C # + OpenCvSharp, Pontuação: 2
Esta é a minha segunda tentativa. É bem diferente da minha primeira tentativa , que é muito mais simples, por isso estou publicando como uma solução separada.
A idéia básica é identificar e rotular cada grão individual por um ajuste de elipse iterativo. Em seguida, remova os pixels desse grão da origem e tente encontrar o próximo grão, até que cada pixel tenha sido rotulado.
Esta não é a solução mais bonita. É um porco gigante com 600 linhas de código. Ele precisa de 1,5 minutos para a maior imagem. E realmente peço desculpas pelo código confuso.
Existem tantos parâmetros e maneiras de pensar nisso que tenho muito medo de ajustar meu programa para as 10 imagens de amostra. A pontuação final de 2 é quase definitivamente um caso de sobreajuste: eu tenho dois parâmetros,, average grain size in pixele minimum ratio of pixel / elipse_area, e no final simplesmente exaurei todas as combinações desses dois parâmetros até obter a pontuação mais baixa. Não tenho certeza se isso é tudo o que kosher com as regras deste desafio.
average_grain_size_in_pixel = 2530
pixel / elipse_area >= 0.73
Mas mesmo sem essas embreagens, os resultados são bastante bons. Sem um tamanho fixo de grão ou proporção de pixels, simplesmente estimando o tamanho médio de grão a partir das imagens de treinamento, a pontuação ainda é 27.
E recebo como resultado não apenas o número, mas a posição, orientação e forma reais de cada grão. há um pequeno número de grãos com etiquetas incorretas, mas no geral a maioria dos rótulos corresponde exatamente aos grãos reais:
A 
B 
C 
D 
E
F 
G 
H 
I 
J
(clique em cada imagem para obter a versão em tamanho normal)
Após esta etapa de rotulagem, meu programa analisa cada granulação individual e estima com base no número de pixels e na proporção pixel / elipse-área, se isso é
- um único grão (+1)
- vários grãos classificados incorretamente como um (+ X)
- um blob muito pequeno para ser um grão (+0)
As pontuações de erro para cada imagem são
A:0; B:0; C:0; D:0; E:2; F:0; G:0 ; H:0; I:0, J:0
No entanto, o erro real é provavelmente um pouco maior. Alguns erros na mesma imagem se cancelam. A imagem H, em particular, possui alguns grãos mal rotulados, enquanto na imagem E os rótulos estão na maioria corretos
O conceito é um pouco artificial:
Primeiro, o primeiro plano é separado via otsu-thresholding no canal de saturação (veja minha resposta anterior para detalhes)
repita até que não haja mais pixels:
- selecione o maior blob
escolha 10 pixels de borda aleatórios neste blob como posições iniciais de um grão
para cada ponto de partida
Entre os 10 grãos ajustados, escolha o melhor grão de acordo com a forma, número de pixels da aresta. Descartar os outros
remova todos os pixels desse grão da imagem de origem e repita
por fim, leia a lista de grãos encontrados e conte cada grão como 1 grão, 0 grão (muito pequeno) ou 2 grãos (muito grande)
Um dos meus principais problemas era que eu não queria implementar uma métrica de distância de ponto de elipse completa, pois calcular isso por si só é um processo iterativo complicado. Então, usei várias soluções alternativas usando as funções OpenCV Ellipse2Poly e FitEllipse, e os resultados não são muito bonitos.
Aparentemente, eu também quebrei o limite de tamanho para o codegolf.
Uma resposta é limitada a 30000 caracteres, atualmente estou em 34000. Portanto, vou ter que diminuir um pouco o código abaixo.
O código completo pode ser visto em http://pastebin.com/RgM7hMxq
Desculpe por isso, eu não sabia que havia um limite de tamanho.
class Program
{
static void Main(string[] args)
{
// Due to size constraints, I removed the inital part of my program that does background separation. For the full source, check the link, or see my previous program.
