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Dahua new NVR series - performance and specifications

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Hello!

 

Anyone got their hands on Dahua NVR 41XX series? According to the specs, the series are limited by incoming total bandwidth of 80 mbps (record rate) and outgoing total bandwidth of 8mpbs (bit-rate), and they can record in resolutions of up to 5MP. So, in theory, one should be able to throw in 10 cameras, streaming at 5MP, 8 mbps CBR, and 30 FPS, and the NVR should record without reducing the quality, right? Also, because of the maximum 8mbps outgoing bandwidth, one can playback remotely only single channel at full quality, correct?

 

I found out that the "smart search" function is available only locally and not remotely via web or CMS. Do you know if they plan to fix that soon in some firmware/software update?

 

I'm open and looking forward to suggestions about the Dahua or any other budget products! Please, share your insight and experience!

 

Thank you in advance!

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80Mbps is the total bitrate combined from main stream and extra stream(which is usually around 10-12Mbps/channel, depending on settings).

 

So 80Mbps would give you aprox. 8 cameras - depening on the max number of channels the NVR can decode and the max resolution of the input channels.

Yes, playback is limited to that bandwidth. At this point, SmartSearch cannot be done via WEB since it requires additional resources. There is no word(as from what I know) if and when they will implement it remotely.

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80Mbps is the total bitrate combined from main stream and extra stream(which is usually around 10-12Mbps/channel, depending on settings).

 

So 80Mbps would give you aprox. 8 cameras - depening on the max number of channels the NVR can decode and the max resolution of the input channels.

Yes, playback is limited to that bandwidth. At this point, SmartSearch cannot be done via WEB since it requires additional resources. There is no word(as from what I know) if and when they will implement it remotely.

 

Hey, thanks for the reply!

 

Lets take for example Dahua NVR 4116. It has 16 channels, 80mbps incoming bandwidth and up to 5Mp resolution preview & playback, the specs also says that the max recording resolution is 5Mp. So, in theory, it should be good to go with 16 5MP cameras, each streaming at 5mpbs CBR and at maximum resolution, right?

 

Most of the Dahua IPC I've seen are limited to 8mpbs outgoing bandwidth /bit-rate/, which is why I think they can't output 10-12 mpbs. Is my assumption correct?

 

Btw, what is the meaning of "preview" resolution in this context?

 

Thank you!

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Lets take for example Dahua NVR 4116. It has 16 channels, 80mbps incoming bandwidth and up to 5Mp resolution preview & playback, the specs also says that the max recording resolution is 5Mp. So, in theory, it should be good to go with 16 5MP cameras, each streaming at 5mpbs CBR and at maximum resolution, right?

Not really. As I stated before, you have to sum up extra stream + main stream bitrate, not just main stream's bitrate. Should work if you setup 4Mbps for main stream and 1Mbps for extra stream. But 4Mbps for 5MP resolution is kind of low.

 

Most of the Dahua IPC I've seen are limited to 8mpbs outgoing bandwidth /bit-rate/, which is why I think they can't output 10-12 mpbs. Is my assumption correct?

As I stated, sum up both main and extra. Preview cams of DAHUA (UHD/4K) have a higher bitrate than 8Mbps, for example. Though, I don't recall higher than 8Mbps for current 5MP models.

 

Btw, what is the meaning of "preview" resolution in this context?

Preview refers to what the NVR decodes on local display. For example, a NVR could record 4 channels@1080p, but only display/decode 2 channels.

 

Also, please be advised that these specs are only for conenction with DAHUA's own cameras. If you want other manufacturers(via ONVIF, for example), there might be some issues.

