Only 4 days of playback!

[faiz_syd]

I have a 4TB HDD in my Dahua NVR, and I am using five 4K cameras that record 24/7 at a bitrate of 5 Mbps each. However, I'm only getting four days of playback, which is not what I expected. My installer either miscalculated the storage requirements, as I was supposed to receive at least two weeks of recording, or I need to further fine-tune the settings.

I've also noticed that Smart Motion Detection (SMD) and Tripwire events work very well. How can I increase the number of playback days? If this limitation is due to my current setup, would it be better to change the recording schedule to motion detection and intelligent events, or should I consider upgrading to a larger hard drive?

 

[Revo2Maxx]

So there are a few things you can do.. First, I would double check that your NVR isn't setup for full time snapshots.. If it is that will also eat up your HDD space.. First thing I do is turn off all full time Recording for Snapshot and recordings.. Then if I need full time recording I will turn on the Sub Channel and this will give me full time recording just reduced quality but I can see and compare the events that are done in Main.. If that is something that interests you. Got to WebUI or GUI, Storage, Record and any channel that you want to record full time and are ok with Sub Channel quality then where the sub channel change that from Off to Manual. That will start recording your camera on the Sub Channel.. Then when you want to play back Just go to search or Playback depending on the model/year and firmware.. Then pick the channel you want to play back you will notice only events that recorded are on right now that is because it is setup for Main on the right click the M and change that to S and doing so will show the full time recording line.. For me I have mine setup this way in case an event that happens I can go and look to see if I can pick up any audio before the event happened. You know someone talking with their friends outside the IVS event area or around a corner and can hear audio but can't see anyone yet kind of thing..

So changing the Full time Recording on Main Channel to off.. That will help a lot, However on the few cameras you have to have full time recording use Sub channel. Removing all scheduled snapshots from full time to Motion, Alarm, and IVS will stop your system from recording an image every second on every channel.. That is 86,400 images per camera and a total of 432,000 for 5 cameras.. That is a lot of space being wasted..

 

[Revo2Maxx]

So here is a few pictures of how I have my recorders setup. Now on the Record page different recorders will have different channels setup for full time recording just showing this one to get an idea of what I am talking about.. Next I reset the 1 recorder back to factory and the picture of full time Recording and Snapshot was only thing enabled.. Then the one with IVS, Motion, Alarm setup is how I have all my recorders setup and control the full time recordings using the Record page by changing to manual.. The playback menu you can see on the right that the one with full time Green line is with S next to the cameras name.. The other is M and showing the events that happened...

 

[faiz_syd]

Thank you so much for the detailed explanation and screenshots. That's exactly what I wanted to do but couldn't work this out on my own.

 

[alastairstevenson]

If that is something that interests you. Got to WebUI or GUI, Storage, Record and any channel that you want to record full time and are ok with Sub Channel quality then where the sub channel change that from Off to Manual.

Maybe I've misunderstood what you're advising but I don't understand why you'd want to install 4k cameras and only record the substream when all that's needed is to size the HDDs to match the needed history.
The whole purpose of the installation is to be able to see enough detail to recognise or identify who and what has happened. Recording the substream only will severely compromise that.

I have a 4TB HDD in my Dahua NVR, and I am using five 4K cameras that record 24/7 at a bitrate of 5 Mbps each.

This should certainly give you 14 days or so recording history -
5*5*3600*24/8/1024 which is about 250GB / day
So there is something more than just recording 5 cameras at 5Mbps each going on.
Inadvertently having a snapshot schedule could be the cause.
At around 3MB per snapshot per camera once every 10 seconds would use about the same storage as the continuous recording.

 

[bigredfish]

^^^^
This. Why buy good cameras and record crappy video?

 

[Revo2Maxx]

Your right, having quality events recorded is important and with your DVR/NVR setup correctly you will get just that. But to record full time in main is a waste of hard drive space. So recording in Sub channel will give most users best playback experience with no break in video playback. For instance people with motion only recordings do a search for motion events however all other would be removed, then turning off motion in event to only play full time recording this will cause gaps in spaces where motion took place so recording as I have said they will have all events in main full sized and all full time recordings in sub channel will give all things that might have been missed. This can also help recover any leading audio to an event. But for let's say a camera that gets 20 events a day and all other video capture is same Ole static picture of what is seen might as well capture reduced video rather then waste hdd space. I mean if going to record full time on main then what's the use of setting up motion or having quality cameras that by using IVS/VCA to keep down false alerts. Just record full time main nothing else matters. Why not offer full option where someone has the ability to record in not only main but in sub as most don't even know this was an option. But I have been recording footage long before HD or ip was a thing so sub channel today is large upgrade from footage recorded in the 80s and 90s. But still enough for most historical record.

 

[faiz_syd]

Maybe I've misunderstood what you're advising but I don't understand why you'd want to install 4k cameras and only record the substream when all that's needed is to size the HDDs to match the needed history.
The whole purpose of the installation is to be able to see enough detail to recognise or identify who and what has happened. Recording the substream only will severely compromise that.



This should certainly give you 14 days or so recording history -
5*5*3600*24/8/1024 which is about 250GB / day
So there is something more than just recording 5 cameras at 5Mbps each going on.
Inadvertently having a snapshot schedule could be the cause.
At around 3MB per snapshot per camera once every 10 seconds would use about the same storage as the continuous recording.

I calculated as well and was expecting to easily get 12+ days. Snapshots were already disabled in the schedule.

 

[Revo2Maxx]

Under normal recording with 5Mbps full time should be over 14 days at h.265 and about 9.8 so say 10 days at h.264. The main issue is that every second of the day with default settings these recorder is taking a snapshot. Most times people don't even know they are there taking up space.. Or even how to access them lol.... Only way that it would be changed from 1 every second is if someone made that change in the recorder as by default they record 1 a second.. So doing the math on that.. Total Data/Day=86.4GB/dayX5=432GB/day this is with the idea of what my 8mp camera normal record the snapshot as 1mb per second for each of the 5 cameras that takes some major space in short order.. These images can go up and down depending on many factors as well so the numbers are just a rough estimate.. Just trying to be helpful.. Get the most for what they already have.. One of the many reasons I like my DVRs as I can pick the size of snapshots that are saved not just Full sized.. This makes it easier for cameras that don't require full image I can reduce the image size.. NVR is set size to Main channel image format only unless the NVR is using DVR channels as the cameras..

 

[bigredfish]

I never advocate recording ONLY MD/IVS or "event only"

I record everything - main, sub, snapshot and use IVS extensively to allow me to pinpoint events in areas I've defined.
HOWEVER, I would miss a LOT of stuff that is outside of my defined area and target type if I just recorded on event.
10 cameras, all 4MP 5442 series and 3 of the 4K-X/T
I run 30fps and 10240 on the 5442's and 30fps and 16384 on the 4K's



My theory is HD space is cheap. Don;t scrimp on quality or quantity for lack of HD space.

I use 5 sec intervals on scheduled snapshots and 1 sec on events

 

[Revo2Maxx]

If you are recording full time on Main why are you recording full time on Sub as well?