your system to VBR for your Encoding you will see a little area below that will show from XXXX-XXXXKb/S and should or could say Reference Bit Rate... So even for my 3mp and my 1080p camera it says same options for the NVR I am looking at this moment and is 1280-8192Kb/S However if I lower other parts of the settings area you should see only the first number go down... Like when I changed from 20FPS to 15 the first number dropped to 8xx something... Anyway that is MIN and Higher the number the larger the files it will record less time on your recorder.. So if you were getting 2 weeks on your HDD and start changing numbers to large values the good news is seeing your under VBR if set before under CBR you still might get the 2 or more weeks out of it because it is no longer recording junk info not needed...

Just remember that 1 Snap shot on my 4k camera at 4k was 33megs for a still picture

[Revo2Maxx]

Well did some testing on my 2116hs and tested at 3840x2160 QFHD
VBR
Quality 6
16384 Kb/S
Min was 4096 to 16384Kb/S so ran max and was no ghosting on this NVR over my 4108 in fact this one works better then WebUI

20200603_222432_resized.jpg (1.31 MiB) Viewed 4849 times

[AngieTexas]

You bit rate goes twice as high as mine, my max is 8192.
Is that because I am using h.265 instead of h.264h?

Also, why do you use CBR for sub stream?

Thanks,

[Revo2Maxx]

I changed only main encoding I also didnt have sub 1 or 2 recording.

I am going to guess that you running h265 was why because in yours only need half the Rate