private Rect GetRoi(Mat mat)
{
var boxWidth = mat.Width() - (mat.Width() / 3);
var boxHeight = mat.Height() / 6;
var scanBox = new Size(boxWidth, boxHeight);
var xStartingPoint = mat.Width() / 6;
var yStartingPoint = (mat.Height() / 2) - (mat.Height() / 10);
var scanBoxStartingPoint = new Point(xStartingPoint, yStartingPoint);
return(new Rect(scanBoxStartingPoint, scanBox));
}
private void CreateSrcDstArrays(double maxWidth, double maxHeight, OpenCV.Core.Point pTopLeft, OpenCV.Core.Point pBottomLeft, OpenCV.Core.Point pBottomRight, OpenCV.Core.Point pTopRight, out MatOfPoint2f src, out MatOfPoint2f dst)
{
src = new MatOfPoint2f(new OpenCV.Core.Point[4] {
pBottomLeft, pTopLeft, pTopRight, pBottomRight
});
dst = new MatOfPoint2f(new OpenCV.Core.Point[4]
{
new OpenCV.Core.Point(0, 0),
new OpenCV.Core.Point(maxWidth - 1, 0),
new OpenCV.Core.Point(maxWidth - 1, maxHeight - 1),
new OpenCV.Core.Point(0, maxHeight - 1)
});
}
private void GetImageMaxSize(out double maxWidth, out double maxHeight, out OpenCV.Core.Point pTopLeft, out OpenCV.Core.Point pBottomLeft, out OpenCV.Core.Point pBottomRight, out OpenCV.Core.Point pTopRight)
{
var pointArray = detectedBorder.ToArray();
pTopLeft = new OpenCV.Core.Point(pointArray[0].X, pointArray[0].Y);
pBottomLeft = new OpenCV.Core.Point(pointArray[1].X, pointArray[1].Y);
pBottomRight = new OpenCV.Core.Point(pointArray[2].X, pointArray[2].Y);
pTopRight = new OpenCV.Core.Point(pointArray[3].X, pointArray[3].Y);
var w1 = pTopLeft.X - pBottomRight.X;
var w2 = pTopRight.X - pBottomLeft.X;
var h1 = pTopRight.Y - pTopLeft.Y;
var h2 = pBottomLeft.Y - pBottomRight.Y;
maxWidth = w1 > w2 ? w1 : w2;
maxHeight = h1 > h2 ? h1 : h2;
}
/// <summary>
///
/// </summary>
/// <param name="img"></param>
/// <returns></returns>
public static Bitmap greyImg(Bitmap img, double threshValue1, double blurValue)
{
//Matrix für das Bild
Mat imgMat = new Mat();
//Bild zu Matrix umwandeln
Utils.BitmapToMat(img, imgMat);
//-----------------Bild bearbeiten---------------------
//Variablen
//Size s = new Size(10.0, 10.0);
Size s = new Size(blurValue, blurValue);
OpenCV.Core.Point p = new OpenCV.Core.Point(0, 0);
//TODO Matrix größe beachten?
