Milestone XProtect Essential 2014 - Manual (Page 59)

Milestone XProtect ® Essential 2014 Administrator's Manual
www.milestonesys.com 59 Advanced configuration
Advanced configuration
Hardware devices
About hardware devices
You add cameras and other hardware devices, such as video encoders, to your system through the
Add Hardware Devices... wizard (see "Add hardware wizard" on page 43). If microphones or
speakers are attached to a hardware device, they are automatically added as well (if your XProtect
version supports this).
About recording audio
If you record audio, it is important that you note the following:

Your system only records incoming audio (from microphones). The system does not record
outgoing audio (from speakers).

Audio recording affects video storage capacity. The system records audio to the associated
camera’s database. Therefore, it is important to bear in mind that the database is likely to
become full earlier if you record audio and video than if you only record video. The fact that the
database becomes full is not in itself a problem since your system automatically archives data
if the database becomes full. However, you may need additional archiving space if you record
audio.
o Example: If you use MPEG4, each one-second video GOP (Group Of Pictures) are stored
in one record in the database. Each second of audio is stored in one record in the
database. This reduces the database’s video storage capacity to half its capacity, because
half of the database’s records is used for storing audio. Consequently, the database runs
full sooner, and automatic archiving takes place more often than if you were only recording
video.
o Example: If you use MJPEG, audio is stored in one record for every JPEG for as long as
the audio block size does not exceed the time between the JPEGs. In extreme cases, this
reduces the dat
abase’s video storage capacity to half its capacity, because half of the
database’s records is used for storing audio. If you use very high frame rates, which
means less time between each JPEG, a smaller portion of the database is used for storing
audio records, and consequently a larger portion is available for storing video. The result is
that the database runs full sooner, and automatic archiving takes place more often than if
you were only recording video.
The above examples are simplified. The exact available video storage capacity also depends on
GOP/JPEG and audio kilobyte size.
About the Replace Hardware Device wizard
Use the Replace Hardware Device wizard to replace a hardware device that you have previously
added to and configured on your surveillance system. To open the Replace Hardware Device wizard,