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Ways of Recording
MOBOTIX cameras offer a selection of three
different recording modes:
-
Event clip with
variable frame rate and
audio,
-
Continuous recording
with event-controlled frame
rate increase including
audio,
-
Single frame without
audio with pre and
post-alarm images.
Recording always takes place in
the
ring buffer process; that
means that the camera deletes
old images if storage space
becomes tight or if the set
retention time elapses. Images
are stored either in the camera
or on a PC/server. There is no
need to install any plugins
because the MOBOTIX cameras
manage the image and audio data
themselves.

The
recording processes are
independent of the selected
encoding type (JPEG, MxPEG).
However, the highest frame rate
and the most effective storage
can be achieved with the
MOBOTIX-specific MxPEG process.
In parallel to event-controlled
recording, history images
can be saved cyclically in the
ring buffer. Where necessary,
your image format may differ
from the live image. This means,
for example, that an additional
megapixel image can be saved
every 10 minutes for
event-controlled video/audio
recording in VGA format.
Event Clip with Audio
A
video and audio clip of
variable length are recorded
in the event clip process. The
frame rate can be up to 25 fps.
This mode is used as standard in
security technology. It only
starts recording in response to
actual events, such as motion,
in the camera image. With an
advance run of up to 10 seconds,
the run-up to an event can also
be recorded. Irrespective of the
live frame rate set, the storage
frame rate can be adapted in
line with requirements and the
available storage capacity.

The
event clips are divided into 10
second parts (files) and stored
on the PC in a folder in the
ring buffer. This greatly
reduces the number of files
compared to a comparable single
frame process with pre and
post-alarm images. The recording
PC is about 10 times more
efficient that the old process.
Since the camera's internal
temporary buffer also reduces
the peak network load,
altogether 100 cameras can
save their images on a single PC
on an event-controlled basis.

Continuous Recording with an
Event-Controlled Frame Rate
In the case of continuous
recording, images are recorded
on a continuous basis during the
set time of the week, for
example from 8 am to 6 pm Monday
through Friday. The storage
frame rate can be set at between
0.2 and 25 Hz, differing from
the live frame rate. In
addition, the frame rate can be
raised automatically if an event
occurs. For example, continuous
recording can be selected with
an image sequence of five
seconds (0.2 Hz) to then be
increased to 25 fps if an event
is detected.

The
video stream is saved in the
ring buffer in clear parts of 10
seconds in length. Thanks to
this efficient process, around
30 cameras can record a live
video stream on a standard PC
(Pentium 4, 3.2 GHz)
simultaneously at a rate of 25
fps including audio.
If images need to be recorded
from a larger number of cameras,
other devices or servers can
simply be added at any time. The
number of cameras per server can
be increased in conjunction with
a high-spec server PC and a RAID
(remote access identification
device) disk system. The MOBOTIX
process is more efficient than
and superior to classical
recording with central PC
software, in particular in
recording at high frame rates.

Single Frame with a Pre- and
Post-Alarm
In a single frame process,
images of the event are saved in
separate JPEG files. In
addition, up to 50 pre and
post-alarm images can be saved
at fixed time intervals in
individual files. These images
(files) are then combined in one
folder in the ring buffer which
is named after the number of the
event.
The advantages of the single
frame process are the low
storage capacity for the single
image, as well as the
possibility of lengthy intervals
of up to 10 minutes between pre
and post-alarm images. Since the
images are saved as separate
JPEG files, they can be accessed
not only with the integrated
playback functions via the
browser, they can also be
accessed directly by hand or by
other programs via the folder.
However, the disadvantage of the
single frame process is that if
there are a large number of pre
and post-alarm images and very
frequent events from several
cameras, the server is subject
to a greater load than in the
other two processes.

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