Parasitemia/Parasitemia/ParasitesMarker.fs

   1 module ParasitesMarker
   2
   3 open System.Drawing
   4
   5 open Emgu.CV
   6 open Emgu.CV.Structure
   7
   8 type Result = {
   9     darkStain: Image<Gray, byte>
  10     stain: Image<Gray, byte>
  11     infection: Image<Gray, byte> }
  12
  13 // Create three binary markers :
  14 // * 'Dark stain' corresponds to the colored pixel, it's independent of the size of the areas.
  15 // * 'Stain' corresponds to the stain around the parasites.
  16 // * 'Infection' corresponds to the parasite. It shouldn't contain thrombocytes.
  17 let find (green: Image<Gray, float32>) (filteredGreen: Image<Gray, float32>) (kmediansResult: KMedians.Result) (config: Config.Config) : Result =
  18
  19     let green = ImgTools.gaussianFilter green 1.0
  20
  21     // We use the filtered image to find the dark stain.
  22     let { KMedians.fg = fg; KMedians.median_bg = median_bg; KMedians.median_fg = median_fg; KMedians.d_fg = d_fg } = kmediansResult
  23     let darkStain = d_fg.Cmp(median_bg * config.darkStainLevel, CvEnum.CmpType.GreaterThan)
  24     darkStain._And(filteredGreen.Cmp(median_fg, CvEnum.CmpType.LessThan))
  25     darkStain._And(fg)
  26
  27     let fgFloat = (fg / 255.0).Convert<Gray, float32>()
  28     let greenWithoutBg = green.Copy()
  29     greenWithoutBg.SetValue(Gray(0.0), fg.Not())
  30
  31     let findSmears (sigma: float) (level: float) : Image<Gray, byte> =
  32         let greenWithoutBgSmoothed = ImgTools.gaussianFilter greenWithoutBg sigma
  33         let fgSmoothed = ImgTools.gaussianFilter fgFloat sigma
  34
  35         let smears = (greenWithoutBg.Mul(fgSmoothed)).Cmp(greenWithoutBgSmoothed.Mul(level), CvEnum.CmpType.LessThan)
  36         smears._And(fg)
  37         smears
  38
  39     { darkStain = darkStain;
  40       stain = findSmears config.stainSigma config.stainLevel
  41       infection = findSmears config.infectionSigma config.infectionLevel }
  42
  43
  44
  45