Confused on main/sub streams and CPU use

[cdogg44]

I have a W10 i5-6500 box running BI5. It's been rock solid for a year and I'm just now finding time to tweak settings and get things lined out.

Cameras are two EmpireTech 5442T-ZE. I am recording continuously for both cameras. So far so good.

I was digging through the menus and changed some settings today and my CPU usage has gone from <5% to ~18%.

What I did was turn off sub streams for both cameras and also deselected the "record dual streams if available". From my past footage it appeared my continuous recordings were in full quality so I'm not sure why having sub streams ON but not recording or being used would triple CPU usage. Any ideas?

 

[wittaj]

Because BI will use substreams for things that can be used for substreams as it relates to motion detection, multi camera views, alert images, etc.

If it uses mainstream for all of that, you get triple or more CPU usage depending on camera resolution and number of cameras.

 

[cdogg44]

Because BI will use substreams for things that can be used for substreams as it relates to motion detection, multi camera views, alert images, etc.

If it uses mainstream for all of that, you get triple or more CPU usage depending on camera resolution and number of cameras.

So I'm better off using sub streams, correct? And BI will only record the Main Stream which is full quality.

Thanks for the quick reply!

 

[wittaj]

Yes. If substreams resulted in inferior video of an incident, none of us would use it.

Keep in mind NVRs have used the substreams for years and BI was actually late to the game in implementing that feature.

There is no downside to substreams.

You can tell BI to record 24/7 mainstream or to save storage tell it to record continuous + triggers, which will record substream until triggered then go to mainstream during an event and then back to substream.

 

[cdogg44]

Yes. If substreams resulted in inferior video of an incident, none of us would use it.

Keep in mind NVRs have used the substreams for years and BI was actually late to the game in implementing that feature.

There is no downside to substreams.

You can tell BI to record 24/7 mainstream or to save storage tell it to record continuous + triggers, which will record substream until triggered then go to mainstream during an event and then back to substream.

Thank you. I am familiar with the idea of only recording the sub stream until a trigger but with only two cameras have the space to just continuously record. I did not take into account that sub streams were valuable if I was not using them for this purpose.

 

[bp2008]

Keep in mind NVRs have used the substreams for years and BI was actually late to the game in implementing that feature.

Very, very late. lol. But better late than never.

It was my biggest motivating factor for wanting to write my own NVR software, because I knew the crazy high CPU usage was not necessary. But fortunately I am very lazy so I just stuck with Blue Iris

 

[Flintstone61]

You can also drop your frame rates a little bit to reduce the %age of CPU usage.
You can also try enable/disable Hardware acceleration or no Hardware acceleration and see which one drops CPU usage or adversly affects the system.