tesc_cctvpro

The response to our article was very interesting. Actually the entire gist of the article originated within an extremely price sensitive environment where DIY installs are the order of the day. The target market, intended consumer of the article was the DIY user - very few of these users focus on quality or service as a buying determinant - the majority focus on price almost exclusively. The assertions made in the article relate to cards being bought from ebay, and being installed into existing home computers by DIY users. The intended article objective - which is not effectively conveyed by quoting sections thereof - was to highlight the pitfalls, would be DIY users might face, and that in such circumstances a standalone DVR would be a better option. The challenge still stands, regarding manufacturers who sell direct to DIY users , via informal channels such as ebay, etc with the view to the item being installed by a DIY end user. Indeed, we are guilty of hyping and sales talk, which in effect is what the blog is about - it is interesting that some may have perceived it to be a news site. We do in fact encourage our corporate clients, with the luxury of an IT staff - to lean towards PC based systems. Motivationally - qualified IT staff would find it far more convenient to maintain and repair a PC based system than a standalone unit. Still enjoyed the various views expressed though, and as with everything - does inspire us to pay a little more attention to the perspectice and discernment position of potential readers.

One of my customers relates that a DVR, which they have seen, offers a function to connect an external hard drive via the serial port on the DVR. This feature allows the external hard drive to mirror the internal drive. (It is not a backup feature). The external drive can be accessed by the dvr as if it was internal, should the internal drive suffer malfunction. In South Africa theft and malicious damage of the DVR is common. Anybody know which dvr we are talking about ? Or another DVR which offers a redundancy feature like this?

Does anybody have any experience with the TVT DVR. I see that Qsee promotes their 23xxL series. Considering buying these, and they are sending me a free sample for testing. But would like to know if anybody has used them before.

Hi Halam, From the request i gather that your security needs are not really critical, seeing that you are looking for a cheap DVR. There are cheap and expensive dvr's. Just because something is expensive won't guarantee it is quality, but quality definitely never sells cheap. What do you want to achieve with this DVR?....I gather due to the D1 spec and high resolution camera required, you are looking for high end performance from a low value device - certainly vendors know the value of their product, they are the ones that decide what it's worth. When a vendor sells cheap - it's because he knows he has a low value product

Interesting comment on analog -- we moved all our analog system into the "legacy cctv" category on our website about 1 month ago.

Hmmm.... We did point this out to them and they started putting 4CIF in brackets where they mentioned D1. The explanation we have is that due to the limitations of CCD sizes in cameras, if DVR manufacturers where to provide full D1 resolution, there would be a grey area on either side of the image.

Forgive me for belaboring the point, but it is a very important one in our industry. This is what I have , D1 is 720x480 pixels 4CIF is 704x480 pixels DCIF is 528x320 pixels 2CIF is 704x240 pixels CIF is 352x240 pixels QCIF is 176x120 pixels Are these figures not correct?

Just for the record: D1 PAL: 720x576 D1 NTSC: 720x486 4CIF PAL : 704 x 576 4CIF NTSC 704 x 480 Regarding the difference between 5 & 25fps it all depends on the specific application and intent. Scientific studies have shown that the location of a users focus of attention does not significantly change given frame rates between 5 & 25fps suggesting that the selection of visual cues which defines a users area of interest is not adversely affected by frame rate variation. Very few users would discern the difference between 25 & 30fps. In any case the point was that 5fps may be suitable for some applications while 25fps might be for others -----i could hardly accept that every surveillance application demands 30fps temporal resolution.

As with all surveillance decisions the cost of a solution is weighed up against the criticality of the data. Given that the Data is not that important to you, using a standard HDD should not be a problem. I have also experienced specific compatability issues with WD drives in surveillance. Hard Drive errors are one of the most common to arise in a surveillance DVR. For every DVR hard drive that runs for 12 years (?), hundreds more fail prematurely . Seagate has specifically optimized their SV series HDD for surveillance, they specifically use the word surveillance. The SV series dvr can be customized for video or data payloads using the ATA-7 streaming command support. Surveillance hard drives are subjected to more writes and less reads than PC hard drives. Some reputable DVR manufacturers, such as bluestar have specifically worked with seagate in the development of the drives and have raised their warranties to 5 years on their hardware since adopting the SV drives. In addition studies have shown a 10% drop in energy consumption when using a SV drive compared to standard HDD. It is unrealistic to expect a HDD to last 12 years, but very realistic to assume that a hard drive installed in a surveillance dvr may fail prematurely. How significant "may fail" proves to be, depends on the criticality of the data.

Not really into debating with anyone - the above is from a peer reviewed paper examining the performance of H.264/AVC versus Jpeg2000. I merely offered the info in response to the question. We are all at liberty to choose what works best for us.

