DS-2CD2686G2-IZS - 8MP varifocal - Bad 'Ghosting' video artefact

[ABCcam]

This has been discussed on various other posts regarding 8MP Acusense issues.
DS-2CD2686G2-IZS - 8MP varifocal has a bad ghosting issue which is most noticeable at night, although it occurs all the time.

If any objects moves then the image within the object does not move together with the edges of the object.

Firmware 5.7.10 220830 - latest available on HIKvision Africa site.
Have also tried 5.7.11 221009 from HIKvision Euro portal (thanks to IPcam forum help).

The artefact occurs for all camera resolutions (even downgrading to 1920X1080 does not remove the ghosting)

In the example vid below the spots & stripes in the Genet 'swim' giving the animal a ghosty and blurry look despite other stationary objects at similar depth being in focus.
When the platform shakes the wood pattern does not follow the movement of the edges.

Settings have been optimized as much as possible and assistance from HIKvision Africa support has not removed the ghosting issue.
Note: i use 4 & 5MP HIKvision cams and do not get this issue.

Options:
1 - New firmware? - does anyone know how to get HIKvision HQ attention to look into this?
- this is a stretch as based on forum posts this issue has been noted since 2020.
2 - Return cam and get a better cam without issue?
Any suggestions for an outdoor 8MP varifocal 2.8 - 12mm bullet - HIKvision or other?

 

[wittaj]

I think you are experiencing the issues of a 4K camera on a 1/1.8" sensor, which is the ideal sensor size for a 4MP camera.

At that tight of a field of view, the algorithm to give it a bright image is struggling and you are getting the halo effect that we see around motion sometimes.

Downrezing isn't going to do anything as it is still the same number of pixels spread over that sensor.

Unfortunately there isn't a varifocal 4k on the ideal 1/1.2" sensor on the market yet (at least economically).

But it could be your settings as well that could mitigate some of it.

 

[fenderman]

Post your video settings including any wdr and noise reduction

 

[ABCcam]

I think you are experiencing the issues of a 4K camera on a 1/1.8" sensor, which is the ideal sensor size for a 4MP camera.

This probably explains why this exact same artefact occurs on many cheap knock-off cams.
pity that HIKvision decided to create a cam with the same bad tech combination.
This issue basically kills any benefit of 8MP/4K where a lot of motion is expected and picture quality is extremely important.

 

[ABCcam]

Current 'generic' settings that work for day & night.
There are variations that can be subjectively considered better for day or night, but none remove the 'ghosting' / 'halo' effect



At night DNR is required to remove grainy picture.
For day the DNR can be turned off but does not remove the ghosting/halo

 

[fenderman]

This probably explains why this exact same artefact occurs on many cheap knock-off cams.
pity that HIKvision decided to create a cam with the same bad tech combination.
This issue basically kills any benefit of 8MP/4K where a lot of motion is expected and picture quality is extremely important.

This is not accurate. The 1/1.8 sensor is great for 8mp cameras. Cheap cameras do not use this expensive sensor. Smaller sensors were used prior to this sensor and the 1/1.8 produces a great surveillance footage if set correctly and used in the right environment. It is better in low light than many 2/4mp cameras from just a few years ago. Your wdr is set too high. Possibly also your noise reduction. Disable both and you will see the issue go away. It may also be related to your variable bit rate, set it to constant and test. My money is on the WDR. Another thing to note is your iframe interval is set to 5 yet your fps is 25. Set the iframe interval to match the FPS, at 25.

 

[ABCcam]

Thank you for your input.
DNR is off during day.

At night it has to be used to remove grainy picture.

WDR is necessary to handle the light variation.
Without WDR or HLC the picture is far too harsh with too many shadows / bright spots. Light also varies through day / season / weather - WDR or HLC is unavoidable.
Day: HLC gives a generally dark image, WDR is better despite the unavoidble 'whitewashing'
Night: WDR & HLC can be turned off but does not remove the ghosting/Halo


WDR

HLC

 

[ABCcam]

I agree as regards your recommendation on CBR & I Frame rate, although neither of these settings have any effect on the ghosting/Halo during day.
For streaming i prefer constant bit rate.
VBR & i Frame interval was set at 5 as recommended by HIKvision support to remove flicker at night.
During day it does not give noticeable difference if CBR, VBR, i-F 5, i-F 25 or i-F 50.
This was all done a few days back and not changed while other settings were adjusted so it probably is a good idea to revisit to make sure.

I have set it back on CBR and & I Frame 25 and will see what it does tonight.
Day: No noticeable difference as seen before although it is not a major issue in the day.

 

[ABCcam]

Settting at night:
DNR Off, WDR Off, HLC Off
Exposure 1/25, Gain 50
The ghosting/Halo does appear less.

Only problem is the old issue of flickering and freezing is back.

Exposure 1/3, Gain 40 - no flickering, but freezing still occurs.

Turning on DNR Normal 20 reduces freezing at expense of added blurring.
Still freezes with animal movement.
Wonderful Darkfighter low light performance - Not!

