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security DVR is one of the best ways society to protect safety now, it can not only protect family safety,but also can protect the enterprise, the property and other facilities of security, since these advantages, security dvr is now more and more people and the company pays attention to as protection of their tools.
A security DVR systemis the core component for any surveillance system. It records, compresses, stores, manipulates, basically manages all recorded data. Unlike onld VCR systems, DVRs offer the flexibility of keeping surveillance of your property regardless of where your are in the world. As long as you have internet access you can view your property via. computer or smart phone.
How many DVR channels?
security DVRswill offer you multi or various channel options. Each channel allows you to connect
a security camera for recording.
security DVR's for home or small business typically offer 4, 8,
9, 16, 32 channels or more.
So, for example if your particular security application is limited to needing only 4 maybe 5
surveillance cameras than you’ll want to error on the high side and get an 8 channel DVR security system(image) so you won’t get stuck needing to buy another dvr to upgrade. Besides you may move
from your current home or business to a new location that requires more camera coverage.
How Many FPS?
Frames per second or FPS relates to how many frames per second your DVR will record. You’ll often
see numbers betwee 7.5 FPS to as high as 480 FPS or more. Realize the FPS needs to be divided by
the number of channels on your DVR. If you’re looking at a 4 channel DVR with a frame rate of
120 and you connect 2 cameras, then each camera will record at 60 FPS each.
That’s great!
Add 2 more cameras for a total of 4 and your FPS drops to 30 per camera. Still good.
As a benchmark video cameras typically record at around 30 FPS. So if you get a 4 channel DVR that
rated at only 30 that translates to 7.5FPS per camera. The footage won’t be smooth and you run the
risk of missing something important should you need to use it later in court. Its best to keep
your security DVR fps around 30 (for each cam) to get clear, full motion viewing.
How Much Storage Capacity?
Most DVR’s are equipped with internal storage or hard drives. Video eats up a lot of storage
fast. The amount of storage space your security DVR needs is proportional to several factors:
* Size of security DVR hard drive (250 GB to 8 TB)
* How many frames per second (FPS) your DVR records
* How many security cameras you use (4 to 64)
* How often your cams record (all day or only when motion is detected)
Don’t worry, here’s how to configure how long your storage capacity will last before it
overwrites the oldest footage. Security DVR video storage Calculator. How much storage is again
relative to your specific needs. If you’re a bank you’ll most likely need at least 60 days of
footage stored. If you’re home surveillance system only needs 4 or 5 days of video footage than
you can save by downsizing any one or all of the above factors.
Which Compression Format?
You can minimize the amount of storage space your security DVR needs by evaluating the type of
video compression or encoding you select. Most security DVR systems give you the following
compression format options:
* MJPEG (old)
* MPEG-4 (much better but reliant on software for encoding video)
* H.264 (best as it relies on hardware for encoding while offering better image clarity)