Jump to content
ADFC01

How Do Cameras & FPS Fill Hard Disk?

Recommended Posts

I'm having a lot of trouble getting a clear answer to the relation of cameras and fps to resultant consumption of hard disk space.

 

I'm thinking of buying a cheap (below $150) DVR for security. I'm looking at the DVST-4030, DVQ7 or similar 4-channel models. Since I have 6, 10 and 20GB IDE hard drives sitting around as extra, and these models are sold without storage, naturally I'm thinking of saving money by merging the two. Brand new hard disks are fairly inexpensive, if I need something larger, but I'm still budgeting at most $50 for that.

 

However, I can't make that decision without first knowing how to figure out how 2 cameras at a modest frame rate (8fps) fill up a hard disk. Searching online for such a guide has been fruitless, and DVR sellers merely push 160GB or greater drives on the public.

 

Can you help me figure out a general formula for hard disk capacity when buying and using a DVR? By knowing how the cameras consume disk space, I can decide the frame rate and the days of storage I need.

 

For those who are curious, my application involves neighborhood security. I will place a camera upon each parking spot on the street so that I can keep watch for various thugs breaking car windows. The nighttime lighting may be an issue, but I can adapt to that in time.

Share this post


Link to post
Share on other sites

I`m only another newb, so correct me if I`m wrong, but I would contact your DVR Vendor and ask them. How much disk space you consume per hour/day is going to depend on what resolution-framerate and compression algorithm your hardware-software uses. I figured out the "burn rate" as I call it on the storage of a qlr0444, which is an inexpensive 4 channel PC based system by setting all camera resolution-framerates identical, then setting them to constantly record for 1 hour. I then took the amount of space used to calculate how large a disk I need for however long I wish to retain my images. In my case here, the Qlr0444 burns roughly 2 gig a week if I remember right.. HIGHLY compressed, so the video quality isnt sparkling, but definitely better than an old VCR solution I`ve been able to compare it to.

Hope that helps a lil bit

Share this post


Link to post
Share on other sites

That sounds like my spare drives are more than enough space for a week's worth of 2-camera, 8fps retention. I might be able to increase the frame rate or decrease the compression, for greater use in nabbing thugs. Thanks.

Share this post


Link to post
Share on other sites

$150 DVRs usually have crap compression, so it's either fill the disk fast and have decent video quality (MJPEG) or save the disk and have crap video (MPEG-4 and CIF).

 

You'll need to spend more $ if you want to actually capture something. At least $350-500 anyway. That'll probably get you a 4 port embedded that can do D1 and hopefully MPEG4.

Share this post


Link to post
Share on other sites

To make this simple as possible low end dvrs with 200 gig storage 4 cams with motion turned on store hours 14 hours a day save about 3 weeks of video.

So using 20 gig drives how many hours do you you think you will save?

Also used hard drives will not live long in a dvr running all the time and the heat that builds up in the case due to lack of power supply for proper cooling. So with that being said why try to save money by risking loosing video. You get what you pay for in this market security companies do this for a living and know how to build and install systems that meet your needs.

Are you wanting to view this system over the internet or a network budget dvrs do not offer this option, do you want to view your recorded video while the system keeps recording soory budget dvrs do not offer this option either. The basic starter dvr that offers these are going to be in the $1000.00 and up price range.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×