Stippling with sizes from average intensities after CAH

Do CAH and calculate the sizes of each stipple based on the average intensities. Redraw the stipples. If the new stipple covers the old pixels after CAH, the old pixels won't be stipples any more.

(A) It seems it keeps some edges after half procedure.

(A) Half pixels are processed.
(B)Zoom in from (C)

(C) All pixels drawn as stipples