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If the image quality meets your needs, use the histogram to determine the 
range of pixel values that correspond to objects in the image. You can use 
this range in processing functions, such as determining a threshold range 
during particle analysis.

If the image quality does not meet your needs, try to improve the imaging 
conditions to get the necessary image quality. You may need to re-evaluate 
and modify each component of your imaging setup, including lighting 
equipment and setup, lens tuning, camera operation mode, and acquisition 
device parameters. If you reach the best possible conditions with your setup 
but the image quality still does not meet your needs, try to improve the 
image quality using the image processing techniques described in the 
Improve an Image section of this chapter.

Use 

imaqLineProfile()

 to get the pixel distribution along a line in the 

image, or use 

imaqROIProfile()

 to get the pixel distribution along a 

one-dimensional path in the image. By looking at the pixel distribution, you 
can determine if the image quality is high enough to provide you with sharp 
edges at object boundaries. Also, you can determine if the image is noisy 
and identify the characteristics of the noise.

If the image quality meets your needs, use the pixel distribution 
information to determine some parameters of the inspection functions you 
want to use. For example, use the information from the line profile to 
determine the strength of the edge at the boundary of an object. You can 
input this information into 

imaqEdgeTool2()

 to find the edges of objects 

along the line.

Using the information you gathered from analyzing your image, you may 
want to improve the quality of your image for inspection. You can improve 
your image with lookup tables, filters, grayscale morphology, and FFTs.