If you are confused, do not worry. You should be. And we are going to explain how they differ here.

And yes, HD-SDI, HD-CVI, HD-TVI and HDcctv are just a few of the acronyms behind non IP HD video. Indeed, there is also AnalogHD, HD-AVS, HD-MPX and more.

There are two fundamental issues:

  • Incompatability Technologies
  • Similar Technologies but Re-Labelled

Let's break each down inside:

[NEW: HD Video: IP vs Analog Tutorial explains this in even more depth]

HD-SDI is the 'grand daddy' of them all. It is a real standard (SMPTE 292M). It's been around for a long time, there are handful of surveillance products supporting. Adoption has been minimal because pricing has been high (at or above IP camera levels) and support has been limited.

HDcctv 1.0 is HD-SDI with compliance testing by a one man alliance. It suffers from the same problems as HD-SDI and has the same limited adoption. Both of these likely have little future.

HD CVI is from Dahua. It is an HD analog technology that offers longer distances and adds bi-directional control relative to HD-SDI. Dahua has lots of OEMs.

OEMs: Many of those OEMs, to make themselves look more original, have hid their use of HD CVI and created their own terms. Examples include IC Realtime (HD-AVS), QSee (AnalogHD) and FLIR (HD MPX). In fairness, Dahua invests little in marketing so most people do not know what HD CVI is.

The main plus of HD CVI is that it is very low cost, far less than HD-SDI and IP. IPVM expects this to drive significant adoption. See Testing HDCVI and Testing Q-See HD CVI kit.

HDcctv 2.0 is Dahua HD-CVI. HDcctv 2.0 is also incompatible with HD-SDI and HDcctv 1.0. Got it?

HD-TVI is, or soon will be, from Hikvision, though Hikvision will not publicly confirm it (see: Hikvision HDTVI - Dahua HD CVI Competitor?). From what we have learned, HD-TVI will not be compatible with any of these other technologies above. Also, since Hikvision has many OEMs as well, there is likely to be many other labelling / names for them.

In sum, there are 3 camps, each of which are incompatible with the others:

  • HD-SDI / HD-cctv - likely to die out, little adoption
  • HD-CVI - from Dahua, gaining ground rapidly because of super low prices, with lots of OEMs changing names
  • HD-TVI - soon to come out from Hikvision, likely to be similar in price / positioning to HD-CVI

A Standard Possible?

You might note that IP cameras had a similar issue years ago, which lead to the much loved / hated ONVIF 'standard'.

This is more difficult with the non-IP versions as they typically require different hardware to encode / interface with each protocol / signal. There are a few attempts at building DVRs with physical interfaces to multiple non-HD versions (as well as analog) but it will require buying new equipment and at greater expense.


Ask away.

When it comes to these analog 'HD' transmission standards, is there a limit on camera resolution?

Can it go higher than 1080p like IP can, to 5MP or even higher?

Theorertically they could go as high as any IP camera. In essence, someone could come up with a standard that really was just IP over coax with some magic to auto-address cameras. In fact, *ethernet* and *IP* are two different things, and on a plug and play closed network you could drop IP and just do Ethernet networking and save a little bit of packet overhead.

Underneath it all, it's really just electrical pulses on a wire.

There is nothing technical preventing these HD-* offerings from meeting or exceeding IP resolutions. HDcctv has (or had) this problem because it was derived from an SMPTE (TV studio) standard, so HDcctv was limited to the max commonly used TV resolution. HDcctv/SMTPE *could* also go higher, but you'd have to wait for the general broadcast market to generate enough demand for it to happen. That is (IMO) one of many things that made HDcctv unviable from the beginning.

In essence, someone could come up with a standard that really was just IP over coax...

Back in the day IP was always run over coax/ethernet stack (thinnet, thicknet), so that shouldn't be too hard.

But, that would be going back to packetized delivery, and that's certainly not the most efficient way to stuff a pipe! Although as John points out the hardware would have to change, just increasing the carrier frequency of the synchronous transmission (analog or digital), will allow more information (pixels) to be transmitted.

On the other hand A asked:

When it comes to these analog 'HD' transmission standards, is there a limit on camera resolution?

I think the most accurate statement would be: Yes the limit of the standard is 1080P, because the transceiver hardware is designed around that flow rate, in the same way that NTSC was constrained. Though that is not the limit of non-ip coax.

SMPTE will most likely up the transmission frequency as it has in the past for 4k. CVI can do the same. IP doesn't need to do anything because it is not tied to some arbitrary pixel flow rate. That is a big advantage of packetized network delivery, though because of the overhead involved it ultimately means less usable data on the pipe. Analog transmission, contrary to what you might have heard, allows the highest usable(non-overhead) data rates. More of the pulses on the wire correspond directly to the data you are trying to communicate, and less about where its going and whether its error-free or not and how to re-assemble it later...

