Peano scanning of arbitrary size images

Discrete space-filling curves are not uniquely defined. In addition to the condition that the curve must pass all the points of the array only once, continuously, it is necessary to add some critera to select the best curves. The authors aim is to preserve two-dimensional continuity as much as possible. The weighted sum of the distances of the points in the curve is minimized, where the weights are inversely proportional to the spatial distance between the points. However, the minimum is not unique. Particularly, space-filling curves always come on symmetric pairs. The generation of a near optimal space-filling curve is done hierarchically