IPC-Color4k-X Frame Rate Changes Between Night & Day

[TheOtherMike]

While looking into settings related to bit rate in this thread IPC-Color4K-X Bitrate and Synology I noticed that the frame rate from my IPC-Color-4k-X was ~8 fps despite being set at 15 fps.
Now a few days later, I've noticed a pattern in which the frame rate at night is 8 fps and then 15 during the day.

The camera is working great AFAIK, but I don't know much. Maybe it's a camera thing or maybe a Synology thing, although I don't have this issue with my two IPC-Color-4k-T cameras, so probably a camera (4k-X) thing.

Viewing stats of a night time recording using VLC shows the frame rate to be 8.33 fps with 43 dropped frames.
This is 2 minutes worth of playback stats:



A day time recording shows 15 fps and these VLC stats for 2 minutes - 0 dropped frames:




Original factory firmware:


Video settings for main stream:


I am using the "General" profile with Day & Night mode set to Color:


Exposure is "Auto"
Backlight is HLC=14
Illuminator is off

 

[bigredfish]

My first guess is H.265 is the culprit. Looks like bitrate drops at night.
Not a fan of Dahua's h.265 it doesnt seem to conserve that much and creates other issues. Try h.264 or h.264h

FWIW I run both of my 4K cams at 16384

 

[TheOtherMike]

Thanks for the tip. Are your 4ks "T"s or "X"s? My 4k-Ts are stable at 15 fps 24/7 although at only 8960 Kbps.

I set the 4k-X up as h.264 (15 fps, 8192 Kbps) and sometime after dark it went from 15 fps to 8 fps.

I just set it to h.264h and it stays at 8 fps (actual) but the web UI knocked the bit rate setting down to 6966 (or so).
I set the bit rate to 8192 in the web UI and the reported frame rate is 8 or 9 fps and the reported bit rate bounces between high 6k and high10k.

Setting the bit rate set to 6144 in both SS and web UI produces the same 8 or 9 fps and jumpy bit rate between low 4k and high 7k.

I see a new parameter in the web UI (SVC) - no idea what it is.



I set it to 2 & 3 (max value) - no better or worse.

 

[Timokreon]

What are you secondary stream settings?
Also, are you on PAL or NTSC?

 

[TheOtherMike]

NTSC
Sub 1 is disabled.



(yeah, I went back to h.265)

 

[TheOtherMike]

Sub stream is also coming in at 8 fps.

 

[wittaj]

I have seen cameras fluctuate FPS when they get inadequate power - perhaps at night you have other cameras on same switch going to infrared and taxing out the power supply?

 

[TheOtherMike]

I have seen cameras fluctuate FPS when they get inadequate power - perhaps at night you have other cameras on same switch going to infrared and taxing out the power supply?

Good call, but I have one of these

https://www.amazon.com/TRENDnet-Ethernet-Injector-Distances-TPE-115GI/dp/B00BK4W8TQ?ref_=ast_sto_dp&th=1

for each camera and I do not run IR or LEDs.

Is there an API I can call to get CPU load? Thinking/guessing maybe SSA-related functions may be taxed with very low light.
My 4k-Ts hold up in same lighting, but the X is much brighter and perhaps working harder.

 

[bigredfish]

I have one of each. While I see fluctuations live in SmartPSS which I use as a primary live view/playback tool, nothing like that. Mine all run off a Dahua PoE NVR.
One runs in a pitch black scene (T) and the X runs in a reasonably well lit scene with a street light…

Are you running Auto exposure and SSA 24/7? That could be part of it…. ? Seems like by design those two settings will produce wide fluctuation ..(as well as motion blur in low light)

I use the “Schedule” profile and manual shutter, no SSA

 

[wittaj]

Yeah if you are using SSA that will cause it.