Rukmini, you have a knack for writing a lot of words and taking conversations off-topic.

There is no practical reason why HD-* transmission mechanisms couldn't match the resolutions available from cameras using IP transmission. None. Zero.

However, we're unlikely to see a 16MP HD-* camera anything soon because the market demand isn't there. These architectures seem to be targeting the lower camera count budget-conscious buyers, which are also not the typical high-demand user.

We can get into signalling methods and efficiencies of different encoding mechanisms, but none of that would matter. HD-* can match IP for resolution if it wants to. However, you're unlikely to see much more than 1080p on SMPTE-based systems because SMPTE seems to prefer an optical carrier for the higher-res stuff.

When it comes to these analog 'HD' transmission standards, is there a limit on camera resolution?

IMHO, your answer of:

Theorertically they could go as high as any IP camera.

is misleading, since I believe the correct answer is, "These standards are limited to 1080P". Sorry for the fluff. :)

Which standards are limited?

What data do you have that backs that statement up?

From the Dahua HDCVI Intro page:

What is HDCVI? HDCVI is a solution for megapixel high definition applications, featuring non-latent long-distance transmission at a lower cost. The name has to do with its baseband and quadrature amplitude modulation technology, which is able to avoid CVBS cross talk, completely separate brightness and hue signal, and further enhances video quality. The HDCVI solution incorporates both cameras and DVRs. The system is star topology structured — the DVR serves as a node for an over coax P2P (Point-to-Point) transmission to the camera. Thetechnology offers two specifications: 1080p (1920×1080) and 720p (1280×720). In addition, the technology features the Auto Signal Compensation (ASC) patent, which only allows an extremely low signal distortion along long-distance transmissions.

Now that I have done as you requested, I would ask that you drop the anonymous ad-hominem attacks and instead re-examine the original question at hand:

When it comes to these analog 'HD' transmission standards, is there a limit on camera resolution? Can it go higher than 1080p like IP can, to 5MP or even higher?

I think key is the 'like IP can' statement. Packetized networks break things into packets, big packets, little packets. All the packets can go a different way, arrive at different times, it doesn't matter. It's an asynchronous proccess.

HDCVI is fundementally different; it is a protocol that only has 2 "size" boxes, 1080 and 720, and only one size at a time. HDCVI was a protocol that was written with HDTV video in mind. It's HARD-CODED for it. To make it carry more information one would have to change the frequency or the encoding method. But then all existing hardware breaks.

Contrast that to IP where one can continue to pile on higher resolutions and higher resolutions (to a degree) because its application layer (video) is not tied directly to it's transport and network layers.

Do you believe NTSC is limited? Because in the same way that NTSC is limited, HDCVI is also, it is a synchronous analog modulation, (QAM), of uncompressed video, at a fixed carrier frequency in a standard format (CVBS).

Finally you write:

There is no practical reason why HD-* transmission mechanisms couldn't match the resolutions available from cameras using IP transmission. None. Zero.

But if you mean 'as they exist today', IMHO, you are simply mistaken. If you mean in the future thru modification of the transmission frequency or encoding, then you are correct but then I believe you are mistaken about what the question was.

First off, you only provided a reponse on HD-CVI, whereas I was talking about the HD Video-over-coax-without-IP concepts in general.

The OP of this thread seemed to be asking THAT question, they did not specify any particular format, but called it 'HD' transmission standards and asked about resolution limits as it relates to IP cameras.

There is no reason they can't scale to higher resolutions.

You still have not disproven that, you've only provided a lot of words about what exists TODAY. HDCVI may only have 2 "size" boxes today, but it's also basically a standard made-up entirely by Dahua. It can be whatever they want it to be. Like HDcctv, we could see an HD-CVI 2.0 with 27 "size" boxes, but totally incompatible with today's "standard". The point being that piece of coax cable is fully capable of carrying a higher resolution video signal without having to resort to IP or packetization. Or, maybe it resorts to packetization but does NOT use IP.

You also don't appear to know any of the real technical particulars underlying HDCVI, only what Dahua posted on their page. Dahua is one of the largest camera OEM's in the market. They sell millions of cameras, including ones above 1080p resolution. I think they have a pretty good view of the cctv camera market and where things are going. Do you think they created this recent protocol and specifically limited it to 1080p with no thought of future-proofing it in some way?

Rukmini, are you willing to bet that we'll never see a 3MP+ "HDCVI" product released?

Stop it. This is obviously increasingly personal for the two of you.

We all agree that, at some point in the future, there will likely be higher than 1080p HD non-IP over coax offerings.

We also all agree that it is not now, and that when it comes it will need new hardware on the receiving side.

If anyone has any specific product roadmap knowledge on future releases, please share. Otherwise, discontinue this line of discussion.

