DH-IPC-HDW3849H-AS-PV-S3 jelly footage

[Dobiwallah]

Because I had good results with the IPC-HDW3849H-AS-PV on my driveway, I decided to purchase a DH-IPC-HDW3849H-AS-PV-S3, the improved version of the IPC-HDW3849H-AS-PV, to replace the IPC-HDBW4800E-S which was missing cars on the recordings.

But I can't get the footage sharp. I have done similar settings as my IPC-HDW3849H-AS-PV, which doesn't have these problems on my driveway. am I missing something, or is there something wrong with the camera?

 

[sebastiantombs]

I'd say to use H264 and not H265. I'd also match frame and iframe rates as well as use constant bit rate for both main and sub streams.

 

[Dobiwallah]

It has improved when the picture is idle, but when a car drives by, it still getting a bit blurry. I cant control the iframe from my recorder, I have to do that when I'm back home tonight. Normally I have it at 2x frame.

 

[wittaj]

You should drop the FPS and iframes to 15. Since this is a dual cam, the little processor is the same as for one camera, so you are overcooking it and it is stumbling. You should make these changes in the camera GUI to ensure they hold.

Shutter speed is more important than FPS. 25FPS is a waste of storage space and compromises your entire system.

Shutter speed gives you the ability to stop the video to get a clean capture. FPS only gives smoothness. But if it is maxing out the capacity of the camera, then other parameters have to give to make 30 FPS and that is usually slowing the shutter....

Keep in mind that these type of cameras, although are spec'd and capable of these various parameters, real world testing by many of us shows if you try to run these units at higher FPS and higher bitrates than needed that you will max out the CPU in the unit and then it bugs out just long enough that you miss something or video is choppy. My car is rated for 6,000RPM redline, but I am not gonna run it in 3rd gear on the highway at 6,000RPM...same with these types of units - gotta keep them under rated capacity. Some may do better than others, but trying to use the rated "spec" of every option available is usually not going to work well, either with a car or a camera or NVR.

Look at all the threads where people came here with a jitter in the video or IVS missing motion or the SD card doesn't overwrite and they were running 30FPS and when people tell them to drop the FPS and they dropped the FPS to 15FPS the camera became stable and they could actual freeze frame the image to get a clean capture. The goal of these cameras are to capture a perp, not capture smooth motion. When we see the news, are they showing the video or a freeze frame screen shot? Nobody cares if it isn't butter smooth...getting the features to make an ID is the important factor. As always, YMMV...

Further, these types of cameras are not GoPro or Hollywood type cameras that offer slow-mo capabilities and other features. They "offer" 30FPS and 60FPS to appease the general public that thinks that is what they need, but you will not find many of us here running more than 15 FPS; and movies are shot at 24 FPS, so anything above that is a waste of storage space for what these cameras are used for. If 24 FPS works for the big screen, I think 15 FPS is more than enough for phones and tablets and most monitors LOL. Many of my cameras are running at 12FPS.

In fact, many times if a CPU is maxing out, it will adhere to the FPS but then slow the shutter down to try to not max the CPU, which then produces a smooth blurry image..that is the video my neighbor gets who insists on running 60FPS. He gets smooth walking people but you can't freeze frame it cause every frame is a blur, meanwhile my 12FPS gets the clean freeze frame. Shutter speed is more important the FPS. We both run the same shutter speed by the way, but his camera CPU is maxing out and something gotta give when you push it that hard.

 

[Dobiwallah]

I lowered now to 15fps. It has improved another bit, but I don't think it will be any better. Still a small blur behind a car. But now I noticed the predecessor IPC-HDW3849H-AS-PV has also a blur trail. Maybe the IPC-HDBW4800E-S which was there before had just a better image quality... BTW, the DH-IPC-HDW3849H-AS-PV-S3 is a single cam.

 

[wittaj]

Oh yea, my bad. Got the alphabet soup numbers mixed up LOL.

But regardless, lowering the FPS will help even a singe cam.

Can you adjust the NR by going into the camera GUI? If you can drop it down to 30ish the trail will be minimized.

 

[bp2008]

Much of the advice above is specific to Blue Iris which I think is not being used here. Making iframe interval match frame rate is counterproductive when you are seeking higher quality. Longer iframe intervals will typically yield better quality.

4K cameras are very hungry for bandwidth. If you can't increase the bit rate further, then reduce the frame rate some more.

The H.265 encoder may be bugged such that H.264 looks better. It is unlikely but worth trying H.264 just to see.

If you are using a Dahua recorder, then feel free to turn on Smart Codec. It should improve compression efficiency quite a bit.

 

[Dobiwallah]

I read somewhere that you can't use smart codec with IVS. Or am I confused with H265+, which I thought is smart codec? DahuaWiki

 

[bp2008]

I dunno, maybe you can't use it with IVS. I've never used either really.

H.265+ and smart codec are basically the same thing, yes.

 

[bigredfish]

Couple of suggestions, I’ll wager you’ll get rid of blur.