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[quote="dexterash"] Not really. As I stated before, you have to sum up extra stream + main stream bitrate, not just main stream's bitrate. Should work if you setup 4Mbps for main stream and 1Mbps for extra stream. But 4Mbps for 5MP resolution is kind of low. [/quote] But the sub-stream is only needed if I want to watch it through smartphone for example, right? I suppose it is an option not requirement, correct? [quote="dexterash"] Preview refers to what the NVR decodes on local display. For example, a NVR could record 4 channels@1080p, but only display/decode 2 channels. [/quote] The specs says that the NVR has "sync playback: 1/4/9/16", which I assume means playback of 1 or 4, or 9, or 16 channels simultaneously and remotely at resolutions of up to 5MP, is it correct? It also says that the local display resolution is 1080p and the "Display-split: 1/4/8/9/16", which I assume has the exact same meaning as the above but with lower resolution, correct? I assume you mean decoding records, playback, not live view decoding, correct? But then it is in contradiction with the 1080p real-time live view specs. Or maybe Dahua specs has other meaning for "preview".

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Btw, the specs doesn't say how many channels the NVR can preview, only that it can preview at up to 5Mp resolutions.

 

Here is link to the discussed NVR specs. It would be kind of you if you can take a look!

 

Thank you!

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But the sub-stream is only needed if I want to watch it through smartphone for example, right? I suppose it is an option not requirement, correct?

Not really. Substream is also used by NVR when main is split in 4 cameras, for example. So the NVR always streams substream.

Also PSS/SmartPSS will display the Substream, instead of main stream, if multiple camera split is selected - to save bandwidth.

 

The specs says that the NVR has "sync playback: 1/4/9/16", which I assume means playback of 1 or 4, or 9, or 16 channels simultaneously and remotely at resolutions of up to 5MP, is it correct?

Local. Not remotely. Sync playback is not availabe remotely (yet).

There is a simple trick: yes, it can local playback a 5MP recording, but downscale it to 1080p.

 

I assume you mean decoding records, playback, not live view decoding, correct? But then it is in contradiction with the 1080p real-time live view specs. Or maybe Dahua specs has other meaning for "preview".

It's a little bit complicated. NVRs have (now) 5 specs:

-incoming(input) bandwidth/bitrate - the "general" that can be pulled by the NVR from the network

-recording bandwidth/bitrate - on this depends the local recording, but isn't linked to local display/decode; pure storage

-outgoing bandwidth/bitrate - depending on this are the remote preview&playback capabilities of the NVR

-preview bitrate/resolution - for cameras locally displayed/decoded, on NVR's HDMI output

-playback bitrate/resolution - for cameras locally playbacked, on NVR's HDMI output

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Btw, the specs doesn't say how many channels the NVR can preview, only that it can preview at up to 5Mp resolutions.

 

Here is link to the discussed NVR specs. It would be kind of you if you can take a look!

 

Thank you!

The total number of channels that it can preview is set by the XX in NVR41XX. But, as you also noticed, the complete resolution vs bitrate that the NVR can decode isn't stated - you'll have to get that info from your seller; in fact, DAHUA works hard on optimizing their firmwares and it might happen like this: today it can only decode 4 x 5MP channels, but a month later it will decode 8 x 5MP channells. That's also why they recommend to buy products from authorized dealers, so you can always have support and be in touch with latest updates.

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Not really. Substream is also used by NVR when main is split in 4 cameras, for example. So the NVR always streams substream.

Also PSS/SmartPSS will display the Substream, instead of main stream, if multiple camera split is selected - to save bandwidth.

 

So the NVR always need camera main stream+substream if one would want to watch real-time live view remotely multiple cameras because of the 8mpbs outgoing limit? Can't the NVR accept only main stream and then internally split it into multiple outgoing streams? I suppose the recording of the substream in that case isn't necessary, right, or is it mandatory? One can't simply record 4 x 4mbps streams because they will exceed the 8mbps NVR outgoing bandwidth and should record 4 + 4 mbps + 4 x 2mbps for example and then can view 4 cameras at once, is that right, or is there option for some stream/channel to skip recording /only real-time live view/?

 

Local. Not remotely. Sync playback is not availabe remotely (yet).

There is a simple trick: yes, it can local playback a 5MP recording, but downscale it to 1080p.