// list of recognized grains
List<Grain> grains = new List<Grain>();
Random rand = new Random(4); // determined by fair dice throw, guaranteed to be random
// repeat until we have found all grains (to a maximum of 10000)
for (int numIterations = 0; numIterations < 10000; numIterations++ )
{
// erode the image of the remaining foreground pixels, only big blobs can be grains
foreground.Erode(erodedForeground,null,7);
// pick a number of starting points to fit grains
List<CvPoint> startPoints = new List<CvPoint>();
using (CvMemStorage storage = new CvMemStorage())
using (CvContourScanner scanner = new CvContourScanner(erodedForeground, storage, CvContour.SizeOf, ContourRetrieval.List, ContourChain.ApproxNone))
{
if (!scanner.Any()) break; // no grains left, finished!
// search for grains within the biggest blob first (this is arbitrary)
var biggestBlob = scanner.OrderByDescending(c => c.Count()).First();
// pick 10 random edge pixels
for (int i = 0; i < 10; i++)
{
startPoints.Add(biggestBlob.ElementAt(rand.Next(biggestBlob.Count())).Value);
}
}
// for each starting point, try to fit a grain there
ConcurrentBag<Grain> candidates = new ConcurrentBag<Grain>();
Parallel.ForEach(startPoints, point =>
{
Grain candidate = new Grain(point);
candidate.Fit(foreground);
candidates.Add(candidate);
});
Grain grain = candidates
.OrderByDescending(g=>g.Converged) // we don't want grains where the iterative fit did not finish
.ThenBy(g=>g.IsTooSmall) // we don't want tiny grains
.ThenByDescending(g => g.CircumferenceRatio) // we want grains that have many edge pixels close to the fitted elipse
.ThenBy(g => g.MeanSquaredError)
.First(); // we only want the best fit among the 10 candidates
// count the number of foreground pixels this grain has
grain.CountPixel(foreground);
// remove the grain from the foreground
grain.Draw(foreground,CvColor.Black);
// add the grain to the colection fo found grains
grains.Add(grain);
grain.Index = grains.Count;
// draw the grain for visualisation
grain.Draw(display, CvColor.Random());
grain.DrawContour(display, CvColor.Random());
grain.DrawEllipse(display, CvColor.Random());
//display.SaveImage("10-foundGrains.png");
}
// throw away really bad grains
grains = grains.Where(g => g.PixelRatio >= 0.73).ToList();
// estimate the average grain size, ignoring outliers
double avgGrainSize =
grains.OrderBy(g => g.NumPixel).Skip(grains.Count/10).Take(grains.Count*9/10).Average(g => g.NumPixel);
//ignore the estimated grain size, use a fixed size
avgGrainSize = 2530;
// count the number of grains, using the average grain size
double numGrains = grains.Sum(g => Math.Round(g.NumPixel * 1.0 / avgGrainSize));
// get some statistics
double avgWidth = grains.Where(g => Math.Round(g.NumPixel * 1.0 / avgGrainSize) == 1).Average(g => g.Width);
double avgHeight = grains.Where(g => Math.Round(g.NumPixel * 1.0 / avgGrainSize) == 1).Average(g => g.Height);
double avgPixelRatio = grains.Where(g => Math.Round(g.NumPixel * 1.0 / avgGrainSize) == 1).Average(g => g.PixelRatio);
int numUndersized = grains.Count(g => Math.Round(g.NumPixel * 1.0 / avgGrainSize) < 1);
int numOversized = grains.Count(g => Math.Round(g.NumPixel * 1.0 / avgGrainSize) > 1);
double avgWidthUndersized = grains.Where(g => Math.Round(g.NumPixel * 1.0 / avgGrainSize) < 1).Select(g=>g.Width).DefaultIfEmpty(0).Average();
double avgHeightUndersized = grains.Where(g => Math.Round(g.NumPixel * 1.0 / avgGrainSize) < 1).Select(g => g.Height).DefaultIfEmpty(0).Average();
