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PCI Bus Limitation - Resolution

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I have never seen the pci bus on a computer determine resolution on anything... I have seen resolutions based on what the camera supports and what the monitor you are using supports. That number doesn't fit the standard 4:3 ratio that a lot of things use... 640x480 does....

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iTS all about data, aint nothing out there using a PCI bus that can do massive data flow at larger resolutions, unless using hardware onboard compression, hence the new cards that have onboard compression!! they compress then send the data, no need for softwrae compression and it fits down the bus!

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for some cards I saw description different resolution for PAL and NTSC standart. maybe this is the case ?

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There are other limitations on image quality then the capture card. Cameras native resolution, lens quaility, ect. And you math is well off at least for some cards. At the software level we get three bytes per frame, not two. The digital stream is coming in as YUV or RGB vaules. So you get:

 

720*576*3*25= 29.66 Mbytes/sec per channel. Multiply that by 16 channels and you end up with 474 Mbytes/sec.

 

The reason for not using digital cameras is three fold. One is that no one has a standard interface. Even within the same company the cameras don't have a standard interface. So you have to code for each one. Second is that most digital cameras compress down to 320*240 or 640*480 to save bandwith over a network. And third, what format is the camera going to give you? JPEG? JPEG2000, RAW? The last one creates headaches because .RAW is just an extention, all raw file formats are differant on all of those high end cameras.

 

Other reasons not to grab stills. Unless you are taking a really rapid stream of stills, you will have time gaps of a second or two. If you are taking a rapid sersis of stills then you might as well be taking video.

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What size in MB is that 1600*1200 image? Because I can see four mins of motion adding up to alot of size. Now you might be able to use the iPod hard drives, but that's going to drive up the price quickly. But there are other issues, like focusing the lens when it's in place. You also lose all remote viewing. You lose any kind of searching features. You have to check the camera manually for each picture. You have to change out the drives when they fill up....the list goes on.

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Was at the ISC show. It seems like the new thing in CCTV are HD cameras. The picture quality is so much better then the regular CCTV cameras. Kind of expensive right now, but the price will come down like all new technology.

 

In general I don't think the resolotion, camera, dvr, lenses is the main problem, more the installation where people are trying to cover to much ground with the cameras. We always put in a "door camera" at every exit to get a really good close up for identification, and then just use the the rest of the cameras to get the "action". The distance to the subject makes alot bigger difference then the resolution of the camera.

Outside is slightly more difficult though...

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Door cameras can be the most difficult, with the back lighting issues. What type of cams are you using for those doors Fred ?

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We usually put a mini dome right above the door facing inwards instead because of the back light issue. Does the same trick, and no backlight issue.

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gotcha .. yep, was wondering the way around it with the cheaper bullet/dome cameras .. makes sense ..

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In general I don't think the resolotion, camera, dvr, lenses is the main problem, more the installation where people are trying to cover to much ground with the cameras.

 

I agree witht his statement, also many are recording at 640x480 instead of 768x576

 

Door cameras can be the most difficult, with the back lighting issues. What type of cams are you using for those doors Fred ?

 

depends on the quality of the camera actually, and if it has a the abilty to compensate for BLC and if that is central or fullscreen or programmable.

 

We usually put a mini dome right above the door facing inwards instead because of the back light issue. Does the same trick, and no backlight issue.

 

yep always do this, sides, never seen anyone exit a doorway backwards

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Also....

 

you can already get 5 megapixel IP cameras, problem is the bandwidth for the upstream.. lets face it if you want good quality then you need 4 x ciffe resolution and that in MPEG2 is 5200kbps, thats for one camera only so imagine trying to uplaod 16 at once....

 

That is whay what has been invented is a IPwebservers with HDD, this way you can record on motion detection MPEG2 in high quality, but can transmit compressed MPEG4, thsi means you can stream reasonable sized streaming then when an alarm actions then you can stream MPEG2 or retrieve it, they also have ANR technology which sends a live check message to the device so that when a network goes down, the webserver knows when and then resends the missing data to the network recording Device, when the network is back up again.

 

Recording Space and Bandwidth are the two biggest issues at the moment, stopping the movement from going forward, wehn both of these are sorted then we will see high definiton images coming into play.

 

The beaty of the aboe mentioned devices is much more prevelant when you have Hybrid DVR's these are Analogue/IP systems, thsi way you can have say 16 hard wired cams and from the shed down town you can stream one unit to the same box and take it in as a input or convert it back to analogue, seriously if you have 24 shops with only the need for 1 cmarea at each, why put in DVR's when you can network them all...offer voice over I.P. and record for them, they do not need to have a DVR at all, just charge them to store the data and they can web access any events they want to....

 

Think about it...

 

you sell 1 camera and 1 webserver or an i.P. cam, you sell the ISP connection..which would give you prolly 10% commish, then you charge a weekly rate for voice over I.P..at a rate that is only 50% what they pay now and you lock them into monitoring and storage at a monthly rate as well.

 

And you charge them for internet access...so your making four lots of recurring revenue!!!

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Only 4 analogue, i have heard the new Bosch will do 30 Analogue and 30 IP and the excellent lil trick.....you can use the remote software for the DVr to manage the I.P. cams. eliminating your need for things like Milestone, so a free app can be used to control your I.P. cams... rather cheecky really and I doubt it will stay that way!!

 

i saw the Dibos 8 the other day for the first time, nicest GUI I have seen for a long time.. some nice featurs are that it has two analogue outputs and you can drag cameras into them from the mainscreen poping them up on the monitor of your choice.

 

plus a nice scheduled back up feature and the ability to pantilt and zoom within the camera window with the mouse, so moving up, moves the camera up etc... aslo the remote config of the cameras is neat.

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