 

[dimammx]

Exposure 1/25 is a bit slow and will cause blur on moving objects. The freezing issue is very strange like at 16 secmark the whole frame is frozen. WHat are you using to capture and record the video ?
Also what is the light source, cheap led lights are notorious for flickering on video, generally keeping exposure to frequency of the grid helps, but based on design of the driver PWM frequency might not be

 

[ABCcam]

Exposure 1/25 is used as color day view is required.
1/50 or higher is too dark and/or requires too much gain which adds to noise.

Physically diffused LED flood lights are used (the lighting intensity is very low). Agreed that cheap LED's do have their issues of flicker and other weird colours.
These lights were chosen from tests with many different brands and have been working perfectly for more than two years with the 5MP Hikvision cam (see many other previous videos on YouTube channel).
Understood that it may not apply the same to the 8MP cam.

VLC capture on OBS is used - same as has and is being used for other cams. Have never seen this on other cams.

 

[Mike A.]

Maybe try setting the resolution for the 8MP cam to 5MP as a test and see if you get the same. If not, then maybe the buffer size in OBS needs to be increased to work with the higher bitrate.

 

[ABCcam]

Maybe try setting the resolution for the 8MP cam to 5MP as a test and see if you get the same. If not, then maybe the buffer size in OBS needs to be increased to work with the higher bitrate.

How do you change it from 8MP to 5MP?
The pixel frame extents can be changed but that does not change the fact that it is a 8MP sensor.
Why would one even want to do that? - buy a ferrari and run it at 20mph
As weird of an idea it may be i have already tried that - set the frame size to 1920x1080 to see if it helps - unfortunately makes no difference (@wittaj also posted that it would not change anything)

The buffer size on OBS has been adjusted the same and far higher than the cam max bitrate. All connections to cam are Gigabit adapters and fiber so there is no expectation of a network lag issue.
The freezing can be seen directly on the cam web interface live view or VLC rtsp stream view without any interaction with OBS

 

[tech_junkie]

I frame interval

Set it at 150 and slowly bring it down if it ties up too much bandwidth on the network.

Normally, when using a Hikvision NVR, set h.264+ to "on" for the NVR's encoding server to auto adjust this setting. When this setting is too low, too many sequential video frames are discarded.

2688 × 1520 (5mp) @30fps , main stream, all other substreams: 640 × 360
Constant bit rate is most of the time better than variable bit rate, but if you can't go into CBR, check your wiring for kinks or twists.

 

[tech_junkie]

How do you change it from 8MP to 5MP?
The pixel frame extents can be changed but that does not change the fact that it is a 8MP sensor.
Why would one even want to do that? - buy a ferrari and run it at 20mph

Because the user wants to run a non linear security ip camera like a real time analog camera. And you have to set up the camera's encoding server to output all frames in real time like an analog camera.
The resolution doesn't have to drop below 3200 × 1800, but I suggest 2688x1520 @30fps because I known from experience the camera runs cooler.

 

[alastairstevenson]

when using a Hikvision NVR, set h.264+ to "on" for the NVR's encoding server

Just to clarify -
Ignoring the high-end models such as the Ultra series that have transcoding facilities, video from attached cameras is simply recorded 'as-is'.
The encoding is done in the camera itself using the in-built DSP (digital signal processor) and the resulting encoded video stream supplied to the NVR for storage.

 

[ABCcam]

Thank you for the input - much appreciated as i am almost at the point of returning this cam.

To clarify - the real issue to resolve is image quality / video stability at night with colour image with lighting from diffused LED floodlights.

So far:

• Reducing the ghosting results in flicker/freezing
• Reducing or removing the flicker/freezing results in ghosting/halo

Game to try any suggestions although some may even be re-visited (definitely worthwhile as there is a multiplicity of possible settings and very possible one combination has been missed)

1. - I Frame interval - have tried all multiples of 25 up to 200 and 1 & 5.
There is though no reason to suspect the issue is bandwidth - all connections to cam use gigabit adapters and fiber.
25 was found to be best for day although the difference compared to 5 or 50 is not noticeable.
--> if it works fine without any freezing in day time with i Frame = 5 or 25 then there should not be any reason why this is an issue at night?

2. - Will try 2688 × 1520 (5mp) @25fps (we are on 50hz so max fps = 25)
(note: 1920x1080 did not make any difference)

3. We are running on CBR (VBR was suggested by HIKvision support) although we see no difference if it is CBR or VBR

 

[dimammx]

Yea looking at other videos from you, the flicker does not look light-related.
The glitches are so frustrating, and hard to debug! Dealing with Dahua cam right now that occasionally when encountering a moving person will cause a digital pixelated trail.
Tried pretty much every setting, and will be trying different NVRs just to make sure it is not NVR related.

 

[ABCcam]

Hi @dimammx
My experience and opinion of Dahua cams is not flattering - i have two that are gathering dust simply because they are not worth using..

 

[dimammx]

My environment is 65% Dahaua, 30% Hikvision, and 5 % some other brands, I do like the web interface and menus on Dahua more compared to Hikvision.