Setting a minimum for histogram calculation using Histogram2 function in IMAQ

[Steverino]

I am using IMAQ for Measurement Studio (VB). In the old "Histogram" function, one could set a min or max for calculating the gray scale histogram. Can something similar be done using the "Histogram2" function?

Thanks!

[Scott_R]

Hello,

The Histogram2 function does, in fact, have that functionality as well. One of the inputs, CWIMAQHistogramOptions, has a property called PixelRange. This property has Min and Max parameters that can be set. By doing this, you can specify the range or pixel values that you want to analyze with the Histogram2 function.

To see the explanation for each of those parameters and the PixelRange property, take a look at the IMAQ Vision for Visual Basic Reference (located at Start >> Programs >> National Instruments >> Vision >> Documentation >> IMAQ Vision for Visual Basic Reference).

Let me know if you have any additional questions on this issue.

Regards,
Scott R.
Applications Engineer
National Instruments

[uts]

Hi,

I like to use IMAQ Histogram, but my LabVIEW lacks this one. Please show me how to display polar histogram from a pixel image. Thank you very much

Thanh Hai Nguyen.

[Allison_S]

Thanh,

    It sounds like you don't have the Vision Development Module -- it is what will give you the IMAQ Histogram VI's, and it sounds like you don't have them.  It is possible to make a histogram of images with the histogram VI's in LabVIEW (Functions >> Mathematics >> Probability & Statistics) though it would require much more programming.  The LabVIEW VI's are made to work with different data types, so you would have to convert the data types.

-Allison S.

Applications Engineering