 

So remote playback is available only for single channel at a time, right? Also, if I'm on the right track, single channel is equal to single stream, correct?

 

-outgoing bandwidth/bitrate - depending on this are the remote preview&playback capabilities of the NVR

 

By remote preview I suppose you mean realtime-live view, right, and in my case it is limited to 8mpbs by the NVR outgoing bandwidth?

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The total number of channels that it can preview is set by the XX in NVR41XX.

 

That it can preview locally.

 

Btw, if preview and real-time live view means the same thing, why the different terms? Perhaps it is a preview of the live stream.

 

But, as you also noticed, the complete resolution vs bitrate that the NVR can decode isn't stated - you'll have to get that info from your seller; in fact, DAHUA works hard on optimizing their firmwares and it might happen like this: today it can only decode 4 x 5MP channels, but a month later it will decode 8 x 5MP channells. That's also why they recommend to buy products from authorized dealers, so you can always have support and be in touch with latest updates.

 

If the only job of the NVR is to act as a storage, then why it need to decode, can't it simply pass-through the streams?

 

The seller pretty much said that everything is based on the record and outgoing bandwidth, in my case 80 and 8mbps. That I can do anything within these values.

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So the NVR always need camera main stream+substream if one would want to watch real-time live view remotely multiple cameras because of the 8mpbs outgoing limit? Can't the NVR accept only main stream and then internally split it into multiple outgoing streams? I suppose the recording of the substream in that case isn't necessary, right, or is it mandatory? One can't simply record 4 x 4mbps streams because they will exceed the 8mbps NVR outgoing bandwidth and should record 4 + 4 mbps + 4 x 2mbps for example and then can view 4 cameras at once, is that right, or is there option for some stream/channel to skip recording /only real-time live view/?

Usually, yes. If not, then there will be some cases where you'll not have image on mobile/pss/local (when the NVR/application needs the substream). And no, the NVR doesn't do any recoding/splitting. Recording the extra is a good thing if you want to view recording over slow Internet connections. Outgoing bandwidth has nothing to do with NVR's recording caps, but with what it can resend to another client

 

So remote playback is available only for single channel at a time, right? Also, if I'm on the right track, single channel is equal to single stream, correct?

As from specs and from my experience with DAHUA products is seems right. Maybe it can be possible to remote playback 4 substreams@2Mbps that summed up will be 8Mbps - in this case you really need substream recording.

 

By remote preview I suppose you mean realtime-live view, right, and in my case it is limited to 8mpbs by the NVR outgoing bandwidth?

Yes. But you can always connect directly to the cameras.

 

Btw, if preview and real-time live view means the same thing, why the different terms? Perhaps it is a preview of the live stream.

As fromwhat I can deduct, small problems at translation from chinese to english.

 

If the only job of the NVR is to act as a storage, then why it need to decode, can't it simply pass-through the streams?

Local view@NVR = decode. Also, the NVR has to do some indexing/information extraction(metadata) from the streams.

 

The seller pretty much said that everything is based on the record and outgoing bandwidth, in my case 80 and 8mbps. That I can do anything within these values.

Your seller might be wrong. If it's a big, trusted seller than go along that way. If it's eBay or some other kind of 3rd party that just wants to sell I would raise some question marks.

 

I've attached how a decent/true NVR spec table should look like.

nvr_specs.thumb.png.c56c49ab9cd80028182198a7022f67e9.png

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Yes. But you can always connect directly to the cameras.

 

But if I bypass the NVR and connect directly to the camera then I would borrow bandwidth from its main stream or I would need extra stream that will reduce the available bandwidth for the main. Purely theoretical, that would be the case only if the camera main stream is maxed. I believe that in real scenario 4 mpbs stream is more than enough for decent 2MP and 2mps for 1.3MP. Btw, are the number of the IPC substreams limited by total bandwidth only?

