National Instruments IMAQTM 用户手册

Use 

CWIMAQVision.FillHole

 to fill holes in the particles. Use 

CWIMAQVision.Morphology

 to perform a variety of operations on the 

particles. You can use the Open, Close, Proper Open, Proper Close, and 
auto-median operations to smooth the boundaries of the particles. Open and 
Proper Open Smooth the boundaries of the particle by removing small 
isthmuses, while close widens the isthmuses. Close and Proper Close fill 
small holes in the particle. Auto-median removes isthmuses and fills holes. 
For more information about these operations, refer to Chapter 9, Binary 
Morphology, in the IMAQ Vision Concepts Manual.

After you create a binary image and improve it, you can make particle 
measurements. With these measurements you can determine the location of 
particles and their shape features. Use the following methods to perform 
particle measurements:

•

CWIMAQVision.ParticleReport

—This method returns a 

CWIMAQParticleReport object, which contains, for each particle, 
nine of the most commonly used measurements, including the particle 
area, bounding rectangle, and center of mass. The bounding rectangle 
is returned as one measurement, but contains four measurement 
elements. The center of mass is returned as one measurement, but 
contains two elements.

•

CWIMAQVision.ParticleMeasurement

—This method takes the 

measurement you want to apply to all particles, and returns an array 
that contains the specified measurement for each particle.

Table 4-1 lists all of the measurements that 

CWIMAQVision.ParticleMeasurement

 returns.

Table 4-1.  Measurement Types

cwimaqMeasurementArea

Area of the particle. 

cwimaqMeasurementAreaByImageArea

Percentage of the particle Area covering 
the Image Area. 

cwimaqMeasurementAreaByParticleAndHolesArea

Percentage of the particle Area in 
relation to its Particle & Holes’ Area.