how to use border rejection in jpeg binary image without thresholding?

[pinkman]

This is a problem we encountered in our project recently. We are trying to reject the unwanted parts from the image(outside the border). When we tried to threshold it, the white part of the image becomes black, thus rejecting nothing. 

Please kindly look what is wrong with our vi. Thank you.

In the attachement is an example of the image we are trying to reject its white part outside the border.

[Gopi_nath]

Hi 

Try IMAQ MASK Function. This may helps ypu.

[pinkman]

how can I use IMAQ Mask? I'm not sure how it functions. Thank you.

[Joseph-S]

Hi,

IMAQ Mask is frequently used in vision applications. I would recommend becoming familiar with it by studying the shipping example "Mask Example.vi" which can be found in the LabVIEW example finder. In LabVIEW, go to Help > Find Examples, then browsing by task, navigate to Toolkits and Modules > Vision > Functions. Feel free to post again if you have questions about how the example works and how to apply it to your application.