User guide

Digital Video Hardware User Guide
revision 38 — 23
NTSC or 12.5 fps PAL), 1 reference frame every two seconds when recording at
any other frame rate.
The quality of recorded video is determined by the combination of the configured
compression level, configured frame rate and amount of motion.
Video compression is software configurable through the System Administration
Application. The compression level ranges from 0 to 100%. The suggested
compression value is 75% for the DV-4UP-30F, and 50% for the DV-8UP-S.
Note: There are limited improvements in video quality when using compression
values less than the suggested values, especially when you consider the disk
space required to achieve these lower values.
Frame Rates
The LDVR-SP can operate at a frame rate of up to 15 frames per second per
camera per video capture board when only two cameras are connected to that
board (based on a system with 1-2 cameras running, NTSC). This means that it
can operate at a frame rate of up to 30 fps NTSC (25 fps PAL) per an 8-channel
digital video board. Note that as the number of cameras increases, the frame rate
decreases because the total frame rate for each board is distributed among all the
cameras connected to it.
Frame rates are software-configurable. If there is no setting specified, by default
the frame rate for NTSC cameras is 3.7 fps and the rate for PAL cameras is 3.1
fps. You may choose one of five different frame rate settings.
Frame rates available for NTSC video standard: 15.0, 7.5, 3.7, 1.8, and 0.9.
Frame rates available for PAL video standard: 12.5, 6.2, 3.1, 1.5, and 0.7.
Number of
cameras
MTSC maximum (per
camera per 8-channel
digital video board)
PAL Maximum (per camera
per 8-channel digital video
board)
1 15 frames per second 12.5 frames per second
2 15 frames per second 12.5 frames per second
3 7.5 frames per second 6.25 frames per second
4 7.5 frames per second 6.25 frames per second
5 or more 3.75 frames per second ~3.125 frames per second