John, if I may be permitted to briefly post a last time, I would like to say that despite appearances, B and I have actually been in agreement on the main point of the plentiful and latent capabilities for this type of bespoke technology, as evidenced by my 'Analog Transmission' statement in my first post. If anything we only differed on what the original questioner was asking, in which my opinion is no more valid than anyone elses.

Finally I would like to thank B for giving me the impetus to research the subject matter thoroughly, as I certainly have gained from it, as I hope B has. :)

"Are you willing to bet that we'll never see a 3MP+ HDCVI product?"

If it's open to anyone, I'll take the bet. Since your camera will be HDCVI, then we can use my brand new HDCVI DVR to make sure it really is HDCVI. Ok?

But to be fair, I will offer the same bet, to test the next new, never seen before resolution, IP camera on your tcpip network, just to make sure it really is IP. Ok?

HDcctv 4k! To be released in 2024!

As Manufacuter B says, it can be done theoretically, but it would require new hardware on both sides.

As a practical matter, it appears 1080p is the practical max for any of these technologies for the foreseeable future.

"As a practical matter, it appears 1080p is the practical max for any of these technologies for the foreseeable future."

Agreed (obviously) :) The limitation is not technical as much as it is market demand/budget driven.

"HDcctv 2.0 is Dahua HD-CVI. HDcctv 2.0 is also incompatible with HD-SDI and HDcctv 1.0."

Seriously? Does Todd know this, LOL?

How do you think Todd stayed 'in business'? The original alliance founders abandoned him so Dahua was the replacement. In exchange for sponsoring the alliance, they got their technology 'standardized.' See: The HDcctv Shakeup

I saw that article but this is the first time I heard that HDcctv 2.0 = HDCVI. That basically kills the HDcctv Alliance since Todd has constantly claimed both the unique attributes of HDcctv and its total backward compatibility.

I have to wonder what Dahua management thinks they are getting for the money. HDCVI can likely stand on its own and wouldn't have all of the baggage associated with Todd and HDcctv.

HDcctv 2.0 AT is Dahua HD CVI. See Dahua praise it:

"Yin Jun, Dahua's Director of R&D, said: "We're very excited about HDcctv 2.0 and the potential for flexibility it offers both end users and installers. HDcctv 2.0 AT, in particular, provides the means to upgrade any analogue system to HD quality video with remote control without disturbing the legacy infrastructure."

There's a second HDcctv 2.0 standard, called NR, evidently for not relevant...

As for why Dahua did it? My guess is they know little about the Western market and saw it as a relatively low cost way to buy some marketing.

Btw, people at Dahua read IPVM so feel free to pass them your thoughts ;)

My thoughts? Hmmmmm...

To Dahua,

I have no particular bias against any of the HD Technologies - HD-SDI, HDcctv, HDCVI, etc., except I have to comment that all of these "HD" acronyms must give many in our industry a serious headache. How do the proponents of each technology differentiate themselves from one another? Even the names are confusing, let alone the features and capabilities of each.

As to the HDcctv Alliance, Dahua has seriously hitched themselves to the wrong star. I know Mr. Rockoff can be very convincing but as others have better stated: "He is known for his myopic vision, intolerance, rhetoric and bombast..." and "He is the most condescending man in CCTV."

HDCVI would likely succeed or fail on its own merits with or without Mr. Rockoff but with him, you are guaranteed not to win many friends. Better to make a name for yourselves, which apparently you are already doing as evidenced by positive comments on your products both here and on other forums where I participate.

I would bet if you asked previous members of the HDcctv Alliance steering committee, at least some would likely say privately that they wished they had never heard the name Todd Rockoff.

I checked out the HDcctv Alliance website for the first time today. I was surprised to see that HDcctv 2.0 also includes HD-SDI (HDcctv 2.0 DT) and is backward compatible to HDcctv 1.0. Here is the HDcctv Alliance specification link. Was this not up a couple months ago? I also notice you said "NR" instead of DT above.

"HDcctv DT 2.0TM adds plug 'n' play remote control to the underlying HD-SDI-style transmission"

"HDcctv DT 2.0 products are fully backward-compatible with HDcctv 1.0 products. HDcctv DT 2.0 transmits bit-perfect HDTV signals over the same cable distances as HDcctv 1.0"


Thanks for the feedback.

Earlier this year they were calling it NR (e.g., 1). Evidently, it's now been switched to DT, presumably for digital transmission.

It's not clear to me who is supporting 'DT' as Dahua CVI is 'AT' and the products we see shipping.


I was just in a conversation with some analog installers. Their analog suppliers have been pushing HD-SDI on them. Both are stating that if a customer’s old school dvr goes out, you can just replace it with an HD-SDI dvr as the dvr can recognize if it is an analog camera, HD-SDI camera, IP camera, 960H camera, the latest HD-SDI 2.0 camera and a few more old school HD analog solutions (Plug-n-play) instead of replacing the whole surveillance solution.

