Camera Performance and Features
43
Note: The Binning parameters can only be changed when image transfer to the frame grabber is
stopped. Refer to the “Acquisition and Transfer Control’ category in the appendix for details on
stopping and starting the acquisition.
Using Area of Interest to Reduce Image Data & Enhance Performance
See the section Image Format Control Category in Appendix A for GenICam features associated
with this section and how to use them
Related Features: AOI Count, AOI Selector
,
AOI Offset, AOI Width
If the camera’s field of view includes areas that are not needed for inspection (also refer to the
description in the Flat Field Calibration Region of Interest section) then the user may want to
ignore this superfluous image data.
Eliminating unwanted image data that is visible in the camera’s field of view reduces the amount of
information the host computer needs to process. This may result in an increase to the maximum
allowable line rate when using 12-bit output data.
The camera can accommodate up to four AOIs. Image data outside the AOIs is discarded. Each AOI
is user selected and its pixel boundaries defined. The camera assembles the individual AOI’s into
one contiguous image line with a width equal to the sum of the individual AOIs. The frame grabber
will need to be adjusted to accommodate the smaller overall image width. As the host computer
defined the size of each individual AOI’s, it will be able to extract and process each individual AOI
from the single larger image.
Steps to Setup Area of Interest
1.
Plan your AOIs.
2.
Stop acquisition.
3.
Set the number of AOIs.
4.
Select the first AOI and set the offset and width.
5.
If the other AOIs are large then you may need to select them first and reduce their widths.
6.
Repeat for each AOI in turn.
7.
Start acquisition.
The Rules for Setting Areas of Interest
The rules are dictated by how image data is organized for transmission over the available
CLHS data lanes.
The camera / XML will enforce these rules, truncating entered values where necessary.
1.
Acquisition must be stopped to change the AOI configuration.
2.
1-4 AOI's can be selected.
3.
Minimum width is 96 pixels per AOI.
a.
Minimum total of all AOI widths summed together must be at least 1,024.
4.
Maximum width of all AOI widths summed together must be no more than = 16,384.
a.
There can be maximum 8k bytes per CLHS lane.
5.
AOI width step size is 32 pixels.
6.
The offset of each AOI may be 0 to (16,384 – 96 = 16,288).
a.
Therefore overlapping AOI's are allowed.
7.
Offset and width for individual AOI's will "push" one another.
a.
E.g. if AOI has offset 0, width 16,384, and the offset is changed to 4096, then the
width will be "pushed" to 12,288.