Remote recording & Management
We are investigating a remote security requirment for a client. He has 5 remote locations where we are proposing two network camera and a video server to interface with existing DVR.

We plan to use a centralized server (currently trialling ONSSI NetDVR) with either DSL or Cable modems at the remotes. To keep the costs down we want to use a residential grade broadband service with 128K uplinks at the remote locations.

We understand that full motion is not preactical at these network speeds, but our client accepts one or two frame per second as realistic. The clarity of the picture is important so we can regonize faces and potetially products they are handling.

Our question is when the NetDVR is set for 1 or 2FPS, we believe this is the rate it records the JPEG images to disk it  recieved across the net. The cameras stream to the network assuming a 10mbps or 100mbps LAN. If more frames are recieved from a particular camera they are thrown away. Is this correct?

We spotted a bandwidth limiter on the camera which we think allows us to limit the output to the local network to 100Kbps. At the broadband router, there is no QOS so three cameras streaming at 100Kbps to the 128K would contend with no guarantee of sequential or periodic frames getting through!

Is it possible for a camera to be configured to capture one image a second, at a specified resolution, say 320x240 with a frame size of 4 kbytes and for this to be sent (FTP??) or retrieved by the NetDVR software so we get best quaility with a consistent 1 second timestamp?


Bob & Mike

Hello Bob & Mike,

All of your assumptions are correct related to FPS.  The question of canyou setup the camera to ftp images to a server is true.  Most IP cameras support two types of image tranfer; FTP and SMTP (E-mail).  They also typically support 4 modes of uploading; Event, Motion, Scheduled, or Continuous.

Event - Physical motion detector or contact closure wired to the back of the camera - most cameras have a I/O block on the back you can wire in security sensors.

Motion - In the last couple of years IP cameras have been adding support on in camera software motion detection so that you can setup images to be uploaded when the camera detects motion via software

Schedule - schedule alarm/continuous uploading based on time

Continuous - sounds like this is what you want - continuous supports the ability to continually upload images based on time seconds, minutes, hours, etc...

I'm not sure if NetDVR supports ftping up images but I know D3Data NETVM support that

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