Bitrate for 2MP with h265?

[rufunky]

Just wondering if maxing out my bitrate is necessary or is it overkill?

I have mine set at 6144 KB on constant bitrate (CBR) at 1080P with H265 encoding. I only have 4 2mp cameras and a 4tb drive so I have plenty of space but at the same time, I feel the more recording I have the better.

Thoughts?

 

[john-ipvm]

Why constant bit rate? Is that specific to your camera? In general, VBR works well on cameras, dynamically adjusting bit rate consumed to maintain quality level assigned.

6Mb/s is higher than average for what we see in testing various cameras but it depends on the frame rate, scene complexity, manufacturer being used, etc.

 

[rufunky]

Why constant bit rate? Is that specific to your camera? In general, VBR works well on cameras, dynamically adjusting bit rate consumed to maintain quality level assigned.

6Mb/s is higher than average for what we see in testing various cameras but it depends on the frame rate, scene complexity, manufacturer being used, etc.

I just assumed CBR was better, I am unsure of how VBR works. My scene is pretty static for the most part. By that I mean I do not live on a busy street therefore not a lot of fast cars going by, random door knockers etc. I have dahua IPC-HDW5231R-Z .

 

[john-ipvm]

VBR is generally better than CBR since CBR wastes bandwidth if set too high or degrades quality if set to low.
Our tutorial CBR vs VBR vs MBR - Surveillance Streaming

 

[rufunky]

VBR is generally better than CBR since CBR wastes bandwidth if set too high or degrades quality if set to low.
Our tutorial CBR vs VBR vs MBR - Surveillance Streaming

Thank you John, I'll check that out!

 

[rufunky]

Interesting read and demo video! On the dahua settings screenshot the Quality was covered but I assume "best" is what I should have it set at under VBR?

 

[john-ipvm]

Quality is ultimately a personal preference but, from our testing, 6 would likely be wasting bandwidth/storage relative to the visible quality gains it delivers. Manufacturers map the quality scale to a quantization scale for the compressor and we found 4 was already quite low relative to other manufacturers. See our test report unlocked here IP Camera Manufacturer Compression Comparison

 

[rufunky]

Got it, I just read through the IP Camera Manufacturer Compression Comparison report. Good stuff, a bit confusing do to the non-standardized quantization levels... But I get the gist of it