Each transform, drawn.

Difference from the west neighbour.

Difference from the north neighbour.

The plane W + N − NW.

Median edge detector, clamps across edges.

Floor average of W and N.

Frozen weighted predictor, P = W + K.

Splits one stream into two lanes by position.

Splits the holes out into a validity mask.

A flat bound on a uniform grid.

A relative bound, the same per cent everywhere.

A shot-noise bound, wider where the noise is.