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Hi,

This may sound a little crazy but can some one please answer my quuestions.

I've been wondering about these from a long time.

 

1. Is there any DVR/DVR Card in the world which can record higher resolution than D1. Something around 1280x1024.

 

2. Most security camera have ultra clarity when plugged directly into a TV, but when plugged and recorded in a dvr why does the quality drop so much. Is there anyway to overcome this and record footage just as it would appear on a TV.

 

3. I was considering a GV-2008. To be put into a supermarket . Main activity is in the grocery aisles between 7am to 9pm. I want the very best footage so that its actually worth puting so many cameras and police can easily identify shoplifters. I am looking at 30 fps on each channel at full D1 resolution. I would like the recording to be held for atleast 3 weeks. Would 5 terabytes do the job? I was thinking of getting 5x 1 TB drives and putting them into RAID 5. But i've read somewhere that this may cause problems in terms of a disk failure, it said that if one disk failed than there is a good chance of all others failing in a chain due to read failure when they a trying to rebuild after the first failure. Lastly is Geovision ok with RAID or should I just stick to putting 5x 1tb hdd independently.

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Hi,

This may sound a little crazy but can some one please answer my quuestions.

I've been wondering about these from a long time.

 

1. Is there any DVR/DVR Card in the world which can record higher resolution than D1. Something around 1280x1024.

 

For ANALOG capture, not really. It could be done with an HDTV setup, but those aren't really designed for multi-camera surveillance-type use.

 

For that size, you need to go to megapixel IP cameras, which connect via ethernet and don't require a capture card.

 

2. Most security camera have ultra clarity when plugged directly into a TV, but when plugged and recorded in a dvr why does the quality drop so much. Is there anyway to overcome this and record footage just as it would appear on a TV.

 

Realtime, uncompressed video takes a LOT of space to store. For most purposes, DVR users want to store a lot of footage (most sites I deal with want 30 days' worth). The way to achieve that is by using lower framerates (regular video is 30fps) and high-ratio lossy compression. And with cheaper units, it's partially due to crappy capture cards as well.

 

3. I was considering a GV-2008. To be put into a supermarket . Main activity is in the grocery aisles between 7am to 9pm. I want the very best footage so that its actually worth puting so many cameras and police can easily identify shoplifters. I am looking at 30 fps on each channel at full D1 resolution. I would like the recording to be held for atleast 3 weeks. Would 5 terabytes do the job? I was thinking of getting 5x 1 TB drives and putting them into RAID 5. But i've read somewhere that this may cause problems in terms of a disk failure, it said that if one disk failed than there is a good chance of all others failing in a chain due to read failure when they a trying to rebuild after the first failure. Lastly is Geovision ok with RAID or should I just stick to putting 5x 1tb hdd independently.

 

If you really want the "best" picture, go with megapixel IP cameras. That may require a different DVR, though, as I don't know if GeoVision supports IP yet (a friend's company just lost a big account because they use GeoVision and they couldn't supply the IP-cam support the client wanted... we could, so we got them).

 

You really don't need to run 30fps - even at 15fps, most people would have a hard time telling the difference. 10fps should be more than enough for perfectly usable surveillance video. And if you do go with IP cameras, remember that they take a LOT more storage space than analog - some four times the space at 1280x1024 vs. 640x480, depending on the compression used.

 

I dunno where you've been reading about RAID, but your information is incorrect: the whole point of RAID 5 is to avoid data loss due to disk failure. The catch is, you have to be on top of it if and when a disk in the array does fail.

 

If you use all individual disks, one disk dying will destroy all the data on that drive. If you use RAID 0, striping the data across all drives, one disk dying will destroy ALL your data. With RAID 5, you won't lose and data if one disk dies, but you need to replace that disk to maintain the redundancy. If you don't replace it, and another one dies, THEN you lose everything.

 

http://en.wikipedia.org/wiki/RAID_5#RAID_5 for more details.

 

We just set up a RAID 5 system for a client: 32-input, 480fps VIGIL system, 23 analog cameras mostly running a 640x480 and 3fps, and five 1.3MP IP cameras, initially running at 5fps. The machine itself has 3TB storage and was barely keeping three weeks (closer to 19-20 days).

 

We added an 8-bay Enhance RAID case with eight 1TB drives in a RAID 5 configuration, giving an additional 6.5TB, for a shade under 9.5TB total. That gave them about 82-83 days' worth... they wanted 90 days, so they dropped the IP cams back to 3fps as well.

 

The other trick to saving space is to configure it to only record on motion, rather than recording constantly. In low-traffic areas, and after-hours, that can save a TON of storage.

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Hi,

This may sound a little crazy but can some one please answer my quuestions.

I've been wondering about these from a long time.

 

1. Is there any DVR/DVR Card in the world which can record higher resolution than D1. Something around 1280x1024.

 

2. Most security camera have ultra clarity when plugged directly into a TV, but when plugged and recorded in a dvr why does the quality drop so much. Is there anyway to overcome this and record footage just as it would appear on a TV.

 

3. I was considering a GV-2008. To be put into a supermarket . Main activity is in the grocery aisles between 7am to 9pm. I want the very best footage so that its actually worth puting so many cameras and police can easily identify shoplifters. I am looking at 30 fps on each channel at full D1 resolution. I would like the recording to be held for atleast 3 weeks. Would 5 terabytes do the job? I was thinking of getting 5x 1 TB drives and putting them into RAID 5. But i've read somewhere that this may cause problems in terms of a disk failure, it said that if one disk failed than there is a good chance of all others failing in a chain due to read failure when they a trying to rebuild after the first failure. Lastly is Geovision ok with RAID or should I just stick to putting 5x 1tb hdd independently.