 

I've just noticed that Dahua IPCs are marketed as 1.3MP 1280x1024 when they're more like 1.2MP = 1280x960. At least that is that the specs says about the effective resolution. Guess it is another marketing stunt.

 

As fromwhat I can deduct, small problems at translation from chinese to english.

 

Chinglish seems very convenient when it comes to that.

 

Local view@NVR = decode. Also, the NVR has to do some indexing/information extraction(metadata) from the streams.

 

Maybe decoding is also needed for the Motion Detection function to work. I've been told that it is done by the NVR.

 

Your seller might be wrong. If it's a big, trusted seller than go along that way. If it's eBay or some other kind of 3rd party that just wants to sell I would raise some question marks.

 

It is the only seller in my country and it seems fairly big but its employees are slightly more arrogant than they should be! I've already given a thought about going down the Ebay road, even for cheap solutions with flashy claims, and after a while decided that it's not a wise choice, mainly because of the warrant, support, and that the sellers I've contacted so far have no clue what they're selling, which is a real stopper.

 

I've attached how a decent/true NVR spec table should look like.

 

It would be a real relief if manufacturers and sellers heed your words! I really hope they do for the sake of all customers!

 

Btw, I have a quick side question. It is a bit outside the scope but I hope you don't mind. So, here it goes, the question is, is there any correlation between the IPC fps and resolution in the context of stream bandwidth (bit-rate)? Can 1.3MP IPC be set to stream at 1.3MP@30fps as well as @1fps? Well, I suppose it can and obviously more fps would mean more bandwidth but is there any catch that I should be aware of? I am asking because I read in the specs the following "1.3M/720P(1 ~ 25/30fps)" for the main stream.

 

 

I really want to thank you for your efforts so far! I really appreciate it!

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But if I bypass the NVR and connect directly to the camera then I would borrow bandwidth from its main stream or I would need extra stream that will reduce the available bandwidth for the main. Purely theoretical, that would be the case only if the camera main stream is maxed. I believe that in real scenario 4 mpbs stream is more than enough for decent 2MP and 2mps for 1.3MP. Btw, are the number of the IPC substreams limited by total bandwidth only?

Nope, if you connect directly to the cameras there shouldn't be any problems. Any DAHUA IP Camera can support 4-5 8Mbps (40Mbps in total or more) of uploading. We usually setup cameras at CBR, max bitrate available. More space occupied, yet better results. How would you compare 3.6GB/hour with 1080p BlueRay Quality?

 

I've just noticed that Dahua IPCs are marketed as 1.3MP 1280x1024 when they're more like 1.2MP = 1280x960. At least that is that the specs says about the effective resolution. Guess it is another marketing stunt.

Oppose to what you have seen (probably on different websites), DAHUA usually under-market their products or maybe is a bad translation.Don't know if it's a habbit, but they have a tendancy to do better products than they advertise(or invest in marketing/support).

 

Chinglish seems very convenient when it comes to that.

You're right!Where did you catch that term?

 

Maybe decoding is also needed for the Motion Detection function to work. I've been told that it is done by the NVR.

BullsHomethIng. MD is done by cameras. NVRs only take "signals" of MD and store that in some logs.

 

It is the only seller in my country and it seems fairly big but its employees are slightly more arrogant than they should be!

Can you state the country, out of pure curiosity?

 

I've already given a thought about going down the Ebay road, even for cheap solutions with flashy claims, and after a while decided that it's not a wise choice, mainly because of the warrant, support, and that the sellers I've contacted so far have no clue what they're selling, which is a real stopper.

As usual, bulk sellers.

 

It would be a real relief if manufacturers and sellers heed your words! I really hope they do for the sake of all customers!

Manufacturers somehow do, sellers are the problem around this.

 

Btw, I have a quick side question. It is a bit outside the scope but I hope you don't mind. So, here it goes, the question is, is there any correlation between the IPC fps and resolution in the context of stream bandwidth (bit-rate)? Can 1.3MP IPC be set to stream at 1.3MP@30fps as well as @1fps? Well, I suppose it can and obviously more fps would mean more bandwidth but is there any catch that I should be aware of? I am asking because I read in the specs the following "1.3M/720P(1 ~ 25/30fps)" for the main stream.

