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Chapter 2
Basic Acquisition with NI-IMAQdx
© National Instruments Corporation
2-9
Decoding images requires CPU resources. However, many of the decoding 
algorithms have been optimized in the driver. If you do not want decoded 
image data, you can use NI-IMAQdx to get a copy of the raw camera 
output.
Programming Examples
This section contains examples of high-level and low-level image 
acquisitions. Refer to th
 section of Chapter 1, 
, for directory paths to the code examples 
discussed in this section.
High-Level Function Examples
Use high-level functions to write programs quickly without having to learn 
the details of the low-level API and driver.
Snap
A snap acquires a single image into a user buffer. Figure 2-2 illustrates the 
typical programming order of a high-level snap acquisition.
Figure 2-2.  High-Level Snap Flowchart
Use a snap for low-speed or one-shot applications where ease of 
programming is essential. When you invoke a snap, the driver opens
a session on a camera and initializes the camera. Opening a session
sets the ROI to the size of the settings you configured in MAX.
Open
Opens and configures camera
Executes user-specific image
processing
Closes the camera session
Acquires image into buffer 
Snap
User-Specific Functions
Close