(This article was first published on me nugget, and kindly contributed to R-bloggers)
I found the following post regarding the anomalous metal object observed in a Curiosity Rover photo to be fascinating - specifically, the clever ways that some programmers used for filtering the image for the object. The following answer on mathematica.stackexchange.com was especially illuminating for its use of a multivariate distribution to describe the color channels for a test region of "sand". This distribution was subsequently used to assess if the rest of the image colors belonged to the same distribution.
I tried a different approach, using a Principal Component Analysis (PCA) filter (above), also based on a region of sand. I believe the PCs can be understood in the following way: the PCs represent dominant rgb colors (below), while the loadings are indicate the intensity of the color.
I tried a different approach, using a Principal Component Analysis (PCA) filter (above), also based on a region of sand. I believe the PCs can be understood in the following way: the PCs represent dominant rgb colors (below), while the loadings are indicate the intensity of the color.
Code to reproduce:
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Image may be NSFW.
Clik here to view.
Clik here to view.
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