double avgGrainSizeUndersized = grains.Where(g => Math.Round(g.NumPixel * 1.0 / avgGrainSize) < 1).Select(g => g.NumPixel).DefaultIfEmpty(0).Average();
double avgPixelRatioUndersized = grains.Where(g => Math.Round(g.NumPixel * 1.0 / avgGrainSize) < 1).Select(g => g.PixelRatio).DefaultIfEmpty(0).Average();
double avgWidthOversized = grains.Where(g => Math.Round(g.NumPixel * 1.0 / avgGrainSize) > 1).Select(g => g.Width).DefaultIfEmpty(0).Average();
double avgHeightOversized = grains.Where(g => Math.Round(g.NumPixel * 1.0 / avgGrainSize) > 1).Select(g => g.Height).DefaultIfEmpty(0).Average();
double avgGrainSizeOversized = grains.Where(g => Math.Round(g.NumPixel * 1.0 / avgGrainSize) > 1).Select(g => g.NumPixel).DefaultIfEmpty(0).Average();
double avgPixelRatioOversized = grains.Where(g => Math.Round(g.NumPixel * 1.0 / avgGrainSize) > 1).Select(g => g.PixelRatio).DefaultIfEmpty(0).Average();
Console.WriteLine("===============================");
Console.WriteLine("Grains: {0}|{1:0.} of {2} (e{3}), size {4:0.}px, {5:0.}x{6:0.} {7:0.000} undersized:{8} oversized:{9} {10:0.0} minutes {11:0.0} s per grain",grains.Count,numGrains,expectedGrains[fileNo],expectedGrains[fileNo]-numGrains,avgGrainSize,avgWidth,avgHeight, avgPixelRatio,numUndersized,numOversized,watch.Elapsed.TotalMinutes, watch.Elapsed.TotalSeconds/grains.Count);
// draw the description for each grain
foreach (Grain grain in grains)
{
grain.DrawText(avgGrainSize, display, CvColor.Black);
}
display.SaveImage("10-foundGrains.png");
display.SaveImage("X-" + file + "-foundgrains.png");
}
}
}
}
public class Grain
{
private const int MIN_WIDTH = 70;
private const int MAX_WIDTH = 130;
private const int MIN_HEIGHT = 20;
private const int MAX_HEIGHT = 35;
private static CvFont font01 = new CvFont(FontFace.HersheyPlain, 0.5, 1);
private Random random = new Random(4); // determined by fair dice throw; guaranteed to be random
/// <summary> center of grain </summary>
public CvPoint2D32f Position { get; private set; }
/// <summary> Width of grain (always bigger than height)</summary>
public float Width { get; private set; }
/// <summary> Height of grain (always smaller than width)</summary>
public float Height { get; private set; }
public float MinorRadius { get { return this.Height / 2; } }
public float MajorRadius { get { return this.Width / 2; } }
public double Angle { get; private set; }
public double AngleRad { get { return this.Angle * Math.PI / 180; } }
public int Index { get; set; }
public bool Converged { get; private set; }
public int NumIterations { get; private set; }
public double CircumferenceRatio { get; private set; }
public int NumPixel { get; private set; }
public List<EllipsePoint> EdgePoints { get; private set; }
public double MeanSquaredError { get; private set; }
public double PixelRatio { get { return this.NumPixel / (Math.PI * this.MajorRadius * this.MinorRadius); } }
public bool IsTooSmall { get { return this.Width < MIN_WIDTH || this.Height < MIN_HEIGHT; } }
public Grain(CvPoint2D32f position)
{
this.Position = position;
this.Angle = 0;
this.Width = 10;
this.Height = 10;
this.MeanSquaredError = double.MaxValue;
}
/// <summary> fit a single rice grain of elipsoid shape </summary>
public void Fit(CvMat img)
{
// distance between the sampled points on the elipse circumference in degree
int angularResolution = 1;
// how many times did the fitted ellipse not change significantly?
