Area Of Interest (Aoi) - Basler L800k User Manual

Operation and Features

3.7 Area of Interest (AOI)

The area of interest feature is not available when the dual separated video data out-
put mode (see Section 2.5.5.3) is selected.
The area of interest feature lets you specify a portion of the CCD array and during operation, only
the pixel information from the specified portion of the array is signaled as valid to the frame
grabber. Pixels outside of the AOI are transmitted to the frame grabber as black pixels and are
signaled to the grabber as invalid.
The size of the area of interest is defined by declaring a starting pixel and a length in pixels (see
Figure 3-10). For example, if you specify the starting pixel as 10 and the length in pixels as 15, the
camera will output all of the pixel values for the array but only pixels 10 through 24 will be signalled
as valid.
Figure 3-10: Area of Interest
When the area of interest feature is used, the number of transmitted pixels does not decrease and
the maximum achieveable line rate does not increase.
Valid pixels are signalled using the line valid and data valid bits. On the pixel clock cycle where
AOI data transmission begins, the line valid and data valid bits will become high. After the pixel
clock cycle where AOI data transmission ends, the line valid and data valid bits will become low.
For example, if you specify the starting pixel as 7 and the length as 8148, the line valid and data
valid bits will become high on the clock cycle where pixel 7 is transmitted (see Figure 3-11). After
the 8148 pixels in the AOI have been transmitted, the line valid and data valid bits will become low
indicating that valid line data is no longer being transmitted.
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Draft
BASLER L800
k