Machine vision: overlooking shadow and light splotches on surfaces

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[Audio Version]

Following is another in the aforementioned series of ad hoc journal entries I've been keeping of my thoughts on machine vision.

Shadows and light splotches that fall on even perfectly smooth surfaces really trip up systems designed to detect objects by finding contiguous surfaces. We don't seem to be fooled by such issues very often.

We are fooled when there are ambiguities in what we see. Perhaps understanding what makes one situation ambiguous versus another will help isolate what differentiates the two for the benefit of codification.

Looking at a picture I took looking down a tree-lined sidewalk, I found a great example of the issue. Shadows of trees fall on the sidewalk, creating a fairly smooth, two-tone division between shadowed and non-shadowed portions. I see a continuous sidewalk.

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