Example Morphological Thinning

• 

  Input image of a finger print

• 

  Binary image

• 

  Thinned image

Example of how to thin a binary image. The thinned image (or skeleton) is a common preprocessing step in shape analysis.

Example Code:

• ExampleMorphologicalThinning.java

Concepts:

• Binary Processing
• Shapes
• Thinning

Example Code

/**
 * Simple example showing you how to thin a binary image.  This is also known as skeletonalization.  Thinning
 * discards most of objects foreground (value one) pixels are leaves behind a "skinny" object which still
 * mostly describes the original objects shape.
 *
 * @author Peter Abeles
 */
public class ExampleMorphologicalThinning {
	public static void main(String[] args) {
		// load and convert the image into a usable format
		BufferedImage image = UtilImageIO.loadImage("../data/applet/standard/fingerprint.jpg");

		// convert into a usable format
		ImageFloat32 input = ConvertBufferedImage.convertFromSingle(image, null, ImageFloat32.class);
		ImageUInt8 binary = new ImageUInt8(input.width,input.height);

		// Adaptive threshold to better handle changes in local image intensity
		GThresholdImageOps.adaptiveGaussian(input,binary,10,0,true,null,null);

		// Tell it to thin the image until there are no more changes
		ImageUInt8 thinned = BinaryImageOps.thin(binary, -1, null);

		// display the results
		BufferedImage visualBinary = VisualizeBinaryData.renderBinary(binary, false, null);
		BufferedImage visualThinned = VisualizeBinaryData.renderBinary(thinned, false, null);

		ListDisplayPanel panel = new ListDisplayPanel();
		panel.addImage(visualThinned, "Thinned");
		panel.addImage(visualBinary, "Binary");
		panel.addImage(image, "Original");

		ShowImages.showWindow(panel,"Thinned/Skeletonalized Image", true);
	}
}