National Instruments IMAQTM 사용자 설명서

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Chapter 2
Getting Measurement-Ready Images
© National Instruments Corporation
2-3
Complex
32-bit RGB
32-bit HSL
64-bit RGB
When you create an image, it is an 8-bit image by default. You can set the 
Type
 property on the image object to change the image type.
When you create an image, no memory is allocated to store the image 
pixels. IMAQ Vision methods automatically allocate the appropriate 
amount of memory when the image size is modified. For example, methods 
that acquire or resample an image alter the image size, so they allocate the 
appropriate memory space for the image pixels.
Most methods belonging to the IMAQ Vision library require an input of one 
or more image objects. The number of images a method takes depends on 
the image processing function and the type of image you want to use.
IMAQ Vision methods that analyze the image but do not modify the image 
contents require the input of one source image. Methods that process the 
contents of the image require one or more source images and a destination 
image. Exceptions to the preceding statements are methods that take a mask 
image as input.
The presence of a 
MaskImage
 parameter indicates that the processing or 
analysis is dependent on the contents of the mask image. The only pixels 
in the source image that are processed are those whose corresponding 
pixels in the mask image are non-zero. If a mask image pixel is 0, the 
corresponding source image pixel is not processed or analyzed. The mask 
image must be an 8-bit image.
If you want to apply a processing or analysis method to the entire image, 
do not supply the optional mask image. Using the same image for both the 
source image and mask image also has the same effect as not using the 
mask image, except in this case the source image must be an 8-bit image.
Most operations between two images require that the images have the same 
type and size. However, arithmetic operations work between two different 
types of images. For example, an arithmetic operation between an 8-bit 
image and 16-bit image results in a 16-bit image.