G) Serial Ports - Sentry LE Series Manual

LE/LE-HC Series DVR User Manual
V1.4
Set Video Compression Algorithm & Resolution
Select one of four Compression algorithms. These are MPEG4, H.263, JPEG or Motion-JPEG.
Please refer to the table below for relationship between Compression format, Video quality & Data
rate:
Compression Format
*Please Note: The only compression format available on the LE-HC is MPEG4.
The best compression format depends on network connections; both locally and remote.
Remember that a 3 MB DSL connection means 3 MB download, not 3 MB upload. The 3 MB DSL
can be as low as 284K upload or even 128K. This will have an affect on the remote video frame
rate. Observing video produced remotely under different compression algorithms is the best way
to evaluate requirements. The LE Series DVR is set to H.263 compression as a default. This
provides the fastest video transmission speeds, the smallest recorded files and satisfactory video
quality.
When setting video resolution, remember that 640X480 resolution needs 4 times the physical
bandwidth than that required to produce the same frame at 320X240. Once again, look at the
video and see if the speed loss of frames is worth the increase in resolution quality.
"Set IP Registry Host IP Address & Path" is used where static IPs are unavailable or
impractical. Basically, the LE/LE-HC Series DVR sends its current IP to a computer designated as
a registry (usually a commercial service). Remote users can then access that registry and find out
what the current IP is. This is an imprecise service at best, and is prone to failure, due to the
nature of the internet. However, in cases where a static IP is not available, it is still invaluable.
g) Set Serial Ports
Settings for COM1 and COM2 need only be applied in cases where a GPIO, Modem or PTZ,Voice
Call, Data Capture, Control device is connected to the DVR.
Settings for these particular devices will vary by brand. Specific questions regarding this topic
should be directed to the vendor. Please be aware that not all brands (especially PTZ cameras)
are compatible with this DVR.
Video Quality
JPEG Very Good
M-JPEG
H.263
MPEG4
Good High (Less than JPEG)
Average
Good
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October 2006
Data Rate
High
Low
Low