When estimating a missing depth from its 4-connected neighbors, a
neighbor is accepted if it is within depthErrorRatio of the mean of the
neighbors accepted so far. The tolerance was computed from the running
sum instead of the mean, so it grew to 2x and then 3x the ratio for the
third and fourth neighbor, letting inconsistent depths into the average.
Co-authored-by: matlabbe <[email protected]>
