Rockwell Automation 5370-CVIM2 Module - Manual (Page 75)

Chapter 3
Image Acquisition Parameters
3–36
however, the Acq.Phase (Pixels) value can be set within the following
range:
*(640 –
Acq. Pixels )
B
2
x
Value
x )(640 –
Acq. Pixels )
B
2
NOTE: Changing the Acq. Pixels and Acq. Phase values does not affect
the image acquisition time.
The example in Figure 3.26 shows the effect of changing the value of the
Acq. Phase (Pixels) parameter to 64 (with the Acq. Pixels (Pixels)
parameter set to 512, in this case). Note that this image appears shifted to the
left, compared to the “512” image shown in Figure 3.25 (page 3–35). In fact,
the leftmost 64 pixels of the image are truncated in this case.
Figure 3.26 Example: Effect of Maximum Acq. Phase Setting on Displayed Image
Acq. Pixels = 512 Acq. Phase = 64
In Figure 3.27 (A) on page 3–37, the dotted lines show that the center of the
512 acquired pixels is centered in the full 640–pixel image when
Acq.
Phase (Pixels) is set is 0. In Figure 3.27 (B), the dotted lines show that the
center of the 512 acquired pixels has moved 64 pixels to the right when the
Acq. Phase (Pixels) is set is 64 (this is the example shown in Figure 3.26).
Note that the reverse would be true if the Acq. Phase (Pixels) were set to
–64. In that case, the displayed image would appear shifted to the right.
In another example, shown in Figure 3.27 (C), if you wanted only the
rightmost 200 pixels in the image to be acquired, you could set
Acq. Phase
(Pixels) to 220 and Acq. Pixels (Pixels) to 200.