What does this do? Does setting smart codec to "open" save space?
Is there a reduction in image quality?
How does smart codec work?
Is there a reduction in image quality?
How does smart codec work?
Smart Codec.
- Thread starter nuraman00
- Start date
Smart codecs aim to reduce bandwidth consumption without losing visible image quality by intelligently increasing compression where it will not make a [visible] difference in the scene. See our guide unlocked Smart Codec Guide
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Just as a FWIW, some Dahua cameras disable/hide IVS (advanced motion detection) when the smart codec is enabled.
Thanks. Right now, all I have is one camera with simple motion detection. The others are 24/7.
Do you think I should enable smart codec?
@EMPIRETECANDY
Why do I have different hard drive capacity readings, based on the software?
When I use the Web Service, it says I've used 6.97 / 7.27.
That's about 300 GB in 43 hours.
I have 7 cameras set to 24/7, and the garage camera set to motion only.
They are all set to 15 fps. Although for the first 1 or 2 hours, they were set to 25 fps, and also using H264. I didn't change them until 1 or 2 hours after the initial set up, when I found that part of the menu.
Smart PSS says I've used 7145.62 GB of 7451.80. That's about 306 GB. That comes out to 170.79 GB per day.
Which reading do I believe?
Also, according to Disk Calculator (from the Dahua Toolbox), I should only be using 78.15 GB a day. I calculated using 7 cameras, because the garage one only records a few minutes a day.
Why are the calculations by Disk Calculator, and my actual recording capacity in these initial 43 hours, so different?
Why do I have different hard drive capacity readings, based on the software?
When I use the Web Service, it says I've used 6.97 / 7.27.
That's about 300 GB in 43 hours.
I have 7 cameras set to 24/7, and the garage camera set to motion only.
They are all set to 15 fps. Although for the first 1 or 2 hours, they were set to 25 fps, and also using H264. I didn't change them until 1 or 2 hours after the initial set up, when I found that part of the menu.
Smart PSS says I've used 7145.62 GB of 7451.80. That's about 306 GB. That comes out to 170.79 GB per day.
Which reading do I believe?
Also, according to Disk Calculator (from the Dahua Toolbox), I should only be using 78.15 GB a day. I calculated using 7 cameras, because the garage one only records a few minutes a day.
Why are the calculations by Disk Calculator, and my actual recording capacity in these initial 43 hours, so different?
I can take screen shots of the framerate configuration from my actual cameras, in case someone wants to see if I can improve it.
Also, while this tool isn't a Dahua tool, it is another recording calculator.
DVR/NVR Record Time Calculator (now with both H.264 and H.265 support)
This one estimates that with 7 cameras at 24/7, it should use 99 GB a day with H.265.
So between both the Disk Calculator above, and this other calculator, I am expecting between 78 - 99 GB a day, not the 167 - 171 per day that it is actually doing.
DVR/NVR Record Time Calculator (now with both H.264 and H.265 support)
This one estimates that with 7 cameras at 24/7, it should use 99 GB a day with H.265.
So between both the Disk Calculator above, and this other calculator, I am expecting between 78 - 99 GB a day, not the 167 - 171 per day that it is actually doing.
I don't know what happened to @aristobrat's post. It was there a minute ago.
But I'll check the bitrate that my actual cameras are set to tonight, and take screen shots.
The 1084 kbps in the disk calculator was automatically filled out after I selected 2MP and Audio On.
Does my storage use per day seem normal, or high? If you have 2MP cameras and record 24/7, what is your storage rate?
But I'll check the bitrate that my actual cameras are set to tonight, and take screen shots.
The 1084 kbps in the disk calculator was automatically filled out after I selected 2MP and Audio On.
Does my storage use per day seem normal, or high? If you have 2MP cameras and record 24/7, what is your storage rate?
This is the bitrate I'm using:
Should I keep it the same, or lower it? What impact will lowering the bitrate have? Will it affect the overall image quality?
Should I be using constant or variable bitrate?
Should I keep it the same, or lower it? What impact will lowering the bitrate have? Will it affect the overall image quality?
Should I be using constant or variable bitrate?
The software may not accurate, just refer to the actual recording is fine.@EMPIRETECANDY
Why do I have different hard drive capacity readings, based on the software?
When I use the Web Service, it says I've used 6.97 / 7.27.
That's about 300 GB in 43 hours.
I have 7 cameras set to 24/7, and the garage camera set to motion only.
They are all set to 15 fps. Although for the first 1 or 2 hours, they were set to 25 fps, and also using H264. I didn't change them until 1 or 2 hours after the initial set up, when I found that part of the menu.
Smart PSS says I've used 7145.62 GB of 7451.80. That's about 306 GB. That comes out to 170.79 GB per day.