int numConverged = 0;
// number of iterations for this fit
int numIterations;
// repeat until the fitted ellipse does not change anymore, or the maximum number of iterations is reached
for (numIterations = 0; numIterations < 100 && !this.Converged; numIterations++)
{
// points on an ideal ellipse
CvPoint[] points;
Cv.Ellipse2Poly(this.Position, new CvSize2D32f(MajorRadius, MinorRadius), Convert.ToInt32(this.Angle), 0, 359, out points,
angularResolution);
// points on the edge of foregroudn to background, that are close to the elipse
CvPoint?[] edgePoints = new CvPoint?[points.Length];
// remeber if the previous pixel in a given direction was foreground or background
bool[] prevPixelWasForeground = new bool[points.Length];
// when the first edge pixel is found, this value is updated
double firstEdgePixelOffset = 200;
// from the center of the elipse towards the outside:
for (float offset = -this.MajorRadius + 1; offset < firstEdgePixelOffset + 20; offset++)
{
// draw an ellipse with the given offset
Cv.Ellipse2Poly(this.Position, new CvSize2D32f(MajorRadius + offset, MinorRadius + (offset > 0 ? offset : MinorRadius / MajorRadius * offset)), Convert.ToInt32(this.Angle), 0,
359, out points, angularResolution);
// for each angle
Parallel.For(0, points.Length, i =>
{
if (edgePoints[i].HasValue) return; // edge for this angle already found
// check if the current pixel is foreground
bool foreground = points[i].X < 0 || points[i].Y < 0 || points[i].X >= img.Cols || points[i].Y >= img.Rows
? false // pixel outside of image borders is always background
: img.Get2D(points[i].Y, points[i].X).Val0 > 0;
if (prevPixelWasForeground[i] && !foreground)
{
// found edge pixel!
edgePoints[i] = points[i];
// if this is the first edge pixel we found, remember its offset. the other pixels cannot be too far away, so we can stop searching soon
if (offset < firstEdgePixelOffset && offset > 0) firstEdgePixelOffset = offset;
}
prevPixelWasForeground[i] = foreground;
});
}
// estimate the distance of each found edge pixel from the ideal elipse
// this is a hack, since the actual equations for estimating point-ellipse distnaces are complicated
Cv.Ellipse2Poly(this.Position, new CvSize2D32f(MajorRadius, MinorRadius), Convert.ToInt32(this.Angle), 0, 360,
out points, angularResolution);
var pointswithDistance =
edgePoints.Select((p, i) => p.HasValue ? new EllipsePoint(p.Value, points[i], this.Position) : null)
.Where(p => p != null).ToList();
if (pointswithDistance.Count == 0)
{
Console.WriteLine("no points found! should never happen! ");
break;
}
// throw away all outliers that are too far outside the current ellipse
double medianSignedDistance = pointswithDistance.OrderBy(p => p.SignedDistance).ElementAt(pointswithDistance.Count / 2).SignedDistance;
var goodPoints = pointswithDistance.Where(p => p.SignedDistance < medianSignedDistance + 15).ToList();
// do a sort of ransack fit with the inlier points to find a new better ellipse
CvBox2D bestfit = ellipseRansack(goodPoints);
// check if the fit has converged
if (Math.Abs(this.Angle - bestfit.Angle) < 3 && // angle has not changed much (<3°)
Math.Abs(this.Position.X - bestfit.Center.X) < 3 && // position has not changed much (<3 pixel)
Math.Abs(this.Position.Y - bestfit.Center.Y) < 3)
{
numConverged++;
}
else
{
numConverged = 0;
}
if (numConverged > 2)
{
this.Converged = true;
}
//Console.WriteLine("Iteration {0}, delta {1:0.000} {2:0.000} {3:0.000} {4:0.000}-{5:0.000} {6:0.000}-{7:0.000} {8:0.000}-{9:0.000}",