They're also saying that the suppliers are stating they are staying away from CVI and the upcoming TVI as they are proprietary... as of now. I guess both suppliers state that CVI still has many problems and it does not work as far (length) as they say it will. They also say that CVI only goes to 720mp no matter what Dahua claims. The suppliers did tell them they are hearing rumors that TVI is looking great in tests compared to CVI.

I was thinking hardly anyone had any HD-SDI or other HD-Analog cams. After that conversation, I think there might be a niche market out there where there are many HD-Analog cams. I'm guessing this niche market includes very small businesses and large homes and that is where these installers make their living.

Can a HD-SDI dvr really detect, on plugin, the type of camera that is connecting to it and auto adjust? It does not sound like the Tribid dvr mentioned lower in the comments.

I don't know about the DVR question, but as far as CVI only doing 720p, that's wrong. We have in hand 1080p cameras and DVRs, and they quite clearly produce 1080p video.

We've also tested 1080p and 720p HD-CVI over a 1000' spool of RG-59 with connectors barely crimped on, then through 1000' of UTP with baluns, and it worked fine in both instances.

And while Dahua developed HD-CVI, HD-TVI is using third-party chips, not Hikvision's own. There are already several brands selling TVI cameras.

Long story short, their supplier is trying to push them to HD-SDI.

There are already several brands selling TVI cameras.

Do you know any selling TVI DVRs though? I ordered 3 TVI (or mis-labeled CVI) cameras yesterday from Securexpress only to find there were no TVI dvrs available...(nor native TVI monitors) I pulled the trigger anyway, so...

There's a lot of low end suppliers jockeying here and surely much of their claims should be taken with a grain of salt.

For example:

"Replace it with an HD-SDI dvr as the dvr can recognize if it is an analog camera, HD-SDI camera, IP camera, 960H camera, the latest HD-SDI 2.0 camera and a few more old school HD analog solutions"

First, what's shipping today with HD-SDI DVRs is almost always HD-SDI only. No NTSC, no 960H, no SDI 2.0, etc. Conceivably one could build a hardware solution that auto detects and includes the electronics to handle all these different coaxial inputs but that is going to be far more expensive, even if feasible. There are a few that can do analog + one coax HD input but that's the max offered.

By contrast, here's Q-See's warning on their HD-SDI series:

Depending upon the model, your DVR is equipped to work with conventional analog cameras or digital high definition SDI (Serial Digital Interface) cameras. Both cameras use similar cables and connectors, (see Section 2.5 for connection instructions) but they are not interchangeable as they are two completely different - and incompatible - technologies. If you are adding cameras beyond those that came packaged with your DVR, be sure to check that they are compatible with your system."

Quite frankly, part of the problem with this segment of the market is that it attracts a lot of shady operators that do not know much about technology. Specifically, I am referring to the middleman / dealers, not integrators.

I see this company makes a DVR (I would call a server) that takes SDI, IP, and Analog with a lot more channels than the current Tribid recorder from Dahua. I wonder if this is plug-n-play or if it needs to be configured manually.

Spec Link

They are using an off the shelf Geovision GV-SDI-04 card. On Geovision's site, it is listed under HD-SDI and does not make any explicit claim of supporting traditional analog cameras. It might but usually if such a feature was supported, they'd explicitly tout it.

The online price of that 4 camera capture card is $700 so even if you can do both that's $2,800 for a 16 camera recorder, excluding the actual machine and storage.

Compare to a 16 channel Dahua tri-brid, including machine, for $999. Note that this one supports CVI, analog and IP but not SDI.

In addition the PC-GVHD4 can also be built as a hybrid recorder that supports HD-SDI cameras, traditional non-HD analog CCTV cameras, and network IP cameras

(1) You are quoting from the online retailer, not Geovision.

(2) They may mean you "can" buy a different Geovision non-HD analog CCTV capture card for those and mix and match it in a single machine. This would work but does not mean the GV-SDI-04 can.

Even if it can do this, it remains expensive and cannot support CVI, TVI, AHD, etc.

This would work but does not mean the GV-SDI-04 can.

No one claimed it would. John, look back Jeremiah said

I see this company makes a DVR (I would call a server) that takes SDI, IP, and Analog...

He linked to the online reseller only. He didn't mention the GV-SDI-04 card. He didn't even mention Geovision.

Undisclosed decided to focus on the Geovision card's capability, or lack of. He then said the Geovision card did not support Analog. If Undisclosed's point was that this system would be expensive once built then he could have said that. I was just showing where the Analog claim came from, so at least people could understand.

Even if it can do this, it remains expensive and cannot support CVI, TVI, AHD, etc.

The comparison is between Dahua Tribrid and the Boughton Tribrid. Are you saying the Dahua supports TVI, AHD? The Dahua doesn't support SDI, and the Boughton doesn't support CVI. Tri=Tri


The server/PC/DVR/machine is predicated on what Geovision can do. That's why I highlight it.

