module ImgTools open System open System.Drawing open System.Collections.Generic open Emgu.CV open Emgu.CV.Structure open Utils // Normalize image values between 0uy and 255uy. let normalizeAndConvert (img: Image) : Image = let min = ref [| 0.0 |] let minLocation = ref <| [| Point() |] let max = ref [| 0.0 |] let maxLocation = ref <| [| Point() |] img.MinMax(min, max, minLocation, maxLocation) ((img - (!min).[0]) / ((!max).[0] - (!min).[0]) * 255.0).Convert() let gaussianFilter (img : Image<'TColor, 'TDepth>) (standardDeviation : float) : Image<'TColor, 'TDepth> = let size = 2 * int (ceil (4.0 * standardDeviation)) + 1 img.SmoothGaussian(size, size, standardDeviation, standardDeviation) // Zhang and Suen algorithm. // Modify 'mat' in place. let thin (mat: Matrix) = let neighbors = [| (-1, 0) // p2 (-1, 1) // p3 ( 0, 1) // p4 ( 1, 1) // p5 ( 1, 0) // p6 ( 1, -1) // p7 ( 0, -1) // p8 (-1, -1) |] // p9 let w = mat.Width let h = mat.Height let mutable data1 = mat.Data let mutable data2 = Array2D.zeroCreate h w // Return the list of neighbor values. let neighborsValues (p1i, p1j) = Array.map (fun (ni, nj) -> let pi = p1i + ni let pj = p1j + nj if pi < 0 || pi >= h || pj < 0 || pj >= w then 0uy else data1.[pi, pj] ) neighbors // Return the number of 01 pattern in 'values' in a circular way. let pattern01 (values: byte[]) = let mutable nb = 0 let mutable lastValue = 255uy for v in values do if lastValue = 0uy && v = 1uy then nb <- nb + 1 lastValue <- v if lastValue = 0uy && values.[0] = 1uy then nb <- nb + 1 nb let mutable pixelChanged = true let mutable oddIteration = true while pixelChanged do pixelChanged <- false for i in 0..h-1 do for j in 0..w-1 do if data1.[i, j] = 1uy then let values = neighborsValues (i, j) let s = Array.reduce (+) values if s >= 2uy && s <= 6uy && pattern01 values = 1 && (not oddIteration || (values.[0] * values.[2] * values.[4] = 0uy && values.[2] * values.[4] * values.[6] = 0uy)) && // Odd iteration. (oddIteration || (values.[0] * values.[2] * values.[6] = 0uy && values.[0] * values.[4] * values.[6] = 0uy)) // Even iterations. then data2.[i, j] <- 0uy pixelChanged <- true else data2.[i, j] <- 1uy else data2.[i, j] <- 0uy oddIteration <- not oddIteration let tmp = data1 data1 <- data2 data2 <- tmp // Remove all 8-connected pixels with an area equal or greater than 'areaSize'. // Modify 'mat' in place. let removeArea (mat: Matrix) (areaSize: int) = let neighbors = [| (-1, 0) // p2 (-1, 1) // p3 ( 0, 1) // p4 ( 1, 1) // p5 ( 1, 0) // p6 ( 1, -1) // p7 ( 0, -1) // p8 (-1, -1) |] // p9 let mat' = new Matrix(mat.Size) let w = mat'.Width let h = mat'.Height mat.CopyTo(mat') let data = mat.Data let data' = mat'.Data for i in 0..h-1 do for j in 0..w-1 do if data'.[i, j] = 1uy then let neighborhood = List<(int*int)>() let neighborsToCheck = List<(int*int)>() neighborsToCheck.Add((i, j)) data'.[i, j] <- 0uy let pop (l: List<'a>) : 'a = let n = l.[l.Count - 1] l.RemoveAt(l.Count - 1) n while neighborsToCheck.Count > 0 do let (ci, cj) = pop neighborsToCheck neighborhood.Add((ci, cj)) for (ni, nj) in neighbors do let pi = ci + ni let pj = cj + nj if pi >= 0 && pi < h && pj >= 0 && pj < w && data'.[pi, pj] = 1uy then neighborsToCheck.Add((pi, pj)) data'.[pi, pj] <- 0uy if neighborhood.Count <= areaSize then for (ni, nj) in neighborhood do data.[ni, nj] <- 0uy let saveImg (img: Image<'TColor, 'TDepth>) (name: string) = img.Save("output/" + name) let saveMat (mat: Matrix<'TDepth>) (name: string) = use img = new Image(mat.Size) mat.CopyTo(img) saveImg img name (*let drawEllipse (img: Image<'TColor, 'TDepth>) (e: Types.Ellipse) (color: 'TColor) = let e' = Ellipse(PointF(float32 e.cx, float32 e.cy), SizeF(2.0f * float32 e.a, 2.0f * float32 e.b), float32 e.alpha) img.Draw(e', color)*) let drawLine (img: Image<'TColor, 'TDepth>) (color: 'TColor) (x0: float) (y0: float) (x1: float) (y1: float) = let x0, y0, x1, y1 = roundInt(x0), roundInt(y0), roundInt(x1), roundInt(y1) img.Draw(LineSegment2D(Point(x0, y0), Point(x1, y1)), color, 1); let drawEllipse (img: Image<'TColor, 'TDepth>) (e: Types.Ellipse) (color: 'TColor) = let cosAlpha = cos e.Alpha let sinAlpha = sin e.Alpha let mutable x0 = 0.0 let mutable y0 = 0.0 let mutable first_iteration = true let n = 40 let thetaIncrement = 2.0 * Math.PI / (float n) for theta in 0.0 .. thetaIncrement .. 2.0 * Math.PI do let cosTheta = cos theta let sinTheta = sin theta let x = e.Cx + cosAlpha * e.A * cosTheta - sinAlpha * e.B * sinTheta let y = e.Cy + sinAlpha * e.A * cosTheta + cosAlpha * e.B * sinTheta if not first_iteration then drawLine img color x0 y0 x y else first_iteration <- false x0 <- x y0 <- y let drawEllipses (img: Image<'TColor, 'TDepth>) (ellipses: Types.Ellipse list) (color: 'TColor) = List.iter (fun e -> drawEllipse img e color) ellipses