11 // 'range': a minimum and maximum radius.
12 // 'scale': <= 1.0, to speed up the process.
13 let findRadius (img
: Image<Gray, 'TDepth>) (range: int * int) (scale: float) : int =
14 use scaledImg = if scale = 1. then img else img.Resize(scale, CvEnum.Inter.Area)
17 let r1', r2
' = roundInt (float r1 * scale), roundInt (float r2 * scale)
19 let patternSpectrum = Array.zeroCreate (r2' - r1')
20 let intensityImg = scaledImg.GetSum().Intensity
22 let mutable previous_n = Double.NaN
23 for r in r1' .. r2' do
24 let se = CvInvoke.GetStructuringElement(CvEnum.ElementShape.Ellipse, Size(2 * r, 2 * r), Point(-1, -1))
25 use closed = scaledImg.MorphologyEx(CvEnum.MorphOp.Close, se, Point(-1, -1), 1, CvEnum.BorderType.Replicate, MCvScalar(0.0))
27 let n = closed.GetSum().Intensity
29 if not (Double.IsNaN previous_n)
31 patternSpectrum.[r - r1' - 1] <- abs
(n - previous_n)
34 let max, _
= patternSpectrum |> Array.indexed
|> Array.fold
(fun (iMax
, sMax
) (i
, s
) -> if s
> sMax
then (i
, s
) else (iMax
, sMax
)) (0, Double.MinValue)
36 float (max + r1') / scale |> roundInt