Image Acquisitionand Proces

3
Image Acquisition
There are two main methods of obtaining images: loading from disk and acquiring
directly using a camera. Image acquisition is often considered a complex task, but
it can be simpliÞed for most vision applications. National Instrument’s Measurement
and Automation Explorer (MAX), LabVIEW and the Vision Toolkit make image
acquisition a straightforward and integrated task.
3.1 CONFIGURING YOUR CAMERA
The range of cameras available to use with your vision system is astounding – several
different types exist across brand lines (more information of camera types can be
found in Chapter 2). If you are using a National Instruments image acquisition card,
MAX depends on a camera deÞnition Þle to understand the conÞguration of the
camera attached to the card. ConÞguration Þles for common cameras are included
with a standard NI-IMAQ installation (Figure 3.1)
An icd Þle contains all of the information MAX and subsequently IMAQ needs to
acquire images and control the camera. Figure 3.2 illustrates an example icd Þle. As
shown, the icd Þle is of a human-understandable format, and can be manually edited
using Notepad, or a similar ASCII text editor. As the camera conÞguration Þle extension
is icd, the Windows ® operating system should not have an application registered to
launch the Þle type by default; therefore, you will need to manually open the Þle for
FIGURE 3.1 icd Þle directory.
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