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Configuration Using NCTerm
NetCam1S, NetCam6, NetCamPlus Manual, © VCS GmbH 51
ing the button ’Level’ the depicted dialog is displayed which allows for configuration
of the audio levels. The volume of the decoded audio signal is to be adapted to the
sensitivity of the connected amplifier or active speaker. Likewise, the used micro-
phone or any other audio source in general determines the setting of the input sensi-
tivity. Settings are stored in non-volatile memory.
Audio transmission can be switched on or off for both transmission directions individ-
ually. In addition, NetCam can be configured to start automatically with audio trans-
mission at connect time. Otherwise audio can be switched on any time later during
the connection. The data rate required for audio is dynamically allocated. As soon as
audio is switched off again, the data rate previously reserved for the audio signal is
again occupied by video transmission, resulting in improved picture quality.
NetCamPlus units with built-in audio allow an external audio source to be used in-
stead of the internal microphone. The input is switched by checking the box under ’Au-
dio Source’, which only appears when a NetCamPlus unit is connected.
When connecting to different remote stations, not all audio coding algorithms might
be available. At connect time the respective units exchange profiles, thereby inform-
ing the other party about their respective capabilities. For example, in combination
with the ViewStation software decoder audio transmission using the algorithm G.728
cannot be selected, as already mentioned above.
6.3.2 Video Control
Video control allows to influence several video coding parameters of the NetCam vid-
eo encoder during an active connection. Basically, there is a choice between two dif-
ferent video resolution modes:
• a high resolution mode, the so-called Common Intermediate Format (CIF) that
provides a spatial resolution of 288 lines by 352 pixels. This is the default resolu-
tion used by NetCam.
• a low resolution mode called Quarter-CIF (QCIF) that provides 144 lines by 176
pixels.
Choosing the low resolution QCIF mode can be adequate, if the available data rate is
severely restricted, as for example for wireless networks. Also, under certain circum-
stances a higher video frame rate might be preferable over a high spatial resolution.
Changing spatial resolution is possible any time during a connection by selecting the
respective button.
The ’Picture-in-Picture’ (PiP)-feature allows to overlay the local video input into the re-
ceived video for a NetCam6 receiver. This is useful if a local video camera should be
continuously monitored, even when the unit is connected to a remote site.