SVS-Vistek CameraLink svs16000, Руководство пользователя

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Users Manual Area Scan Cameras SVSGigE Page 68
Users Manual –svs11002 and svs16000
© SVS-VISTEK GmbH
take multiple images until a final balance is reached. Once a balance is adjusted, the
tap balance is finished and the gain factors are not changed anymore. Those gain
factors will apply until the camera is closed.
An application can take more control over the auto tap balance process if this is
needed. The following options are offered for “auto tap balance” mode:
 Off
 Once
 Continuous
An application can switch auto tap balance OFF before opening a streaming channel in
order to prevent from running any adjustments. Further an application can switch
auto tap balance to ONCE at any time in order to run a one-time adjustment of tap
balance. Only in case of big changes of gain and exposure during a camera usage it
might be recommended to switch auto tap balance to CONTINUOUS. In that case
every captured image is checked for tap balance and individual gain factors for right
and left balance are adjusted appropriately whenever this is needed. There is no
visible runtime penalty when switching auto tap balance to CONTINUOUS since only a
small stripe left and right the middle of the sensor are taken into account for
evaluating a deviation from tap balance.
The following two functions allow for switching the auto tap balance mode to
explained values and for retrieving current state:
Camera_setAutoTapBalanceMode(Camera, AutoTapBalanceMode);
Camera_getAutoTapBalanceMode(Camera, *AutoTapBalanceMode);
A reset to factory defaults or to arbitrary values inside a range of +/- 1.5 dB can be
performed by the following function. The second function retrieves current setting:
Camera_setTapBalance (Camera, TapBalance);
Camera_getTapBalance (Camera, *TapBalance);
16.11.10Distributing image streams by multicast
The image stream of a GigE camera can be distributed to multiple PCs by using the
multicast capabilities of current network hardware, in particular multicast-enabled
switches. The following picture explains the basic principle:
A camera streams image data in a certain IP range (232.x.x.x) which has been
determined for dynamic local host multicast allocation by the IANA organisation (see
http://www.iana.org/assignments/multicast-addresses for more details).
A multicast-enabled switch is supposed to distribute the image stream to one, two or
more applications. The advantage of having a switch distributing image streams is the
optimal bandwidth usage between camera and switch as well as between switch and
particular applications. There is no bandwidth wasted in the described scenario.
A multicast session consists of one controlling application and one or more listening
applications. Only the controlling application has write-access to the camera. All other
applications can only listen to the image stream that is initiated and controlled by the
controlling application.