// numIterations, Math.Abs(this.Angle - bestfit.Angle), Math.Abs(this.Position.X - bestfit.Center.X), Math.Abs(this.Position.Y - bestfit.Center.Y), this.Angle, bestfit.Angle, this.Position.X, bestfit.Center.X, this.Position.Y, bestfit.Center.Y);
double msr = goodPoints.Sum(p => p.Distance * p.Distance) / goodPoints.Count;
// for drawing the polygon, filter the edge points more strongly
if (goodPoints.Count(p => p.SignedDistance < 5) > goodPoints.Count / 2)
goodPoints = goodPoints.Where(p => p.SignedDistance < 5).ToList();
double cutoff = goodPoints.Select(p => p.Distance).OrderBy(d => d).ElementAt(goodPoints.Count * 9 / 10);
goodPoints = goodPoints.Where(p => p.SignedDistance <= cutoff + 1).ToList();
int numCertainEdgePoints = goodPoints.Count(p => p.SignedDistance > -2);
this.CircumferenceRatio = numCertainEdgePoints * 1.0 / points.Count();
this.Angle = bestfit.Angle;
this.Position = bestfit.Center;
this.Width = bestfit.Size.Width;
this.Height = bestfit.Size.Height;
this.EdgePoints = goodPoints;
this.MeanSquaredError = msr;
}
this.NumIterations = numIterations;
//Console.WriteLine("Grain found after {0,3} iterations, size={1,3:0.}x{2,3:0.} pixel={3,5} edgePoints={4,3} msr={5,2:0.00000}", numIterations, this.Width,
// this.Height, this.NumPixel, this.EdgePoints.Count, this.MeanSquaredError);
}
/// <summary> a sort of ransakc fit to find the best ellipse for the given points </summary>
private CvBox2D ellipseRansack(List<EllipsePoint> points)
{
using (CvMemStorage storage = new CvMemStorage(0))
{
// calculate minimum bounding rectangle
CvSeq<CvPoint> fullPointSeq = CvSeq<CvPoint>.FromArray(points.Select(p => p.Point), SeqType.EltypePoint, storage);
var boundingRect = fullPointSeq.MinAreaRect2();
// the initial candidate is the previously found ellipse
CvBox2D bestEllipse = new CvBox2D(this.Position, new CvSize2D32f(this.Width, this.Height), (float)this.Angle);
double bestError = calculateEllipseError(points, bestEllipse);
Queue<EllipsePoint> permutation = new Queue<EllipsePoint>();
if (points.Count >= 5) for (int i = -2; i < 20; i++)
{
CvBox2D ellipse;
if (i == -2)
{
// first, try the ellipse described by the boundingg rect
ellipse = boundingRect;
}
else if (i == -1)
{
// then, try the best-fit ellipsethrough all points
ellipse = fullPointSeq.FitEllipse2();
}
else
{
// then, repeatedly fit an ellipse through a random sample of points
// pick some random points
if (permutation.Count < 5) permutation = new Queue<EllipsePoint>(permutation.Concat(points.OrderBy(p => random.Next())));
CvSeq<CvPoint> pointSeq = CvSeq<CvPoint>.FromArray(permutation.Take(10).Select(p => p.Point), SeqType.EltypePoint, storage);
for (int j = 0; j < pointSeq.Count(); j++) permutation.Dequeue();
// fit an ellipse through these points
ellipse = pointSeq.FitEllipse2();
}
// assure that the width is greater than the height
ellipse = NormalizeEllipse(ellipse);
// if the ellipse is too big for agrain, shrink it
ellipse = rightSize(ellipse, points.Where(p => isOnEllipse(p.Point, ellipse, 10, 10)).ToList());
// sometimes the ellipse given by FitEllipse2 is totally off
if (boundingRect.Center.DistanceTo(ellipse.Center) > Math.Max(boundingRect.Size.Width, boundingRect.Size.Height) * 2)
{
// ignore this bad fit
continue;
}
// estimate the error
double error = calculateEllipseError(points, ellipse);
if (error < bestError)
{
// found a better ellipse!
bestError = error;
bestEllipse = ellipse;
}
}
return bestEllipse;
}
}
/// <summary> The proper thing to do would be to use the actual distance of each point to the elipse.
