Glitching / Pixels / Ghosting

[Robert G.]

I have a DS-7608NI-I2/8P, with 5 cameras.

It is set to record the main and sub streams to disk.

When watching in live view it is always smooth and looks fine.

When viewing playback of the main stream there can be pixelation, ghosting, objects vanish or are shown when they have already left (like after a car drives away it will continue to show).

Here is an example video, you can see a guy sitting on the steps. But he is all distorted and you really can't see what is going on. Some cops drive on the street, stop and talk to each other. Then POOF they are gone like Harry Potter made them vanish.

Frankly the video looks totally fake and altered, I could never show that video to someone they would think it is a fraud.


Now, if you watch the same video that is the sub stream it is perfect. The resolution is lower and the FPS is low but the video accurately represents what really occurred.


I am assuming the NVR is messing up when recording the video. Anyone shed any insight into what the issue is?

 

[alastairstevenson]

For the camera in the sample video:
What encoding is used?
What bitrate and fps is used?
What's the noise reduction setting?
How did you extract the clip?
Do you see the same when using Playback in the VGA.HDMI interface?

 

[Robert G.]

The encoding on the video is x265+. I have tried x265 (no plus) and the result is the same.

I have tried different FPS settings, everything from 10 - 20 FPS. When I enable the x265+ the Max Bitrate on the NVR GUI greys out and shows 8192 so I can't change that.

I have read on the forums of others with problems when jacking up the noise reduction too high, I don't even know how to alter that. I don't have access to the camera GUI, so whatever the default is would be what it is set on.

I have tried exporting the video clip from both Explorer (with plugin activated) and from iVMS-4200 Lite, both result in the exact same quality.

Unfortunately I don't have access to the local NVR to view it on the local monitor. I am thousands and thousands of miles away with the next site visit in April 2019.

The current test I am running is reducing the resolution. The max resolution of the camera is 3840*2160, I am dropping it down to 3072x1728 to see if that takes some stress of the camera.

 

[alastairstevenson]

I don't have access to the camera GUI, so whatever the default is would be what it is set on.

You should be able to do that via 'Virtual Host', the links in the right-hand column of Camera Management of the NVR web GUI.
The enable tickbox is under Network | Advanced settings | Other.

 

[Robert G.]

Yes, I have Virtual Host configured and I can access the login page of the cameras... but I have a password problem. Apparently I will be able to view/set the password but I must be physically at the console. Might be able to get someone to try and get the password via the console if I ask nice but not for a few weeks probably.

 

[alastairstevenson]

I knew about that - but had totally forgotten it. Apologies ...

 

[tangent]

It's interesting how the time stamp jumps around.

I have tried exporting the video clip from both Explorer (with plugin activated) and from iVMS-4200 Lite, both result in the exact same quality.

Unfortunately I don't have access to the local NVR to view it on the local monitor. I am thousands and thousands of miles away with the next site visit in April 2019.

So you're exporting the video remotely somehow. Are you exporting directly to your remote computer or exporting to a local computer that's on site and then copying it to the remote system? If it's the former try the latter.

 

[Robert G.]

@tangent , I do have a local computer on the same network as the NVR. The result of the export was the same.

I have been conducting a test for a few days to reduce the resolution of the main stream, down 1 level of resolution. That actually seems to have made a difference.

So that leads me to the questions, who is responsible for what?

The NVR is obviously responsible to save the footage. The camera takes the photos, both those steps are obvious.

If I select h265 encoding, who is doing the encoding of the footage? I'm guessing it is the individual cameras that encode at the requested resolution and stream that to the NVR. The NVR I'm guessing is literally just recording whatever the camera is sending it.

If the above is true I tend to put the blame on the camera.

There could be other factors, bad network cable, under powered network switch, hard drives in the NVR can't keep up with the write speed demand etc.

 

[tangent]

I would tend to think it's a problem with the NVR.

 

[Robert G.]

My test of lowering the resolution of the cameras seems to work well. No more glitching or issues. Now I guess I will bump the resolution back up and see if the problems come back.

 

[tangent]

The current test I am running is reducing the resolution. The max resolution of the camera is 3840*2160, I am dropping it down to 3072x1728 to see if that takes some stress of the camera.

That probably has a bigger impact on the NVR than the camera. The NVR can only handle so much bandwidth. Pay attention to the bit rate and the questions you were asked above:
Glitching / Pixels / Ghosting

 

[Robert G.]

The NVR is an 8 port unit. I was planning to use all 8 ports, only 5 are in use currently.

Sounds like it would be safer to purchase another 8 unit and split the cameras 4 on each.

 

[tangent]

The NVR is an 8 port unit. I was planning to use all 8 ports, only 5 are in use currently.

Sounds like it would be safer to purchase another 8 unit and split the cameras 4 on each.

That NVR has 80mbps of incoming bandwidth. In other words the total bitrate of all your cameras added together can't exceed 80mbps.