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Chapter 2
Getting Measurement-Ready Images
© National Instruments Corporation
2-5
imaqAdd(myImageA,
 
myImageA,
 
myImageB);
This function adds two source images and stores the result in the first 
source image.
imaqAdd(myImageB,
 
myImageA,
 
myImageB);
This function adds two source images and stores the result in the 
second source image.
Most operations between two images require that the images have the 
same type and size. However, some arithmetic operations can work 
between two different types of images, such as 8-bit and 16-bit images.
Some functions perform operations that populate an image. Examples of 
this type of operation include reading a file, acquiring an image from an 
IMAQ device, or transforming a 2D array into an image. This type of 
function can modify the size of an image.
Some functions take an additional mask parameter. The presence of this 
parameter indicates that the processing or analysis is dependent on the 
contents of another image, the image mask.
Note
The image mask must be an 8-bit image.
If you want to apply a processing or analysis function to the entire image, 
pass NULL for the image mask. Passing the same image to both the source 
image and image mask also gives the same effect as passing NULL for the 
image mask, except in this case the source image must be an 8-bit image.
Acquire or Read an Image
After you create an image reference, you can acquire an image into your 
imaging system in three ways. You can acquire an image with a camera 
through your IMAQ device, load an image from a file stored on your 
computer, or convert data stored in a 2D array to an image. Functions that 
acquire images, load images from file, or convert data from a 2D array to 
an image automatically allocate the memory space required to 
accommodate the image data.