 

1. Yes. It's not cheap and doesn't accept standard cameras. Also the pricing I saw for such systems put it in an extremely high price range. When something makes putting megapixel cameras in look cheap....that's pricey.

 

2. There is always some loss of clarity when doing an analog to digital conversion and when encoding video.

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1. Is there any DVR/DVR Card in the world which can record higher resolution than D1. Something around 1280x1024.

 

1. Yes. It's not cheap and doesn't accept standard cameras. Also the pricing I saw for such systems put it in an extremely high price range. When something makes putting megapixel cameras in look cheap....that's pricey.

 

I've never seen an HDTV surveillance-type capture card... could you provide a link (just for morbid curiosity)?

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1. Is there any DVR/DVR Card in the world which can record higher resolution than D1. Something around 1280x1024.

 

1. Yes. It's not cheap and doesn't accept standard cameras. Also the pricing I saw for such systems put it in an extremely high price range. When something makes putting megapixel cameras in look cheap....that's pricey.

 

I've never seen an HDTV surveillance-type capture card... could you provide a link (just for morbid curiosity)?

 

I don't recall the name. I just remember them having a big booth at ISC West a few years ago.

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I've never seen an HDTV surveillance-type capture card... could you provide a link (just for morbid curiosity)? Smile

 

Hi,

I have learned about Megapixel IP Cameras, definetly HD.

There are IP megapixel cameras which produce higher quality than 1080i.

The best i've seen is the 16Megapixel Avigilon Pro IP Cam. IQ Invision is also good

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I've never seen an HDTV surveillance-type capture card... could you provide a link (just for morbid curiosity)? Smile

 

Hi,

I have learned about Megapixel IP Cameras, definetly HD.

There are IP megapixel cameras which produce higher quality than 1080i.

The best i've seen is the 16Megapixel Avigilon Pro IP Cam. IQ Invision is also good

 

Megapixel CCTV cameras aren't technically "HDTV", despite this overused buzzword being tossed around all the time.

 

I'm just saying...

 

Anyway, the key phrase above is "capture card" - ie. hardware that takes analog HD video input and digitizes it. Yes, they exist for "consumer" markets, but I've never seen one designed for CCTV use (particularly not multi-camera).

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The best DVR today is average!

 

I think that the DVR board companies should work on ways to enhance quality of the image, as well as the CCD manufactures, what about tweaking a HikVision compression card like DS-4008HF that today is giving you 8 channels, 4CIF recording resolution at 30(25)FPS into a high resolution/high bitrate card for 4 channels?

 

I am not happy with the quality!

 

 

JD

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You can't really get much more than 4CIF out of standard NTSC video, is the point, so capture resolutions higher than around 720x480 are next to meaningless until you move into the HD (720i/p/1080i/p) realm. At that point, the cameras get much more expensive, the analog capture devices get much more expensive (and hard to find), the wiring requirements get much MUCH more expensive, and you're far better off just going to megapixel IP cameras.

 

If you DID go above 4CIF on standard analog capture, it would also get much more expensive, because you no longer have the economy of scale: cards these days benefit from a glut of mass-produced digitizers, like the Bt848, so they're cheap to build and easy to support (generic drivers, etc.). Building cards that capture above that would require different, more expensive, non-mass-availability components and probably more hardware, driver, AND software development cost... and only up to the maximum capabilities of the cameras (max 520TVL for most NTSC cameras). For the relatively minimal improvement you'd see, it really wouldn't be worth the additional cost to the end user, especially not with megapixel IP cameras getting so cheap.

 

And BTW, HikVision is far from "the best" available right now...

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If you want to get the most of your analog cameras, you should look at Avigilon's networked video encoder. It's much cheaper than the typical DVR card (a few hundred dollars), and it let me record 4 D1 channels (up to 768x576) at 30 fps with no drop in picture quality. In fact it looks much sharper on the computer than it did directly on my TV. I think they do adaptive contrast enhancement.

 

Basically, it turns 4 analog cameras into individually accessible IP cameras with smart motion-triggered recording. Since those 4 channels count as 1 IP camera, it only takes a single camera license on the Avigilon software, so it's definitely the most cost-effective solution I've found so far.

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if you are worried about raid5, go raid6, then 2 drives need to fail for you to lose the array. fwiw, raid5 is extremely safe, imho raid6 is a bit paranoid, but if you have the raid card that can do it, it is just another hdd.

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if you are worried about raid5, go raid6, then 2 drives need to fail for you to lose the array. fwiw, raid5 is extremely safe, imho raid6 is a bit paranoid, but if you have the raid card that can do it, it is just another hdd.

 

Agreed, especially since space is so cheap these days ($200 for 1TB). The only catch is where you run into other limitations in space - on the last one of these I did, 8 1TB drives in an 8-bay rack, RAID 6 would have been nice, but the 6.5TB we got from RAID 5 (with system and parity overhead) was bare minimum for the retention we were trying to achieve; RAID 6 would have cost another 1TB of that, and the next step up would have been to a 16-bay rack at substantially higher cost.

 

Most good enclosures/cards, though, will give you a pretty hard-to-ignore warning if a drive fails, so you can swap it out before anything further happens...

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amazing to see the 1.5TB drives coming online for less than $200 too. man, that is a lot of space

 

 

1 Petabyte drive will be ridiculous

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