Vivotek VS2403 Network Card User Manual


 
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A The plug-in provided by Video Server is used to display motion pictures on Internet
Explorer that does not support server push technology. If your system does not allow
installation of any plug-in software, the security level of web browser may need to be
lowered. It is recommended that you consult your network supervisor in your office
regarding the adjustment of the security level.
Q Why is the timestamp different from the system time of my PC or notebook?
A The timestamp is based on the system time of Video Server. It is maintained by a
real-time clock inside and automatically synchronizes with the time server if Video
Server is connected to the Internet and the function is enabled. Differences of several
hours may result from the time zone setting.
Q How many users are allowed to watch Video Server at the same time?
A To achieve the best effect, Video Server will allow twenty users to connect at the same
time. Excess users can get an auto-refreshed still image in homepage instead. It is
recommended to build another web server to host a large quantity of users by retrieving
images from Video Server periodically.
Q How fast is the video rate of Video Server?
A The JPEG codec can process 30 frames per second internally. However the total
performance is subject to many coefficients as follows,
1. network throughput,
2. bandwidth share,
3. number of users,
4. number of video inputs are accessed at one time,
5. the complicated objects in view results in larger image file,
6. the level of your PC or notebook which is responsible of displaying images.
In general, the transfer rate in general local network environment can achieve over 200
kilobytes per second and approximately 10 to 20 pictures of normal environment per
second. The general frame size is illustrated in the follow table for reference.
Quality setting Size of each frame Bandwidth demand for 30fps
Medium 6.51 kbyte 1562 kbps
Standard 6.69 kbyte 1606 kbps
Good 9.29 kbyte 2230 kbps
Detailed 14.28 kbyte 3427 kbps
Excellent 24.24 kbyte 5818 kbps
Q How can I keep Video Server as private as possible?