+ let ellipses = ellipses |> List.map EllipseFlaggedKd
+
+ // 1) Associate touching ellipses with each ellipses and remove ellipse with more than two intersections.
+ let tree = KdTree.Tree.BuildTree ellipses
+ let neighbors (e: EllipseFlaggedKd) : (EllipseFlaggedKd * PointD * PointD) list =
+ if not e.Removed
+ then
+ tree.Search (searchRegion e)
+ // We only keep the ellipses touching 'e'.
+ |> List.choose (fun otherE ->
+ if e <> otherE
+ then
+ match EEOver.EEOverlapArea e otherE with
+ | Some (_, px, _) when px.Length > 2 ->
+ otherE.Removed <- true
+ None
+ | Some (area, px, py) when area > 0.f && px.Length = 2 ->
+ Some (otherE, PointD(px.[0], py.[0]), PointD(px.[1], py.[1]))
+ | _ ->
+ None
+ else
+ None )
+ else
+ []
+
+ // We reverse the list to get the lower score ellipses first.
+ let ellipsesWithNeigbors = ellipses |> List.map (fun e -> e, neighbors e) |> List.rev
+
+ // 2) Remove ellipses touching the edges.
+ for e in ellipses do
+ if e.isOutside w_f h_f then e.Removed <- true
+
+ // 3) Remove ellipses with a high standard deviation (high contrast).
+ let imgData = img.Data
+ let globalStdDeviation = MathNet.Numerics.Statistics.Statistics.PopulationStandardDeviation(seq {
+ for y in 0 .. h - 1 do
+ for x in 0 .. w - 1 do
+ yield float imgData.[y, x, 0] })
+
+ for e in ellipses do
+ if not e.Removed
+ then
+ let shrinkedE = e.Scale 0.9f
+ let minX, minY, maxX, maxY = ellipseWindow shrinkedE
+
+ let stdDeviation = MathNet.Numerics.Statistics.Statistics.StandardDeviation (seq {
+ for y in (if minY < 0 then 0 else minY) .. (if maxY >= h then h - 1 else maxY) do
+ for x in (if minX < 0 then 0 else minX) .. (if maxX >= w then w - 1 else maxX) do
+ if shrinkedE.Contains (float32 x) (float32 y)
+ then
+ yield float imgData.[y, x, 0] })
+
+ if stdDeviation > globalStdDeviation * config.Parameters.standardDeviationMaxRatio then
+ e.Removed <- true
+
+
+ // 4) Remove ellipses with little area.
+ let minArea = config.RBCRadius.MinArea
+ for e, neighbors in ellipsesWithNeigbors do
+ if not e.Removed
+ then
+ let minX, minY, maxX, maxY = ellipseWindow e
+
+ let mutable area = 0
+ for y in (if minY < 0 then 0 else minY) .. (if maxY >= h then h - 1 else maxY) do
+ for x in (if minX < 0 then 0 else minX) .. (if maxX >= w then w - 1 else maxX) do
+ let p = PointD(float32 x, float32 y)
+ if pixelOwnedByE p e (neighbors |> List.choose (fun (otherE, p1, p2) -> if otherE.Removed then None else Some (otherE :> Ellipse, Utils.lineFromTwoPoints p1 p2)))
+ then
+ area <- area + 1
+
+ if area < int minArea
+ then
+ e.Removed <- true
+
+ // 5) Define pixels associated to each ellipse and create the cells.