A number of companies offer Tri-brid, typically at a distinctly higher price and none of them offer multiple HD over coax technologies. In other words, pick only one of SDI, CVI, TVI or AHD.

This might change in the future if they build in the electronics to detect and encode both but this is what is the reality today.


Yes, at this moment in time, HD-SDI does have the sales number advantage over HDCVI, HD-TVI and AHD. That's primarily because it has been around for at least 5-6 years. That said, it has some very clear disadvantages like limited range, limited transport options, high equipment prices and lack of support by major manufacturers and almost every VMS.

HDCVI is a relative upstart and HD-TVI is just barely entering the market, while AHD isn't even that far along.

I believe that HD-SDI has pretty much peaked in sales. Heck, even Todd Rockoff is starting to acknowledge it is dying. In a LinkedIn Discussion just today he stated "I expect that most surveillance customers would agree with you that the analogue HD tech has the edge on vanilla SDI because of the convenience advantage you cite: Analogue HD works (to some extent) over any legacy cabling, whereas SDI demands broadcast TV studio quality infrastructure."

until you cannot connect up to 24 cameras to the recording server by one cable and a switch, this is a good alternative but will not replace IP cameras.

The HD-TVI chipset is from an independent company so it is not proprietary or controlled by Hikvision. This makes it somewhat more "Open System". It is limited to 1080p today. I do not know the roadmap above 1080p. It is not compatible with HD-CVI.

Do you by any chance have the name of the chipset provider?

Is there any other companies than Hikvision comming out with HD-TVI equipment that you know of?

I think an important point being ignored in this discussion of whether HDxxx can or cannot provide resolutions beyond 1080p is the market. I don't see higher resolutions being more than a small fraction of sales for a long time. Although IP cameras can provide almost infinite choices, there are severe constraints on frame rate and bit rate and the vast majority of applications don't need higher resolutions.

Never mind what is possible, it's what is practical that matters.

It probably got lost in all the back and forth above, but that's what I was trying to say with the following statement:

"However, we're unlikely to see a 16MP HD-* camera anything soon because the market demand isn't there."

(using 16MP as a slightly extreme example).

Carl, I agree that 1080p (or lower) will be the bulk of the market for, at least, a number of years to come, so max resolution is not a huge problem.

However, there are benefits to multi-imager, fisheye and higher resolution for special applications / spots.

This is why I think these HDxxx technologies would work best for the professional market with HDxxx encoders, instead of recorders. Hikvision and Dahua do not offer great VMSes anyway. And those HDxxx DVRs are really just encoders with VMS software and hard drives loaded in. Drop those out, add in an ONVIF Profile S output for the encoder. Then add them to VMSes like Milestone that now only charge a single license for an IP address and you have a super cheap encoder plus a super cheap professional VMS software.

This is why I think these HDxxx technologies would work best for the professional market with HDxxx encoders, instead of recorders. Hikvision and Dahua do not offer great VMSes anyway. And those HDxxx DVRs are really just encoders with VMS software and hard drives loaded in. Drop those out, add in an ONVIF Profile S output for the encoder. Then add them to VMSes like Milestone that now only charge a single license for an IP address and you have a super cheap encoder plus a super cheap professional VMS software.

If only there was a megapixel over coax solution that did have a Onvif Profile S encoder, and could be integrated into Milestone, Exacq and Genetec and would work alongside IP cameras as well? hmmmm, I'm sure there was something out there.

From experience I have found that the major NVR platforms will charge a license per camera and not per IP. This is understandable as they need to protect themselves, as the technology for multiple megapixel encoders/recievers is moving quickly and we will soon see 16 channel encoders/recievers. That is a lot of licenses to lose!

I agree with you both. That is why we chose IP cameras for HD instead of considering alternative(s) with our recent system upgrade. No one made (nor do they now, from my determinations) ONVIF-compliant encoders for the various flavors of HD. Nor, for that matter, for 960H or its extensions.

That has also been a major bone of contention between Todd and me - HDcctv could not be deployed in our vertical because it is aimed at DVRs, which are typically used for much smaller systems.

My post was meant to be a little bit sarcastic, as I think the original post neglects to mention the technology that I have talking about and has been mentioned on these boards once or twice.

Having an ONVIF compliant encoder is a very important feature, as it means the technology can be used alongside (or instead of) IP cameras on major NVR platforms.

Benjamin, thank for not promoting your product. For reference of others, Benjamin is alluding to StarDot Multi-Channel Long Distance Coaxial (MCLDC).

The big differentiator here is price. The Daua HDCVI equipment is literally 75% (or more) less expensive that StarDot MCLDC (or for that matter most even 'budget' big brand IP camera offerings).

I don't see the coax aspect of this technology to be as disruptive as the super low cost unit price for the equipment.

