TIEVisionBlobDetector

Declaration

TIEVisionBlobDetector = interface(TIEVisionBase)

Description

An interface to search for blobs/shapes in an image and return a list of keypoints for detected blobs.


Note: A shortcut method for this available: DetectBlobs

Demo

Demos\IEVision\BlobDetection\BlobDetection.dpr

Example

var
  detector: TIEVisionBlobDetector;
  keyPoints: TIEVisionVectorKeyPoint;
  kp: TIEVisionKeyPoint;
  i: integer;
  x1, y1, x2, y2: double;
begin
  detector := IEVisionLib().createBlobDetector();

  // Setup parameters
  detector.setThreshold( StrToFlt( EditThresholdMin.Text, 50), StrToFlt( EditThresholdMax.Text, 220), StrToFlt( EditThresholdStep.Text, 10 ));
  detector.setMinDistBetweenBlobs( StrToFlt( EditMinBlobDistance.Text, 10 ));
  detector.setFilterByGrayLevel( CheckBoxGrayLevelFilter.Checked, ComboBoxColorFilter.ItemIndex * 255 );
  detector.setFilterByArea( CheckBoxAreaFilter.Checked, StrToFlt( EditMinArea.Text, 25 ), StrToFlt( EditMaxArea.Text, 5000 ));
  detector.setFilterByCircularity( CheckBoxCircularityFilter.Checked, StrToFlt( EditMinCircularity.Text, 0.8 ), StrToFlt(EditMaxCircularity.Text, 3.4e+38 ));
  detector.setFilterByInertia( CheckBoxInertiaFilter.Checked, StrToFlt( EditMinInertia.Text, 0.1), StrToFlt( EditMaxInertia.Text, 3.4e+38 ));
  detector.setFilterByConvexity( CheckBoxConvexityFilter.Checked, StrToFlt( EditMinConvexity.Text, 0.95), StrToFlt( EditMaxConvexity.Text, 3.4e+38 ));

  keyPoints := detector.detect( ImageEnView1.IEBitmap.GetIEVisionImage() );

  lblCount.Caption := 'Count: ' + IntToStr( keyPoints.size() );
  for i := 0 to keyPoints.size() - 1 do
  begin
    kp := keyPoints.getKeyPoint(i);

    // Draw onto bitmap
    with ImageEnView1.IEBitmap.Canvas do
    begin
      Pen.Color := clRed;
      Pen.Width := 4;
      Brush.Style := bsClear;
      x1 := kp.pt.x - kp.size / 2;
      y1 := kp.pt.y - kp.size / 2;
      x2 := kp.pt.x + kp.size / 2;
      y2 := kp.pt.y + kp.size / 2;
      Ellipse( Round(x1), Round(y1), Round(x2), Round(y2));
    end;
  end;

  ImageEnView1.Update();
end;

Methods and Properties

See Also

◼createBlobDetector
◼DrawRects

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