Suppress a point only when both conditions hold simultaneously:
  thresh = Math.max(athresh, M * rthresh)
  (M - val) >= thresh   →   zero the point

athresh enforces a minimum absolute gap; M*rthresh enforces a minimum
relative gap. Math.max means BOTH must be satisfied (either alone is
insufficient). Replaces the previous M>=athresh && val<rthresh*M logic.
Co-authored-by: Claude <claude@elphel.com>