Which reading do I believe?
Also, according to Disk Calculator (from the Dahua Toolbox), I should only be using 78.15 GB a day. I calculated using 7 cameras, because the garage one only records a few minutes a day.
Why are the calculations by Disk Calculator, and my actual recording capacity in these initial 43 hours, so different?
So the actual recording is the one that uses the Web Service? Or how do I see the actual recording?
Also, should I enable Smart Codec?
And, what bitrate should I use? I posted what I'm using in #9. What happens if I lower it? What is the impact?
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NVR/Basic Setup/Resolution Explanation - Dahua Wiki
Check it here for the bit rate using. Also, should I enable Smart Codec?---NO problem.
Does anyone know why? Smart codec takes too much CPU resources, so other tasks are not possible?
fenderman
Staff member
- Mar 9, 2014
- 36,891
- 21,407
@aristobrat, @fenderman, @looney2ns
Thanks.
So the conclusion is that the 2 Mbps bitrate I am using is correct, for the 1920x1080 resolution, and I shouldn't lower it. What would it do if I lowered it? Would the quality get worse?
Just so I understand.
What about Constant vs. Variable bitrate? Any preference?
And for the disk space, is the Web Service the more accurate one, when compared to Smart PSS?
looney2ns
IPCT Contributor
Lowering the bitrate will use less storage space but will also degrade the picture some what. Try for yourself to see h o w it looks to you.
Vbr will in general use less storage. As it only records the part of the pic that changes from frame to frame. Again try it to See how it looks to you.
There is no right or wrong way. You have to decide what settings works best in your situation.
As for the last question, not certain what your asking.
Vbr will in general use less storage. As it only records the part of the pic that changes from frame to frame. Again try it to See how it looks to you.
There is no right or wrong way. You have to decide what settings works best in your situation.
As for the last question, not certain what your asking.
Thank you. I will try these things and see how they look this weekend. So VBR doesn't degrade the picture then, correct?
I see two different readings for storage space availability, including capacity. I want to use the more accurate one.
Smart PSS says I've had 7145.62 GB of 7451.80 available last week. That's about 306 GB.
At the same time, if I went to the IP address of the NVR, and used the Web Service UI, it said I've had 6.97 / 7.27 available, which was 300 GB.
That is not true. VBR fixes the quantization / compression level and allows the bandwidth to vary to maintain that compression level. CBR fixes the bandwidth level and varies the compression to fit within the bandwidth set. Whether it is VBR or CBR, any interframe compression (like MPEG-4, H.264, H.264) will 'only records the part of the pic that changes from frame to frame' so that part does not vary between VBR and CBR.
CBR is risky since is the bitrate is too low for what the scene needs, compression will be lowered. Imagine a school, empty on a Sunday vs when students are changing classes on the middle of Monday. On Sunday, with CBR, compression level will be quite low, since not much bandwidth is needed for an empty hallway. However, on mid-day Monday, compression level will spike and quality will be degraded as the camera is forced to stay within the set CBR level. The only way to prevent this is to set the CBR level quite high and then you are, by contrasting, wasting bandwidth on Sunday in this example. Net/net use VBR.
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The school analogy is a perfect example of a situation that can be served by both CBR and VBR.
The problem with VBR is that most camera processors are slow to “ramp up” to meet rapid changes in the image, which are quite visible as pixelization. They eventually smooth out, but crucial identification information can be lost.
Constant bitrates can prevent poor image quality caused by those rapid changes but a cost. It consumes significantly more bandwidth and storage.
If the bitrates are set incorrectly, CBR can have terrible image quality or consume far too much storage.
If done correctly, CBR image quality should be consistently superior to VBR and offer a guaranteed storage requirement.
It really depends on the customer expectations.
Sent from my iPhone using Tapatalk
The problem with VBR is that most camera processors are slow to “ramp up” to meet rapid changes in the image, which are quite visible as pixelization. They eventually smooth out, but crucial identification information can be lost.
Constant bitrates can prevent poor image quality caused by those rapid changes but a cost. It consumes significantly more bandwidth and storage.
If the bitrates are set incorrectly, CBR can have terrible image quality or consume far too much storage.
If done correctly, CBR image quality should be consistently superior to VBR and offer a guaranteed storage requirement.
It really depends on the customer expectations.
Sent from my iPhone using Tapatalk
I am not sure which specific camera manufacturers you are referring to, but we test and track the major professional ones (from Dahua and Hikvision to Axis, Avigilon, Bosch, Hanwha, Panasonic, Vivotek, etc) and we rarely see such issues when using VBR. Moreover, in our surveys and tracking, VBR is the default used by integrators, again with rare, if any issues.
That said, I don't doubt that really low cost cameras may have problems but we also generally don't test them.