Have you tried another hard drive?. Hard drives are very sensitive to irregular power issues --- the key is that this occurred after a power cut!

It is unwise to use a standard desktop hard drive. Desktop harddrives are not designed for 24/7 cycling as experienced in a security dvr. We only use Seagate hard drives in our recorders and we use the SV model which is a Seagate Hard drive specifically designed for surveillance application. The hard drive is one of the most crucial components of a dvr, and yet so many people will just buy on price.....not very nice when the drive is inaccessible or corrupted at critical moments.

I have found that an H.264 DVR from a reputable manufacturer will just shade the Jpeg2000 on playback. Keep in mind that jpeg2000 is a still image wavelet coding standard, while H.264/AVC is a pure video coding standard.

I have no experience with this dvr but i would think that you need to go into the local machine and set up a user account and password , that user account needs to be assigned permissions for net access - likely. Many dvr's will not allow you to access them over the net with the default passwords, and require a user account to do so.

Indeed! many great points. Some manufacturers such as ours - dahua, have been developing h.264 for many years - there are others just jumping on the bandwagon. There is no standard regulating the encoder that is used to process H.264 and so you will get some really bad .264 DVR's- where motion is poorly managed. For instance the entire top half of a tree will blow in unison during wind, rather than individual branches and leaves, or people's faces are blurred during motion, even at close range. While I agree that no ordinary dvr will currently record the 600TVL, it is highly likely that the output of that 600 TVL camera is nowhere near 600TVL. If you are talking NTSC- i would be surprised if anything more than 330TVL comes out of that camera. The only benefit of a 600TVL rated camera in most instances is that you will be more likely to get the maximum resolution the dvr can record -480TVL. Sadly, those vendors who are quite happy to take your $100 for the camera won't tell you that it's basically worth as much as a 480TVL camera

Might as well second that seeing that intellicam is manufactured by my supplier Dahua. But let's look at the range. cost will depend on a few things: (1) Spatial Resolution - do you really need the highest level of resolution? remember high detail isn't really noticeable when you are observing whole scene's but does become important when you start needing to observe fine detail such as notes or writing. The dahua dvr provides 4CIf resolution on channel 1 for the 4-8 channel entry level units and the rest of the channels are standard CIF, on the 16 channel unit you will also get 4CIF on channel 9. Can you get by with high resolution on 2 channels and standard on the other? (2) Temporal Resolution: If you do need all channels at 4CIF, does it need to be real time. Most vendors hype up the real time issue, but in reality 5fps is adequate for a residential install, while most service stations are happy with 7fps. Casino's banks and cash points may spec real time 4CIF. The dahua DVR allows you to customize the frame rates on each channel. The difference between 5fps and 25fps is actually just fractions of a second. (3) Storage - machines come in 1U, 1.5U and 2U form factor - the larger forms having higher hard drive capacity. So determining the length of recording to be held is important. (4) Network. - The dahua machines offer dual streaming, which means you can optimize the network transmission on one stream without losing quality at the local machine. The Dahua DVR's offer entry level CIF realtime machines with selected 4CIF channels, moving up to the mid range which allows 4CIF on all channels around 12-15fps, and then into the top of the range model with full realtime 4CIF. By the way your $1K target is very doable - with the top of the range dahua 16 Channel at full 4CIF probably in the region of about $600. Check the above though as you may not actually need to spend that much.

It is not often that you are going to get the same quality of video over a network as at the local machine. If the dvr you are using doesn't have dual streaming facilty - a seperate stream for network, then even more so problematic. If there is a seperate stream facility for network then you need to reduce the bit rates and picture resolution settings. Network transmission is always a trade off between quality, speed and bandwidth capacity. Unfortunately too many vendors lead customers to believe you can just plug 16 cameras into a network and all is well - we have customers ask us to remove the cctv system from their corporate networks due to the effect the load has. H.264 compression is fine, but it comes with a premium on the client PC side as H.264 will require more processing power than the other network unfriendly codecs. Image quality can differ from monitor to monitor as well. Some monitors are just awful. usually we reccomend running CCTv video on a seperate parrallel network. Of course you just may have a poor DVR. Many people buy cheap and find that the product was well valued - low value that is

There are actually many reasons for security buyers to join a buying group. I used to run a general buying club called wholesalebuyersgroup. It was very effective untill it started to grow and the groups members started wanting too diverse a range of products. So I closed it down, as it took longer to decide what to buy than to actually do any business. The concept makes a lot more sense in a specific field such as security. We had people in china who actually facilitated each members payments to the supplier, received the products and then redistributed them to each member. It was the perfect wholesale purchasing solution for those who could not approach manufacturers directly and wanted lightbulk volumes at wholesale prices. If anybody is interested in establishing a similar setup for security DVR's and cameras let me know.

