Ip Cctv

[eoghanfla]

was just doing a bit of research on IP CCTV. Has anyone istalled any yet? The high def stuff looks impressive. Could this be the tape vs. CD of the CCTV industry?? IS the high def stuff really that clear???

Fla

[breff]

I've done some IP stuff, the problem is that the network administrator insisted on a certain amount of bandwith to be used even though the cameras were homerun to the servers. This meant a resolution of 640*480 and a frame rate of 6fps.

So at this setting it wasnt that great.

[HighRes]

Hi Guys

I am back after a short break and a change of Jobs. Any questions on Megapixel cameras just ask, I have tried the lot and have recently taken up the position as Sales Director for Avigilon who offer a range of multimegapixel IP cameras.

In response to the original question most of the High def IP cameras on the market are CMOS and this has associated disadvantages. CMOS scans accross the sensor so moving objects often experience motion blur, obviously with most incidents it is the moving part of the image which is important. Also as Breff pointed out often the high definition cameras are compressed down so much that the additional pixels offer no advantage over a traditional CCTV system. Even a full PAL CCTV image often starts life at 1244Kb but is compressed down to 5-30Kb by the DVR, IP systems mostly compress twice, once at the camera and again in the DVR so the final outcome is full of artefacts. CMOS cameras are also much less sensitive to light than CCD and as a result night time images are usually unusable.

Another thing to consider is that the vast majority of IP cameras come from companies with an IT background who have not experienced the last 30 years of camera development so often basics like back focus, auto Iris, Wide Dynamic range BLC, AGC etc are just not there.

Without wanting to make this too much of a plug, Avigilon offers a range of CCD megapixel cameras up to 16MP and we record these on our own servers using a lossless compression meaning that we can zoom into playback images digitally up to 50 times with no pixelisation and no Artefacts and still have the same resolution as a conventional CCD.

Lossless compression does use a lot of disk space but this is 2007 and Hard drives are no longer a premium. If quality is essential then so is lossless compresion and megapixel technology.

There is an interesting presentation at the following link

http://avigilon.com/presentations/overview.html

It has sound so turn your speakers on.

I hope this helps

All the best

Robin Hughes

[advancedprotection]

Hi Robin, very interesting . could you PM Me with an idea on prices please as i would get a lot of interest from existing customers

Thanks

Martin

[CameraGimp]

In response to the original question most of the High def IP cameras on the market are CMOS and this has associated disadvantages. CMOS scans accross the sensor so moving objects often experience motion blur, obviously with most incidents it is the moving part of the image which is important. Also as Breff pointed out often the high definition cameras are compressed down so much that the additional pixels offer no advantage over a traditional CCTV system. Even a full PAL CCTV image often starts life at 1244Kb but is compressed down to 5-30Kb by the DVR, IP systems mostly compress twice, once at the camera and again in the DVR so the final outcome is full of artefacts. CMOS cameras are also much less sensitive to light than CCD and as a result night time images are usually unusable.

Another thing to consider is that the vast majority of IP cameras come from companies with an IT background who have not experienced the last 30 years of camera development so often basics like back focus, auto Iris, Wide Dynamic range BLC, AGC etc are just not there.

Without wanting to make this too much of a plug, Avigilon offers a range of CCD megapixel cameras up to 16MP and we record these on our own servers using a lossless compression meaning that we can zoom into playback images digitally up to 50 times with no pixelisation and no Artefacts and still have the same resolution as a conventional CCD.

Pardon my ignorance but as you work for a camera company rather than an IT company and so your knowledge as well as your products are obviously better can you explain in a bit more detail what you mean when you say that CMOS scans across the sensor and this causes motion blur.

I always thought CCD's scanned across the image sensor. I would have thought image blur was a consequence of shutter speed or exposure time. Just thinking aloud.

Regards

The Gimpster.

[HighRes]

Thanks for the interest CG, it is important that people take an interest in the real technical differences as opposed to believing what the specsheets state. I know we are not the only folk on the forum who have an interest in restoring quality to the industry.

The key difference is that the progressive CCDs Avigilon use have a global electronic shutter. This allows us to expose the whole CCD simultaneously and then stop that exposure globally across the whole CCD so all pixels capture the same moment in time for the same length of time. If you want more technical details on this let me know.

By comparison many CMOS sensors have a rolling shutter where lines are exposed sequentially down the sensor. This means that the moment in time when 1 row collected light may not be the same as the moment in time when another collected light, even though they will both collect light for the same amount of time. This can cause a motion blur or distortion around moving objects that is independent of exposure time. There are CMOS sensors with global shutters (similar to what you get in a progressive scan CCD) available now as well but most (I think all in our industry but I may be wrong) still use rolling shutters that don

[Doktor Jon]

Ahhh the mists are clearing, Robin

So that's why you had an interest in their multi megapixel cameras

As a completely impartial observer I just thought I'd quickly mention that Avigilon have only just issued a press release in the States with the following ... "Frost & Sullivan recognized Avigilon with the 2007 North American Frost & Sullivan Award for Technology Innovation in recognition of its state-of-the-art High Definition Surveillance System."

They're supposed to be a tough bunch to impress, so obviously somethings being done right methinks

Good luck in your new position RH

[eoghanfla]

Thanks for your reply Robin. You have shed light on a very grey area. I think there is a big issue with old school installers and the new IT kids on the bloc. This technology is obviously the way forward but I fear there will be a lot of resentment. I have seen high end analogue/digital cctv and it is lacking the punch. I personally cant wait to get my teeth into a megapixel gigabit rig yum yum.. bye bye coax hello 4 pair heaven!!!!

Fla

obviuosly one of the young IT punks!!

!

[Alpat Systems]

We've installed quite a few IP based CCTV systems, in fact IP products now account for more than 70% of our work, which includes CCTV, IP based Multimedia systems, IT Services including VOIP.

I personally come from an IT background where I started in I.T support then Systems Integration and finally network consultant for one of the Large World Wide IT companies.

The I.P protocol has been around for years now (early 80's), yet it still amazes me the myths that people come up with.

I agree that bandwidth has always been a huge issue for IT professionals but with a good understanding of TCP/IP and common sense most people can get to grips with the basics.

We

[CameraGimp]

Firstly, I am all for the move away from conventional (PAL/NTSC) CCTV. It is about time we free ourselves from the restrictions of TV standards that were developed before I was born and that is a long time in both technology and dog years but I would be interested to hear your thoughts about what is an acceptable trade off between reduced frame rate versus the advantages of increased resolution?

To make this clear, mega pixels come at the cost of frame rate. In the last few years the world of digital recording has been pushing on us the value of higher frame rate recording so you can record every camera at full frame rate rather than multiplexed, where as we are also looking at a world where the camera may only take one picture a second, albeit at a very high resolution.

So where would you put the balance between increased resolution and acceptable frame rate.

This is I believe why conventional CCD's have not kept pace with digital still cameras. I have often wondered why the top of the range 1/2" camera only has 440K pixels whereas a