/// However that formula is complicated, so ... </summary>
private double calculateEllipseError(List<EllipsePoint> points, CvBox2D ellipse)
{
const double toleranceInner = 5;
const double toleranceOuter = 10;
int numWrongPoints = points.Count(p => !isOnEllipse(p.Point, ellipse, toleranceInner, toleranceOuter));
double ratioWrongPoints = numWrongPoints * 1.0 / points.Count;
int numTotallyWrongPoints = points.Count(p => !isOnEllipse(p.Point, ellipse, 10, 20));
double ratioTotallyWrongPoints = numTotallyWrongPoints * 1.0 / points.Count;
// this pseudo-distance is biased towards deviations on the major axis
double pseudoDistance = Math.Sqrt(points.Sum(p => Math.Abs(1 - ellipseMetric(p.Point, ellipse))) / points.Count);
// primarily take the number of points far from the elipse border as an error metric.
// use pseudo-distance to break ties between elipses with the same number of wrong points
return ratioWrongPoints * 1000 + ratioTotallyWrongPoints+ pseudoDistance / 1000;
}
/// <summary> shrink an ellipse if it is larger than the maximum grain dimensions </summary>
private static CvBox2D rightSize(CvBox2D ellipse, List<EllipsePoint> points)
{
if (ellipse.Size.Width < MAX_WIDTH && ellipse.Size.Height < MAX_HEIGHT) return ellipse;
// elipse is bigger than the maximum grain size
// resize it so it fits, while keeping one edge of the bounding rectangle constant
double desiredWidth = Math.Max(10, Math.Min(MAX_WIDTH, ellipse.Size.Width));
double desiredHeight = Math.Max(10, Math.Min(MAX_HEIGHT, ellipse.Size.Height));
CvPoint2D32f average = points.Average();
// get the corners of the surrounding bounding box
var corners = ellipse.BoxPoints().ToList();
// find the corner that is closest to the center of mass of the points
int i0 = ellipse.BoxPoints().Select((point, index) => new { point, index }).OrderBy(p => p.point.DistanceTo(average)).First().index;
CvPoint p0 = corners[i0];
// find the two corners that are neighbouring this one
CvPoint p1 = corners[(i0 + 1) % 4];
CvPoint p2 = corners[(i0 + 3) % 4];
// p1 is the next corner along the major axis (widht), p2 is the next corner along the minor axis (height)
if (p0.DistanceTo(p1) < p0.DistanceTo(p2))
{
CvPoint swap = p1;
p1 = p2;
p2 = swap;
}
// calculate the three other corners with the desired widht and height
CvPoint2D32f edge1 = (p1 - p0);
CvPoint2D32f edge2 = p2 - p0;
double edge1Length = Math.Max(0.0001, p0.DistanceTo(p1));
double edge2Length = Math.Max(0.0001, p0.DistanceTo(p2));
CvPoint2D32f newCenter = (CvPoint2D32f)p0 + edge1 * (desiredWidth / edge1Length) + edge2 * (desiredHeight / edge2Length);
CvBox2D smallEllipse = new CvBox2D(newCenter, new CvSize2D32f((float)desiredWidth, (float)desiredHeight), ellipse.Angle);
return smallEllipse;
}
/// <summary> assure that the width of the elipse is the major axis, and the height is the minor axis.
