[Greg McKaskle]

The example code uses the bounding box as an approximation.

If you want to make a multi-pass measurement, once you have the bounding box, you can reinspect the blob, or perhaps the original image to locate the precise edges. Doing the edge detection on the entire image is expensive. Doing it on the area known to contain the target should be pretty cheap. Personally, I think the example code should be careful not to solve too much of the problem.

Back to the original problem, again, it this instance, you shouldn't really need to crop or copy the image, but you should normally be able to use an RIO that is constructed from the rectangle, mask, or other geometric info.

Greg McKaskle