National Instruments IMAQTM 用户手册

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Chapter 2
Getting Measurement-Ready Images
2-2
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color and monochrome devices as well as digital devices. Visit 
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 for more information about IMAQ devices.
4.
Configure the driver software for the image acquisition device. If 
you have a National Instruments image acquisition device, configure 
the NI-IMAQ driver software through Measurement & Automation 
Explorer (MAX). Open MAX by double-clicking the Measurement & 
Automation Explorer icon on the desktop. For more information, refer 
to the NI-IMAQ User Manual and the Measurement & Automation 
Explorer Help for IMAQ
.
Calibrate Your Imaging System
After you set up the imaging system, you may want to calibrate the system. 
Calibrate the imaging system to assign real-world coordinates to pixel 
coordinates and compensate for perspective and nonlinear errors inherent 
in the imaging system.
Perspective errors occur when the camera axis is not perpendicular to the 
object under inspection. Nonlinear distortion may occur from aberrations 
in the camera lens. Perspective errors and lens aberrations cause images to 
appear distorted. This distortion displaces information in an image, but it 
does not necessarily destroy the information in the image. 
Use simple calibration if you want only to assign real-world coordinates to 
pixel coordinates. Use perspective and nonlinear distortion calibration if 
you need to compensate for perspective errors and nonlinear lens distortion. 
For detailed information about calibration, refer to Chapter 6, 
Create an Image
The CWIMAQImage object encapsulates all the information required to 
represent an image. 
Note
CWIMAQImage is referred to as an 
image
 in the remainder of this document.
An image can be one of many types, depending on the data it stores. 
The following image types are valid:
8-bit
16-bit
Single-precision floating point