Member Discussion

Samsung Video Problem - Grainy Than Clear, Repeats


Recently put in 9 Samsung SNV-6084. Everything went well but im getting werid issue the image becomes grainy then clear. Repeats over again. More apparent at night. Even daylight some roads that are black/Gray you see this effect but not as noticeable as it is at night. Also I am using H264 and exacq vms. I noticed when I export video and turn on H264 deblocking this effect goes away on replay.

Im sure something simple but like to know where to start.


PS where is spellcheck? :)

Hi Lee,

Can you share a short video or image? It's hard to guess abstractly what he is happening.

How long of a period between 'repeats'? A few seconds? A few minutes?

As for H.264 deblocking on Exacq, I've forwarded them this discussion and asked for a response.

I have not noticed this with the SNV6084 and Security Center 5.2 or through a Web browser (Chrome or IE). Could it be a specific WDR or SSNR setting?

Sean, thanks for the feedback. Can you describe it a little more or share a pic?

So "grainy" might not be right description I would call it "blocking"

The images below are only one to two frames apart.

I am not sure how to upload a video.

Camera is default except for the minimum shutter from default 1/5 to 1/30. I don't think WDR is turn on by defualt.

SSNR what do i adjust in that field?

So goes like this

Clear image, blocking effect comes for 5 seconds an progressively get worse in those seconds then clear image again. Then repeat.

frame before

frame after

With the exported video I count to the next clear frame. Seems to come every 30 frames to the next clear picture. Not sure if that helps.

More info

Camera is setup for 7fps and recording at the highest resolution.

Compression doesn't seem to help or worsen the issue.

External IR is being used as well.

thanks for replays!

Lee, what is your GOV set for? It's listed under Video Profile setup. If you're using 7 FPS, you should set it to 7. I believe it defaults to 30, which would only give you an I frame every 4+ seconds. With that many P-frames, image quality deteriorates before clearing when the camera sends a new I frame. More details on this in our I Frame test report.

The bigger part I believe is due to how Exacq decompresses H.264 streams. According to their manual, the H.264 de-blocking option results in more detailed decompression. In the clip you linked to from our Samsung test, you can see that by turning the option on and off. I personally recommend leaving it set to "By Device", which will turn it on if the camera supports it. According to the manual, enabling it can reduce client performance. I haven't seen this myself, but I have not specifically looked at load with de-blocking on and off.

We've asked Exacq for comments and recommendations on this option and will update when they reply.


Good to know I am thinking that is the issue. I changed cameras to 7 for the GOV. And see if that takes care of it. So is this something that sould be done for all ip camera manf. When you lower the FrameRate match that with the GOV setting for H264 profiles?

Well, GOV setting at 7 doesn't seem to have changed the blocking effect. Still takes 4+ seconds for the next clean image. :(

This "deblocking" a common option for VMS systems or cameras?

Other Samsung cameras have it as an explicit option, like this SNC-B2331:


One question Lee, it looks like there is basically no motion in those pics, is that true?

If so, one would think that the delay between I-frames could be quite long without causing severe degradation.  

One question Lee, it looks like there is basically no motion in those pics, is that true?

If so, one would think that the delay between I-frames could be quite long without causing severe degradation.

Not in the night shots don't have much motion but it is a new install need to adjust the senitivity and motion areas false alarms that are triggering motion. But the daytime has more motion of coarse.

I don't have remote access to the physical cameras settings yet. I'll have to check for that deblock in video profile. Thanks

Been looking at Samsung camera shootout again notice samething in your video as well. If I turn on the H264 deblocking it goes away.

Is this a H264 setting in the camera that could help alleviate the issue?