Yes it can be set. No catch there.

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Nope, if you connect directly to the cameras there shouldn't be any problems. Any DAHUA IP Camera can support 4-5 8Mbps (40Mbps in total or more) of uploading. We usually setup cameras at CBR, max bitrate available. More space occupied, yet better results. How would you compare 3.6GB/hour with 1080p BlueRay Quality?

 

The specs about IPC-HFW4100S says main stream at 1.3M/720P(1 ~ 25/30fps), substream at D1/CIF(1 ~ 25/30fps) and max bandwidth (bit-rate) 8mbps. And I got that the given IPC support only 1 main and 1 substream within 8mbps limited bandwidth. As you can see it is pretty hard one to understand what is meant. But after you shed some light, now it looks like the given maximum bandwidth is per stream of some unknown number of streams /usually 4-5 as you wrote/.

 

Is there noticeable difference between 2MP (1080p) at 4mpbs and at 8mpbs /for the naked eye/? Again, I've been told there isn't, yet the presentation was quick and I had no luck seeing it for myself.

 

3.6GB/h is at 8mpbs and to be honest I don't think it is even close to comparable with BR quality. After all, it is some "cheap" camera and I'm not fooling myself, not even looking for BR quality in budget cameras, but I expect something that hopefully will considerably outperform all mass analogue variants on the market.

 

Oppose to what you have seen (probably on different websites), DAHUA usually under-market their products or maybe is a bad translation.Don't know if it's a habbit, but they have a tendancy to do better products than they advertise(or invest in marketing/support).

 

Good to hear but the info is from the Dahua official website and official IPC specs there - Link. All 1.3MP IPC specs there says that the effective pixels are 1.2MP = 1280Hx960V. It is hard to mistranslate

numbers even in Chinglish.

 

You're right!Where did you catch that term?

 

Can't recall, just popped out of my mind. Why, you like it, don't you?

 

BullsHomethIng. MD is done by cameras. NVRs only take "signals" of MD and store that in some logs.

 

I've been told by the official reseller that the entire process of recording based on Motion Detection is done entirely by the NVR, even the MD itself. The reseller employees said that the IPC stream is continuous, regardless of whether actual motion is being detected or not, and that the NVR decides whether to record or not (i.e., if it detects motion).

 

Can you state the country, out of pure curiosity?

 

Sure thing! It's Bulgaria.

 

Manufacturers somehow do, sellers are the problem around this.

 

I'm inclined to agree to some extend with you. But obviously "somehow" is not enough. Perhaps some of the manufacturers relies too heavily on resellers to do the job.

 

Yes it can be set. No catch there.

 

Let me paraphrase the question. Can the main stream of 1.3MP camera be set to 4mpbs@30fps or is it maxed when the fps is maxed out?

 

- 1.3MP@8mbps@30fps

- 1.3MP@4mbps@15fps

- so on

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Taking a deep breath and:

The specs about IPC-HFW4100S says main stream at 1.3M/720P(1 ~ 25/30fps), substream at D1/CIF(1 ~ 25/30fps) and max bandwidth (bit-rate) 8mbps. And I got that the given IPC support only 1 main and 1 substream within 8mbps limited bandwidth. As you can see it is pretty hard one to understand what is meant. But after you shed some light, now it looks like the given maximum bandwidth is per stream of some unknown number of streams /usually 4-5 as you wrote/.

There is a tricky difference between bitrate(which refers to stream quality/compression/blah blah) and bandwidth.

 

Is there noticeable difference between 2MP (1080p) at 4mpbs and at 8mpbs /for the naked eye/? Again, I've been told there isn't, yet the presentation was quick and I had no luck seeing it for myself.

