public DroidCvPattern(Stream Stream, bool MakeMask)
{
var buffer = new byte[Stream.Length];
using var ms = new MemoryStream(buffer);
Stream.CopyTo(ms);
using var raw = new DisposableMat(new MatOfByte(buffer));
if (MakeMask)
{
using var rgbaMat = new DisposableMat(Imgcodecs.Imdecode(raw.Mat, Imgcodecs.CvLoadImageUnchanged));
Mat = new Mat();
Imgproc.CvtColor(rgbaMat.Mat, Mat, Imgproc.ColorRgba2gray);
Mask = new Mat();
// Extract alpha channel
Core.ExtractChannel(rgbaMat.Mat, Mask, 3);
// Mask containing 0 or 255
Imgproc.Threshold(Mask, Mask, 0, 255, Imgproc.ThreshBinary);
}
else
{
Mat = Imgcodecs.Imdecode(raw.Mat, Imgcodecs.CvLoadImageGrayscale);
}
}
public IEnumerable <Match> FindMatches(IPattern Template, double Similarity)
{
using var result = new DisposableMat();
// max is used for tmccoeff
Imgproc.MatchTemplate(Mat, (Template as DroidCvPattern)?.Mat, result.Mat, Imgproc.TmCcoeffNormed);
Imgproc.Threshold(result.Mat, result.Mat, 0.1, 1, Imgproc.ThreshTozero);
while (true)
{
using var minMaxLocResult = Core.MinMaxLoc(result.Mat);
var score = minMaxLocResult.MaxVal;
if (score >= Similarity)
{
var loc = minMaxLocResult.MaxLoc;
var region = new Region((int)loc.X, (int)loc.Y, Template.Width, Template.Height);
yield return(new Match(region, score));
using var mask = new DisposableMat();
// Flood fill eliminates the problem of nearby points to a high similarity point also having high similarity
const double floodFillDiff = 0.05;
Imgproc.FloodFill(result.Mat, mask.Mat, loc, new Scalar(0),
new Rect(),
new Scalar(floodFillDiff), new Scalar(floodFillDiff),
0);
}
else
{
break;
}
}
}
public bool IsMatch(IPattern Template, double Similarity)
{
using var result = new DisposableMat();
Imgproc.MatchTemplate(Mat, (Template as DroidCvPattern)?.Mat, result.Mat, Imgproc.TmCcoeffNormed);
using var minMaxLocResult = Core.MinMaxLoc(result.Mat);
return(minMaxLocResult.MaxVal >= Similarity);
}
public DroidCvPattern(Stream Stream)
{
var buffer = new byte[Stream.Length];
using var ms = new MemoryStream(buffer);
Stream.CopyTo(ms);
using var raw = new DisposableMat(new MatOfByte(buffer));
Mat = Imgcodecs.Imdecode(raw.Mat, Imgcodecs.CvLoadImageGrayscale);
}
DisposableMat Match(DroidCvPattern Template)
{
var result = new DisposableMat();
if (Template.Mask != null)
{
Imgproc.MatchTemplate(Mat, Template.Mat, result.Mat, Imgproc.TmCcorrNormed, Template.Mask);
}
else
{
Imgproc.MatchTemplate(Mat, Template.Mat, result.Mat, Imgproc.TmCcoeffNormed);
}
return(result);
}