Parasitemia/ParasitemiaCore/Granulometry.fs

   1 module ParasitemiaCore.Granulometry
   2
   3 open System
   4 open System.Drawing
   5
   6 open Emgu.CV
   7 open Emgu.CV.Structure
   8
   9 open Utils
  10
  11 /// <summary>
  12 /// Granulometry by closing on the image 'img' by testing circle structrual elements with radius range in 'range'.
  13 /// </summary>
  14 /// <param name="img"></param>
  15 /// <param name="range">Minimum radius * maximum radius</param>
  16 /// <param name="scale">le 1.0, to speed up the process.</param>
  17 let findRadiusByClosing (img: Image<Gray, 'TDepth>) (range: int * int) (scale: float) (useOctagon: bool) : int =
  18     use scaledImg = if scale = 1. then img else img.Resize(scale, CvEnum.Inter.Area)
  19
  20     let r1, r2 = range
  21     let r1', r2' = roundInt (float r1 * scale), roundInt (float r2 * scale)
  22
  23     let patternSpectrum = Array.zeroCreate (r2' - r1')
  24     let intensityImg = scaledImg.GetSum().Intensity
  25
  26     // 's' must be odd.
  27     let octagon (s: int) : Mat =
  28         if s % 2 = 0 then failwith "s must be odd"
  29         let m = new Matrix<byte>(Array2D.create s s 1uy)
  30         let r = (float s) / (Math.Sqrt 2. + 2.) |> roundInt
  31         for i in 0 .. r - 1 do
  32             for j in 0 .. r - 1 do
  33                 if i + j < r
  34                 then
  35                     m.[i, j] <- 0uy
  36                     m.[s - i - 1, j] <- 0uy
  37                     m.[i, s - j - 1] <- 0uy
  38                     m.[s - i - 1, s - j - 1] <- 0uy
  39         m.Mat
  40
  41     let mutable previous_n = Double.NaN
  42     for r in r1' .. r2' do
  43         let se = if useOctagon
  44                  then octagon (2 * r - 1) // It doesnd't speed up the process.
  45                  else CvInvoke.GetStructuringElement(CvEnum.ElementShape.Ellipse, Size(2 * r, 2 * r), Point(-1, -1))
  46
  47         use closed = scaledImg.MorphologyEx(CvEnum.MorphOp.Close, se, Point(-1, -1), 1, CvEnum.BorderType.Replicate, MCvScalar(0.0))
  48
  49         let n = closed.GetSum().Intensity
  50
  51         if not (Double.IsNaN previous_n)
  52         then
  53             patternSpectrum.[r - r1' - 1] <- abs (n - previous_n)
  54         previous_n <- n
  55
  56     let max, _ = patternSpectrum |> Array.indexed |> Array.fold (fun (iMax, sMax) (i, s) -> if s > sMax then (i, s) else (iMax, sMax)) (0, Double.MinValue)
  57
  58     float (max + r1') / scale |> roundInt
  59
  60 /// <summary>
  61 /// Granulometry by area closing on the image 'img' by testing the circle area into the given radius range.
  62 /// </summary>
  63 let findRadiusByAreaClosing (img: Image<Gray, float32>) (radiusRange: int * int) : int =
  64     let r1, r2 = radiusRange
  65
  66     if r1 > r2
  67     then failwithf "'radiusRange' invalid : %A" radiusRange
  68
  69     use imgCopy = img.Copy()
  70
  71     let mutable maxDiff = 0.f
  72     let mutable max_r = r1
  73
  74     ImgTools.areaCloseFWithFun imgCopy [ for r in r1 .. r2 -> Math.PI * float r ** 2. |> roundInt, r ] (fun r diff ->
  75         if r <> r1 && diff > maxDiff
  76         then
  77             maxDiff <- diff
  78             max_r <- r - 1)
  79     max_r
  80