We buy directly from dahua. Mostly dahua sells oem. I am actually looking to form a buyers group so that I can bolster my volumes to keep dahua happy. Any security resellers and integrators are free to contact me as long as they aren't competing in my market. The idea is to consolidate our purchases. We are official distributors of Dahua in South Africa, so anybody who would like to piggyback on our purchasing is most welcome.

Hi all, If we accept that the maximum output for a NTSC camera is limited by the NTSC standard to 330TVL? What is the max output of a PAL camera?

All the DVR's in question are manufactured by Dahua technology. We market them under the original dahua brand so I could go on and write a biased review. Suffice to say that we and our customers are very happy with the quality and RMA of the device. I am just interested in your selection of camera? Why on earth would you pay for a 25m illumination infra-red camera, when it's only fitted with a 3.6mm lens. What is the target and target size which are trying to record, and how far away from the camera do you need to see? By the way -- if they say the camera has 25m illumination, you should work on about 10-12m outdoor. The camera is rated indoors, where there is plenty of reflective surface for the IR light to reflect off. Outdoors the IR light is going to dissipate into the night air, and will be reflecting off far less surface area than indoors, if you are trying to see 25m.

Hikvision is highly placed on the global A&S security listing with about $278m sales, Dahua jumped from 32 to 19 on that list, 2nd on sales volume in China with about $56m, and the 3rd manufacturer comes in at about no 48. My experience has been that if you go beyond the top3 manufacturers in any field in China, you are courting disaster, perhaps even beyond the top 2. Spelling is a huge issue, and the first point of contact that influences the end user. Nothing says cheap better than engrish! Unfortunately the lower down the scale you go the worse it gets. I don't believe that cheap is an excuse for "doesn't work properly", and what we are finding in the market is that many cheap dvr's appear to work very well -- until the end user finds that the dvr skips recording at crucial moments and can't send video over a network. All problems that are only discovered when you most need the back up video, or internet access. However I would be interested in what you find on your trip. I am busy looking for alternative brands as well. While i believe my current brand is excellent, the distribution loyalty leaves much to be desired. Chinese companies will leave you to invest vast sums in establishing their brands in a market, quietly and underhandedly supplying larger orders to some customers they siphon from you, and then in the growth phase, they will open the market to all your competitors - be careful of that. I am very interested in forming a consolidated global buying network. Collaborating with global security companies who wish to purchase light bulk volumes as a network from single suppliers -- so if you find something good, how about some feedback.

Unfortunately, these sort of issues and more are what most DIY consumers don't realize. If the security threat is such that your life, property, safety of loved ones is threatened, please get a professional security consultant to design and install your CCTV system. We cannot teach you on here all that a professional consultant would know. Firstly CCTV is a monitoring function, it is only one part of a security system. Unless you have dedicated person's watching the cameras, cctv will not detect anything or anyone. The PTZ and zoom cameras you describe are known as active surveillance devices, and are less effective than static cameras in detecting events. The PTZ will be useful for investigating an event, but who will do the investigating, and how will they be alerted to an event. video motion detection technology is a form of video intelligence, it is not free of false alarms . Just as beams and security PIR's are not free of false alarms either. All of these technologies are at best configured to achieve the lowest rate of false alarms. On a DVR - Dahua, you can select specific areas of an image to include or exclude from motion detection,You could actually design a virtual tripwire to activate recording. However, all of this is designed to create an alarm, a percentage of which will be false, the alarm alerts someone????? Who is that someone? Are they constantly monitoring the system? You can set the Dahua DVR to email you when an event occurrs. Where will you be when this happens? CCTV is then employed to investigate the alarm, to verify if it is a valid alarm, and then to initiate a response. These are all considerations you need to consider before discussing hardware. Who will be monitoring the security system, who will validate and investigate the alerts, who will respond to the alerts, Why, What, When, Where, How. CCTV is not a security system, it is part of a security system which performs the monitoring and investigation functions of a security system

Hi-Xman. We supply Dahua DVR's in South Africa. I have not used the iDVR software, neither skyvision. We tested Linovision some time ago, and although I really liked the linux concept, we had to send the software back to the drawing board. I believe it has come some way since then and they just sent me the latest version for testing - which I haven't got round to yet. We have supplied numerous DVR cards with the Digivision software, and the feedback has been all positive - given that I am no fan of PCI dvr cards. Mostly our customers looking for the text overlay feature of the Digivision/Netvision software will buy cards, the rest buy Standalone. So all i can say is that our customers have been very satisfied with the netvision software. Just be sure to use software from the original DVR Card vendor, as you may not be able to just download the software from netvision.

Given the 704 full screen width - many erroneously categorize their DVR's as D1, when they are actually 4CIF. Just a technicality, but one to be aware of in certain cases.