• use the camera GUI itself to make changes. Always. You’re not even seeing all of the settings. Using the limited settings on the NVR will create problems for you.
• change to CBR not VBR
• I’ve always matched Iframe to fps
• what exposure/shutter speed are you running? Daytime try customized range 0-2 or 0-4
• daytime DNR 30 should be plenty
• Leave gain at 0-50

Night will be a whole different set of settings…

 

[msquared]

There seems to be two schools of though regarding fps and iframe settings. There are numerous mentions to match fps and iframe, but a post above mentions that matching is counterproductive to higher quality. I apologize if this is OT and hijack the thread, but can someone explain what benefits or drawbacks to matching or not matching fps and iframe? specifically regarding how matching can be counterproductive to quality?

 

[bigredfish]

Two great articles by IPVM on FPS and frame-rate/Iframe

For quality, I run 30 FPS, CBR, and match Iframe to FPS (one Iframe per second). For things like LPR it’s more important.

Frame Rate Guide for Video Surveillance

This is the industry's most in-depth guide to frame rates in video surveillance with more than a dozen visual examples to show the trade-offs involved.

ipvm.com

Test: H.264 I vs P Frame Impact

IPVM is the world's authority on physical security technology, profiled by Time, The Atlantic, Wired and collaborated with the BBC, NY Times, Reuters, WaPo, WSJ, and more.

ipvm.com

 

[bp2008]

If longer iframe intervals are reducing quality as IPVM found, then that would indicate the iframes are encoded at higher quality than the p-frames. Funny, because when Blue Iris encodes an H.264 video it is the opposite, where i-frames look worse than p-frames.

 

[msquared]

I just read the article myself, I hope I interpreted this correctly...so the encoder plays a part in determining the iframe/p-frame relationship, the encoder in the camera hardware or the encoder in the software? What if there is a conflict between the two encoders? Just looking for clarity so newer users can implement best practices when setting up their cams.

 

[bp2008]

There seems to be two schools of though regarding fps and iframe settings. There are numerous mentions to match fps and iframe, but a post above mentions that matching is counterproductive to higher quality. I apologize if this is OT and hijack the thread, but can someone explain what benefits or drawbacks to matching or not matching fps and iframe? specifically regarding how matching can be counterproductive to quality?

I'm not 100% convinced by ipvm's analysis where they concluded that longer iframe intervals resulted in lower quality. They didn't specify most of the encoding settings they were using, and their demonstration video was this super low res thing from one unspecified camera. It was also published 8 years ago and technology has changed a lot since then. I haven't done scientific tests myself. Its a lot of work

Pros of more i-frames (smaller i-frame interval):

• Faster seeking in recorded video
• Faster startup when freshly opening a live stream
• More precision when beginning a recording. Recordings can only begin with an i-frame, so if they are spaced too far apart, recordings may start at awkward times.

Pros of fewer i-frames:

• i-frames are huge, so having fewer of them means they use less of your total available bit rate. This means more of the bit rate can get allocated to p-frames (which are most of the frames in the video stream), so the video quality can be better overall. (* this assumption can be broken if the camera's encoder is tuned such that p-frames are lower quality than i-frames for some reason).

Most cameras do perform just fine with FPS and i-frame being equal to each other, as long as you give them enough bit rate!

I just read the article myself, I hope I interpreted this correctly...so the encoder plays a part in determining the iframe/p-frame relationship, the encoder in the camera hardware or the encoder in the software? What if there is a conflict between the two encoders? Just looking for clarity so newer users can implement best practices when setting up their cams.

I'm not sure what you are referring to. The video encoder is in the camera hardware. Some software can re-encode video but that is a really inefficient thing to do so it is avoided whenever possible in most video software. There's really no way for there to be a "conflict" between encoders.

A video encoder is a thing that takes raw video data and compresses it. A decoder takes the compressed video and returns it to its raw format. But the encoding step loses some of the information. So you really don't want to have two encoders in your video pipeline because you'll lose quality twice.

 

[msquared]

Thank you for the info. My question wasn't clear. It was the reference to best practices for setting i and p frames, and how this affects quality in different software (i.e. Blue Iris behaves better when i and p frame match). Your explanation above helped. There is the perpetual mention to use H264 with no proprietary smart codec, instead of H265. Which level of H264 is best (in general, or specifically for Blue Iris) for capture quality (not doing a deep dive into fps, shutter speed, bit rate, storage space, bandwidth, etc.) H264, H264B, or H264H? A general assumption is that more compression affects quality. I can start a new thread if anyone feels I am out of my lane by asking this. I felt it was relevant since OP asked for best settings regarding picture quality.

 

[looney2ns]

Thank you for the info. My question wasn't clear. It was the reference to best practices for setting i and p frames, and how this affects quality in different software (i.e. Blue Iris behaves better when i and p frame match). Your explanation above helped. There is the perpetual mention to use H264 with no proprietary smart codec, instead of H265. Which level of H264 is best (in general, or specifically for Blue Iris) for capture quality (not doing a deep dive into fps, shutter speed, bit rate, storage space, bandwidth, etc.) H264, H264B, or H264H? A general assumption is that more compression affects quality. I can start a new thread if anyone feels I am out of my lane by asking this. I felt it was relevant since OP asked for best settings regarding picture quality.

All of this is somewhat scene specific, settings that work for one location, won't work as well in another location possibly.
You need to test each of your camera locations and tune accordingly.
In general, many feel that plain ole h264 gives the best quality.