VBAI Threshold Step should work on ROI, not just "full image"

[Jeff_Spaulding]

it would be handy if the VBAI "Threshold Image" step could operate on just a selected region of interest instead of only working on the full image.

[varga.sm]

The work around is a lot of steps if you need to programmically set a threshold.  This would also help speed up the inspection when using large images and needed to threshold only a small region.

[Brad]

This is a good idea. I'm reposting this as a Vision Development Module Idea since we would need this implemented in the Vision function before we could implement it in VBAI.