Yes, it is a big difference, especially in motion-full scenes. If you want to understand more, read about the H.264 and how it sends frames that are only consisted of differences from previous frames(I can't find a simple way to explain it:).

 

3.6GB/h is at 8mpbs and to be honest I don't think it is even close to comparable with BR quality. After all, it is some "cheap" camera and I'm not fooling myself, not even looking for BR quality in budget cameras, but I expect something that hopefully will considerably outperform all mass analogue variants on the market.

Not BDray, but:

Swicth it to 1080p, let youtube reload, pause on a frame and observe the details.

 

Good to hear but the info is from the Dahua official website and official IPC specs there - Link. All 1.3MP IPC specs there says that the effective pixels are 1.2MP = 1280Hx960V. It is hard to mistranslate

numbers even in Chinglish.

DAHUA's website has some flaws and, sometimes, it's not even updated. We updata and test a lot(I mean, a lot ) of DAHUA products and usually the specs are better than those initial specs on website(yes, descriptions on website are initial specs).

 

Can't recall, just popped out of my mind. Why, you like it, don't you?

I use it too.

 

I've been told by the official reseller that the entire process of recording based on Motion Detection is done entirely by the NVR, even the MD itself. The reseller employees said that the IPC stream is continuous, regardless of whether actual motion is being detected or not, and that the NVR decides whether to record or not (i.e., if it detects motion).

BullsHomething 2. Yes, the stream is continous. Yes, the NVR does the record. BUT the NVR starts the recording when a motion event is sent from the camera. Thus said, besides the Video Stream there is a stream of METADATA/CONTROL from the camera to the NVR and vice-versa.

 

I'm inclined to agree to some extend with you. But obviously "somehow" is not enough. Perhaps some of the manufacturers relies too heavily on resellers to do the job.

This is where the "cheap" comes from. The manufacturer only manufacturers, it's the resellers job to support, market and resell the product. That is why is very important to chose a good reseller (and one agreed by DAHUA).

 

Let me paraphrase the question. Can the main stream of 1.3MP camera be set to 4mpbs@30fps or is it maxed when the fps is maxed out?

Max Bitrate is lowered when the FPS is lowered. Yes, your examples are close to reality.

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There is a tricky difference between bitrate(which refers to stream quality/compression/blah blah) and bandwidth.

 

How so? The maximum bandwidth (given as bitrate in the specs) per video stream is 8mbps. I am not referring to the maximum bandwidth of the device Ethernet port, which in the given IPC is 100mpbs, or the total bandwidth for all number of streams because there isn't such info. I meant and said stream bandwidth but also as I stated already, the vague specs does not make it easy.

 

Yes, it is a big difference, especially in motion-full scenes. If you want to understand more, read about the H.264 and how it sends frames that are only consisted of differences from previous frames(I can't find a simple way to explain it:).

 

The root of the problem must be the correlation between the FPS and the bit-rate. Lower bit-rate means lower fps, which in turn means less smooth motion scenes. That would be a problem with all kind of video signal. But if there isn't too much motion then this shouldn't be an issue.

 

If we put the motion scenes aside, is there noticeable difference in the details?

 

Not BDray, but:

Swicth it to 1080p, let youtube reload, pause on a frame and observe the details.

 

I've already seen that video and many more. But I am not sure what were the stream details at the time the video was taken.

 

DAHUA's website has some flaws and, sometimes, it's not even updated. We updata and test a lot(I mean, a lot ) of DAHUA products and usually the specs are better than those initial specs on website(yes, descriptions on website are initial specs).

 

I understand but that doesn't make it look good.

 

I use it too.

 

Kudos!

 

This is where the "cheap" comes from. The manufacturer only manufacturers, it's the resellers job to support, market and resell the product. That is why is very important to chose a good reseller (and one agreed by DAHUA).

 

I'm pretty sure that is not the only reason. There are surely things like cheap labor and etc. But otherwise totally agree with you. Dahua referred me to the reseller I'm dealing with.

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