Bitmap bmp = null;
Mat tmpgrey = new Mat(10, 10, CvType.Cv8uc1, new Scalar(4));
Mat tmpblur = new Mat(10, 10, CvType.Cv8uc1, new Scalar(4));
Mat tmpthresh = new Mat(10, 10, CvType.Cv8uc1, new Scalar(4));
Mat imgresult = new Mat(10, 10, CvType.Cv8uc1, new Scalar(4));
try
{
//Grau
Imgproc.CvtColor(imgMat, tmpgrey, Imgproc.ColorBgr2gray, 4);
//Blur
Imgproc.Blur(tmpgrey, tmpblur, s, p);
//Thresh
//Orginal
//Imgproc.Threshold(tmpblur, tmpthresh, 90, 255, Imgproc.ThreshBinary);
Imgproc.Threshold(tmpblur, tmpthresh, threshValue1, 255, Imgproc.ThreshBinary);
//Kontrast
//tmpthresh.ConvertTo(imgresult, -1, 9.0, 10);
bmp = Bitmap.CreateBitmap(tmpthresh.Cols(), tmpthresh.Rows(), Bitmap.Config.Argb8888);
Utils.MatToBitmap(tmpthresh, bmp);
}
catch (CvException e) { System.Console.WriteLine(e.Message); }
return(bmp);
}
public static async Task <string> detectAndExtractText(Bitmap img)
{
//Matrix für die Bilder
Mat large = new Mat();
Mat small = new Mat();
Mat rgb = new Mat();
//Bild zu Matrix umwandeln
Utils.BitmapToMat(img, large);
// downsample and use it for processing
Imgproc.PyrDown(large, rgb);
//Grey
Imgproc.CvtColor(rgb, small, Imgproc.ColorBgr2gray);
//Gradiant
Mat grad = new Mat();
Size morphsize = new Size(3.0, 3.0);
Mat morphKernel = Imgproc.GetStructuringElement(Imgproc.MorphEllipse, morphsize);
Imgproc.MorphologyEx(small, grad, Imgproc.MorphGradient, morphKernel);
//Binarize
Mat bw = new Mat();
Imgproc.Threshold(grad, bw, 0.0, 255.0, Imgproc.ThreshBinary | Imgproc.ThreshOtsu);
// connect horizontally oriented regions
Mat connected = new Mat();
Size connectsize = new Size(9.0, 1.0);
morphKernel = Imgproc.GetStructuringElement(Imgproc.MorphRect, connectsize);
Imgproc.MorphologyEx(bw, connected, Imgproc.MorphClose, morphKernel);
// find contours
Mat mask = Mat.Zeros(bw.Size(), CvType.Cv8uc1);
JavaList <MatOfPoint> contours = new JavaList <MatOfPoint>();
Mat hierarchy = new Mat();
OpenCV.Core.Point contourPoint = new OpenCV.Core.Point(0, 0);
Imgproc.FindContours(connected, contours, hierarchy, Imgproc.RetrCcomp, Imgproc.ChainApproxSimple, contourPoint);
Scalar zero = new Scalar(0, 0, 0);
Scalar contourscal = new Scalar(255, 255, 255);
Scalar rectScalar = new Scalar(0, 255, 0);
OpenCV.Core.Rect rect;
Mat maskROI;
double r;
double[] contourInfo;
string resulttext = "";
string part;
Bitmap bmpOcr;
Mat croppedPart;
for (int i = 0; i >= 0;)
{
rect = Imgproc.BoundingRect(contours[i]);
maskROI = new Mat(mask, rect);
maskROI.SetTo(zero);
//fill the contour
Imgproc.DrawContours(mask, contours, i, contourscal, Core.Filled);
// ratio of non-zero pixels in the filled region
r = (double)Core.CountNonZero(maskROI) / (rect.Width * rect.Height);
/* assume at least 45% of the area is filled if it contains text */
/* constraints on region size */
/* these two conditions alone are not very robust. better to use something
* like the number of significant peaks in a horizontal projection as a third condition */
if (r > .45 && (rect.Height > 8 && rect.Width > 8))
{
//Imgproc.Rectangle(rgb, rect.Br(), rect.Tl(), rectScalar, 2);
try
{
croppedPart = rgb.Submat(rect);
bmpOcr = Bitmap.CreateBitmap(croppedPart.Width(), croppedPart.Height(), Bitmap.Config.Argb8888);
Utils.MatToBitmap(croppedPart, bmpOcr);
part = await OCR.getText(bmpOcr);
resulttext = resulttext + part;
Console.WriteLine("------------------Durchlauf-------------");
}
catch (Exception e)
{
Android.Util.Log.Debug("Fehler", "cropped part data error " + e.Message);
}
}
//Nächste Element bestimmen
contourInfo = hierarchy.Get(0, i);
i = (int)contourInfo[0];
}
return(resulttext);
}