/// Swap widht/height and rotate by 90° otherwise </summary>
private static CvBox2D NormalizeEllipse(CvBox2D ellipse)
{
if (ellipse.Size.Width < ellipse.Size.Height)
{
ellipse = new CvBox2D(ellipse.Center, new CvSize2D32f(ellipse.Size.Height, ellipse.Size.Width), (ellipse.Angle + 90 + 360) % 360);
}
return ellipse;
}
/// <summary> greater than 1 for points outside ellipse, smaller than 1 for points inside ellipse </summary>
private static double ellipseMetric(CvPoint p, CvBox2D ellipse)
{
double theta = ellipse.Angle * Math.PI / 180;
double u = Math.Cos(theta) * (p.X - ellipse.Center.X) + Math.Sin(theta) * (p.Y - ellipse.Center.Y);
double v = -Math.Sin(theta) * (p.X - ellipse.Center.X) + Math.Cos(theta) * (p.Y - ellipse.Center.Y);
return u * u / (ellipse.Size.Width * ellipse.Size.Width / 4) + v * v / (ellipse.Size.Height * ellipse.Size.Height / 4);
}
/// <summary> Is the point on the ellipseBorder, within a certain tolerance </summary>
private static bool isOnEllipse(CvPoint p, CvBox2D ellipse, double toleranceInner, double toleranceOuter)
{
double theta = ellipse.Angle * Math.PI / 180;
double u = Math.Cos(theta) * (p.X - ellipse.Center.X) + Math.Sin(theta) * (p.Y - ellipse.Center.Y);
double v = -Math.Sin(theta) * (p.X - ellipse.Center.X) + Math.Cos(theta) * (p.Y - ellipse.Center.Y);
double innerEllipseMajor = (ellipse.Size.Width - toleranceInner) / 2;
double innerEllipseMinor = (ellipse.Size.Height - toleranceInner) / 2;
double outerEllipseMajor = (ellipse.Size.Width + toleranceOuter) / 2;
double outerEllipseMinor = (ellipse.Size.Height + toleranceOuter) / 2;
double inside = u * u / (innerEllipseMajor * innerEllipseMajor) + v * v / (innerEllipseMinor * innerEllipseMinor);
double outside = u * u / (outerEllipseMajor * outerEllipseMajor) + v * v / (outerEllipseMinor * outerEllipseMinor);
return inside >= 1 && outside <= 1;
}
/// <summary> count the number of foreground pixels for this grain </summary>
public int CountPixel(CvMat img)
{
// todo: this is an incredibly inefficient way to count, allocating a new image with the size of the input each time
using (CvMat mask = new CvMat(img.Rows, img.Cols, MatrixType.U8C1))
{
mask.SetZero();
mask.FillPoly(new CvPoint[][] { this.EdgePoints.Select(p => p.Point).ToArray() }, CvColor.White);
mask.And(img, mask);
this.NumPixel = mask.CountNonZero();
}
return this.NumPixel;
}
/// <summary> draw the recognized shape of the grain </summary>
public void Draw(CvMat img, CvColor color)
{
img.FillPoly(new CvPoint[][] { this.EdgePoints.Select(p => p.Point).ToArray() }, color);
}
/// <summary> draw the contours of the grain </summary>
public void DrawContour(CvMat img, CvColor color)
{
img.DrawPolyLine(new CvPoint[][] { this.EdgePoints.Select(p => p.Point).ToArray() }, true, color);
}
/// <summary> draw the best-fit ellipse of the grain </summary>
public void DrawEllipse(CvMat img, CvColor color)
{
img.DrawEllipse(this.Position, new CvSize2D32f(this.MajorRadius, this.MinorRadius), this.Angle, 0, 360, color, 1);
}
/// <summary> print the grain index and the number of pixels divided by the average grain size</summary>
public void DrawText(double averageGrainSize, CvMat img, CvColor color)
{
img.PutText(String.Format("{0}|{1:0.0}", this.Index, this.NumPixel / averageGrainSize), this.Position + new CvPoint2D32f(-5, 10), font01, color);
}
}
Estou um pouco envergonhado com esta solução porque a) não tenho certeza se está dentro do espírito desse desafio eb) é muito grande para uma resposta do codegolf e não tem a elegância das outras soluções.
Por outro lado, estou muito feliz com o progresso que obtive na rotulagem dos grãos, não apenas contando-os, então é isso.
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