7. HARDWARE SETUP
Figure 8: Example for valid stereo camera setup.
focus of both lenses should not be adjusted after the cameras have
been calibrated. An example for a valid camera setup is shown in Figure 8.
The distance between both cameras is referred to as baseline distance. Us-
ing a large baseline distance improves the depth resolution at higher distances.
A small baseline distances, on the other hand, allows for the observation of
close objects. The baseline distance should be adjusted in conjunction with the
lenses' focal length. An tool for computing desirable combinations of baseline
distance and focal length can be found online
7.6 Other Image Sources
SceneScan can also process image data that does not originate from real cam-
eras. To allow for an easy evaluation, each device ships with an example stereo
sequence on its internal memory. This example sequence appears as two virtual
cameras that can be selected during camera conguration (see Section 9.4). If
selected, the example sequence is replayed in an innite loop. Due to speed
limitations of the internal memory, the example sequence is not replayed at
the full frame rate during the rst loop iteration.
Another set of virtual cameras provide the ability to receive image data over
the ethernet port. In this case a computer has to transmit a set of image pairs
to SceneScan, and it then receives the processing results back over the same
network. Please note that this signicantly increases the required network
bandwidth. The bandwidth usage can be reduced by transferring image data
at a lower frame rate. It is highly recommended to always use TCP as
underlying network protocol when performing network transfer of
input imagery, in order to avoid dropped frames (see Section 9.12).
The NVCom client application that is described in Section 11.1 can be
used for transferring a set of locally stored images to SceneScan. This can
be achieved by pressing the appropriate button in the toolbar and selecting a
directory with a collection of image les. The image les in this directory are
then transmitted in alphabetical order. Please make sure that image les for
http://nerian.com/support/resources/calculator/
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