Well, with the Dahua Tribrid DVR, you aren't forced into one flavor. You can mix and match between 960H, HD-CVI, and IP (ONVIF). They have a few different models of the Tribrid coming soon. I have been trying to get my hands on some, but it doesn't look like ANYONE has any stock yet.

Dahua tribrid does not support HD-SDI, HDcctv 1.0 or HD-TVI, correct?

I am not criticizing. I am just emphasizing the point that interoperability across all these non-IP HD variants remains a practical issue.


That would be my guess as well. I just wanted to point out that Dahua did maintain interoperatibility between analog-SD, analog-HD (HD-CVI only), and IP (ONVIF). I made this point to show that if you did have a need for cost effective WDR (HD-CVI is missing a WDR option for now), then you could use an analog-SD WDR cam for that. Or, if you had an existing ONVIF IP cam, you could integrate that as well.

Let's be frank about HD-SDI or HDcctv 1.0, it is about as irrelevant as a 20 year old VHS time lapse system. Sure, someone is still probably using one, but that doesn't mean it's a good idea.

Jon, agreed. The main challenge is that you have to use Dahua VMS / recording software, which is lagging.

That's why I think there's a lot of value in Dahua doing an ONVIF supported HD-CVI encoder so you can then connect into any VMS you want.


That is our one complaint with Dahua as well. PSS just isn't up to par with other VMS software. However, their DMSS apps are quite great. We haven't seen another mobile app that comes close. In the small to medium sized market, this is a must. Most of our small retail installs use the mobile app more than any other method to view their cameras.

Also, I don't think HDCVI was meant to scale to larger installs. It is a SOHO style product IMO. It probably won't have wide acceptance in enterprise environments. I'm not sure you will see HDCVI encoders any time soon. But, if Dahua wants to serve that market with HDCVI, they better get an encoder quickly.

But, if Dahua wants to serve that market with HDCVI, they better get an encoder quickly.

Jon, can you explain a little more why that is the case? I can't think why you would want to use an encoder on an HDCVI camera as an initial strategy? Wouldn't Dahua just sell their equivalent IP camera in that case instead? I can see if you had HDCVI already and were migrating away from it to towards IP.


My point is that if Dahua wants to extend HDCVI into the corporate world, they are more likely to do so with an encoder solution. There is less likelyhood of them developing a VMS that would surplant an existing VMS. They are, first and foremost, a hardware dev. Sure, they do make some software, but it isn't very useful, other than the prementioned mobile apps.

As a counterpoint, you can use their DVRs as a quasi-encoder if you choose to. They offer RTSP feeds for each channel. It would be possible, but probably not very easy to manage, or cost effective.

As for why they would want to sell the HDCVI models over their IP models, I would assume because of the great delta between the two in terms of MSRP would allow them to have a great deal of advantage over traditional IP only mfgs. That is, unless, the cost of the encoder is equal to, or more than, the delta between HDCVI and IP.

The other major sticking point at the moment is a severe lack of camera choice in the Dahua HDCVI lineup. They don't currently have any varifocal options. They don't currently have any WDR options. Those are some major issues getting HDCVI into the mainstream corporate market. Sure the small mom and pop stores might be fine with fixed lenses without WDR, but not more savvy buyers.

Until an encoder, varifocal, and WDR are added to the HDCVI pot, I don't see it being viable for more than your shoppers club market. It doesn't mean it doesn't have value, just that it is limited as such.

As a counterpoint, you can use their DVRs as a quasi-encoder if you choose to. They offer RTSP feeds for each channel. It would be possible, but probably not very easy to manage, or cost effective.

Why not cost effective? 16 channel HD quasi-encoder for $500 is ~$35/ch?

The otherway into VMSes would be thru capture cards, no?


If they can supply a 16CH DVR, which has a larger chassis, SATA controller, video outputs, etc for sub $500, don't you think they could reduce the components down and make it even less expensive? I could see them offering an encoder for half that cost.

And, the $35/CH doesn't get you the functionality of a true encoder or IP camera. It lands you beneath both in terms of features and managment. I don't think many enterprise customers want to "duct tape" a DVR/VMS solution like that, unless they could control the cameras directly, which the DVR can only manage. So in effect, you are adding to the managment duties.

I think that the MSRP delta right now is about $60 between 720p HDCVI and IP. So, if they can manage to get an encoder at even the $35/CH that the DVR costs, you have a net savings of $25/CH. Also, if your VMS only requires one license per encoder, then you can see larger savings as well.

But, it all starts and ends with an encoder IMO.

I agree totally on the management hassle. I was just pointing out that the cost of your qdvr solution in terms of just hardware is peanuts/per channel, although as you say it is still severely deficient as an enterprise solution.

I am just thinking that it seems to get rid of most of the technical benefits of HD-CVI when you encode before you are at the DVR, no?

Leaving aside possible software licensing benefits, what's your feeling on what's cheaper today in the SD world? 8 SD IP cameras or 8 SD Analog and a 8 SD encoder together, (same quality) I don't know the answer, but I would think it would be the same equation for HDCVI, agree?


