50
•
Bit Rate:
You can select different bit rates to accommodate different settings of
resolution and frame-rate options include: (bps): 32K, 48K, 64K, 80K, 96K, 128K,
160K, 192K, 224K, 256K, 320K, 384K, 448K, 512K, 640K, 768K, 896K, 1M,
1.25M, 1.5M, 1.75M, 2M and “User define”.
The appropriate max bit rate selection is related to the resolution selected. If you
select a high resolution, you must select high bit rate. For CIF resolution, the
typical max bit rate is 384K~768Kbps for real time compression. For 2CIF/DCIF
resolution, the typical bit rate is 512K~1Mbps real time compression. For 4CIF
resolution, the typical bit rate is 1.25Mbps~1.75Mbps for real time compression.
Of course, you will select the proper bit rate based on the camera, background
and image quality requirement.
•
Frame Rate:
Frames per second. Options are: Full (NTSC is 30 FPS and PAL is
25FPS), 20, 16, 12, 10, 8, 6, 4, 2, 1, 1/2, 1/4, 1/8, 1/16. For lower frame rates you
can select low bit rates to save bandwidth.
Note:
Some series DVRs may have lower frame rates for a particular resolution.
•
PreRecord Time:
This sets the buffer size for retaining video/audio when you
enable motion detection recording or external alarm recording. You can define a
prerecord time. The options are: No Prerecord, 5 Seconds (default selection), 10
Seconds, 15 Seconds, 20 Seconds, 25 Seconds, 30 Seconds and Max Prerecord.
MaxPreRecord saves all data in Prerecord buffer. The Prerecord time is
related to the bit rate (the lower the bit rate, the longer the Prerecord time).
• If the bit rate (Max bit rate) is very low, and you select the “Prerecord Time” as “5
Seconds” the actual prerecord time is more than 5 seconds. On the other side, if
the bit rate is high, and the “Prerecord Time” is set to “30 Seconds,” the actual
prerecord time may be less than 30 Seconds.
•
PostRecord Time:
This sets the length of time the DVR will continue to record in
alarm record mode after the alarm clears. When external alarm or motion alarm
ends, the DVR will continue recording for a selected period of time. The options
are: 5 Seconds (default), 10 Seconds, 30 Seconds, 1 Minute, 2 Minutes, 5
Minutes and 10 Minutes.
•
Enable Rec:
This setting determines whether the camera will record. Recording
may be halted based on additional schedule settings.
•
Schedule:
When you enable recording function, you can setup recording
schedule.
Note:
When the camera’s recording schedule is modified, you must reboot the DVR
before the changes will take effect.
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