I never saw a purpose of SD-IP to be honest. Maybe I came along after it had a purpose? So, to be honest, I wouldn't be a proponent of SD-IP. I don't really see much of a benefit for HDSDI in the enterprise either.

i thought of one other cost involved with IP that we didn't factor, and that is switch ports. Obviously, IP would consume more ports, but both should consume the same total bandwidth.

But, unless an encoder allowed complete control of the camera (OSD, PTZ, etc), then I don't see it widely adopted in the enterprise.

Trunkslammers will LOVE it tho!

Btw, there's now AHD, which appears to be a Korean chip manufacturers alternative to all of the above. I don't think it's promising but it's starting to be marketed.

We have now been testing some on both Dahua's and Hikvision's analogue HD. It has been very interesting.

Our expereince so far is that Hikvision's HD-TVI is technically better regarding image quality and latency. In Dahua's solution we have seen artifacts similar to compression artifacts on IP cameras. This is not visible on the HD-TVI we are testing. Also the latency in the HD-TVI is around 100ms compared to slightly over 200ms for the HD-CVI cameras we are comparing with. This is tested in the same manner on both.

Any chance of IPVM doing a comparission between the two?

Yes, we are going to do a comparison. HDTVI is scheduled to be available in the US next month (September).

Btw, how are you testing latency at that level of precision? Is this after its been encoded or straight to a monitor?

Our test setup is quite simple. We have the camera connected to a DVR. The DVR has HDMI output.

We then point the camera to a clock with millisecond precision placed on the side of the monitor. We then record that. When plying back the recording we pause at number of spots and check the delay between the clock and the image of the clock on the monitor. We kan then see the "end to end" delay on a fairly accurate basis.

So this is encoded H.264 video then? i.e., "when playing back the recording"

The recording where we check the latency is H.264, but the stream that is recoded is just converted from HD-CVI/HD-TVI to HDMI.

I hope that clarified a bit.

So are you manually stopping the clock and comparing it to what the camera is displaying? I'm confused how you stop everything at once.


That's the same way we tested encoder latency in 2012/2013. We pointed an analog camera at a cell phone stopwatch, fed that camera to an encoder, brought that encoder channel up on a monitor and pointed another camera at both the stopwatch and the monitor and recorded its output.

In my mind, that's a valid way to measure latency since the second camera is simultaneously seeing both the "Live" stopwatch and the same stopwatch fed through the encoder. The first camera's signal is not measured through a "record/playback" cycle by the second camera - it is looking at the "Live" feed.

Thanks Carl,

A much better explenation than I managed.

Ok, I'm not saying that's not a valid method, I was just trying to confirm that's how it was being done!


Hi Etahn,

We record both the clock on the phone and the streamed video on the monitor at the same time.

When the test is complete we then pause the recording whenever we want and note down the delta between what is displayd on the phone and on the screen.(Or do a snapshot as i posted above)

Agree with D. From an old thread. (Reformatted for clarity)

  • Dedicate a ipad or smartphone to being a digital timepiece (many free apps) because some accuracy is helpful.
  • Position the smartphone so that it leans up against the side bezel of your VMS monitor.
  • Have the cam pointed at smartphone (with the stopwatch running) as well as the live VMS output, avoid feedback by angling cam.
  • Use a digital camera to take a picture of the stopwatch phone and VMS ouput screen in the same frame.
  • Subtract the times in the photo to get an accurate total lag time.

Delat between clock and displayed clock

Illustration of test setup wit mobile phone clock, precision 1/100th of a second

Interesting. The Devil's Advocate, in an interview with Todd Rockoff in the August issue of Benchmark Magazine, also noted excessive latency in HDCVI equipment on display at a Security Exhibition (undisclosed venue). Todd, as usual, glossed it over:

  • Devil's Advocate: The video has obvious latency. If it's being sold as zero latency, it should deliver that.
  • Todd: Are you asserting that CVI transmission is the reason for the latency or that it's the matrix inside the DVR?
  • Devil's Advocate: When someone buys a system, they don’t buy the local transport technology separately from any other part of the recorder. They buy a device that does something, and when one of the selling points is zero latency it must deliver that.
  • Todd: We have a different definition of terms.... This is a zero generation tribrid HDCVI DVR, and it does have some latency, but that's not intrinsic to the technology. In a year it should be right.

So, the question in my mind is: Is the latency coming from the camera or the DVR?

Any plans to test StarDot's coaxial technology John?

No, for 2 reasons.

(1) Tiny market share:

  • Hikvision's revenue: $1700 million
  • Dahua's revenue: $850 million
  • StarDot's revenue: $10 million ?

(2) High prices. Dahua is nearly giving away HDCVI cameras at sub $50 end user pricing. Stardot is ~6x that.

We will reconsider if StarDot starts gaining major traction, or the price comes way down, or other larger manufacturers adopt the technology.

So market share is more important than the technology?

Not quite 6x, you would find our coax cameras are around the $400 mark. It is definitely not as cheap as $50 a camera, but US Engineering and US based technical support does cost a little bit more that it does in Asia.

It is quite dissapointing to hear that our technology is being disregarded simply because we cannot compete with the influx of cheaper foreign imports.

Price does matter. And so does market share.

Especially when the price is 80% less and the market share is 8,000% more.

That's just the reality. You either offer lower cost or you provide more value. Stardot is, unfortunately, stuck in the middle.

Price is important, but low prices do not always mean good value (higher prices don't guarantee good value either).

I appreciate your input, I just want to point out that our products do have some valuable features. StarDot coax cameras transmit on much longer lengths of cable than the competition, and multiple cameras can be connected to a single coax cable (adding more value to an existing coax infrastructure). Not having to pull cable for each individual camera surely adds value to this product line, I'm sure an integrator that has ever tried to pull new cable through a packed conduit would agree.

And if Axis adds that technology, we'll buy one as soon as it comes out and test it.

Because what this is an incremental feature / advantage, and for things like that to gain broad traction, it needs to be from a company that has a strong position in the marketplace.

This may very well be good for StarDot's business but since it requires StarDot cameras to implement this and since StarDot has limited traction in the market, I do not see it as a mainstream offering.

Good info. Any chance you could post a pic of the compression-like artifact?

Because if it really is some sort of discrete-cosine macro-block marker then perhaps somehow you are viewing a dvr encoded-decoded stream (some kind of confidence monitoring?). That could account for the latency also. Though I agree its not too likely, so maybe the artifact is a variation of the moiree pattern? Its typically found when the luminance and chroma signals aren't fully separate.

Did you by any chance accidentally happen to try a TVI camera with a CVI dvr or vice versa? :)

Regarding your proposed death of HDSDI as a mode for HD over Coax, may I ask why would you abandon this technology for the exact same thing, with the exact same result, with untried, infant technology, never really used? At least Stardot stuff somhow connects a coax to an NVR, though I have not seen the bizzare connector that would do that, a 'BNC to RJ-45' I suppose. unless it gets converted, but I digress...

A simple amazon search for products to support your SDI system such as a converter, to jump a gap with a data bridge I presume, results in this:

1-16 of 794 results for "HD-SDI converter"

However, a search for a CVI converter results in this:

1 result for "cvi converter"

and sadly, the 1 device shown, is unrecognizable as useful in achieving the CVI to IP conversion.

A TVI search will point to a Mazda Protoge repair manual.

There is a simple explanation for this, there is a huge backbone of products for HD-SDI technology. I have not seen one compelling reason to abandon this technology.

Also, When I ask my supplier about the CVI and TVI, they forsee HDSDI as a strong and very useful HD over Coax solution. So am I wrong here? According to you, I am, according to my suppliers, I am not. Even the Pinnetron Onvif over coax never took off. Am I in the wrong place here? I am really not sure you are in the real world solutions realm for this arguement to have any traction.

Where would CVI trump an HD-SDI system in the real world?

I know you keep saying cost, but is a few dollars cheaper for a camera really worth it (rhetorical) when you have only a small handful of manufacturers making it, while tons of manufacturers are already making HD-SDI and also selling tons of HD-SDI. My gut says HD-SDI will always be viable.

I know you will want to eviscerate me on some or all of my points, and I also know that you guys are more knowlegable about this stuff than I, but I just have a different experience.


The HD-SDI converter Amazon search with 797 results is not related to surveillance. It's a 'converter' from SDI to HDMI, which is fine connecting to a TV, but does nothing for an IP video surveillance system.

I don't know any major surveillance manufacturers committed to HD-SDI cameras / recorders. Do you?

You have the IP manufacturers who are sticking with IP and now you have the two biggest manufacturers in the world (Hikvision and Dahua) committed to anti HD-SDI offerings.

I've seen this pattern over and over again. Without major manufacturers pushing a technology, it is destined to be a niche, at best.

If you are getting HD-SDI cameras at $50 a piece and can live with the shorter distance, no bi-directional control, no backing of a major surveillance manufacturer, that's fine.

But all of these limitations despite HD-SDI being around for a long is a bad sign for market potential.

Also, When I ask my supplier about the CVI and TVI, they forsee HDSDI as a strong and very useful HD over Coax solution.

Maybe you should ask them what they think of SDI, to find out what they forsee for CVI/TVI...;)

You're right about the back connectors - RJ-45/BNC, here's the front, here's the link.

My supplier told me they will have limited production of CVI as they dont see it as a successful market. Just as I thought.

Just as I thought.

That settles it then! CVI will be not successful while SDI shall be 'strong and useful'. Thank your supplier for the info.