Difference between revisions of "Example Image Enhancement"

From BoofCV
Jump to navigationJump to search
m
(Updated for v0.16)
Line 10: Line 10:


Example Code:
Example Code:
* [https://github.com/lessthanoptimal/BoofCV/blob/v0.14/examples/src/boofcv/examples/ExampleImageEnhancement.java ExampleImageEnhancement.java]
* [https://github.com/lessthanoptimal/BoofCV/blob/v0.16/examples/src/boofcv/examples/enhance/ExampleImageEnhancement.java ExampleImageEnhancement.java]


Concepts:
Concepts:
Line 17: Line 17:
Relevant Applets:
Relevant Applets:
* [[Applet Image Enhance| Image Enhancement]]
* [[Applet Image Enhance| Image Enhancement]]


= Example Code =
= Example Code =
Line 35: Line 34:
*/
*/
public static void histogram() {
public static void histogram() {
// BufferedImage buffered = UtilImageIO.loadImage("../data/applet/enhance/dull.jpg");
BufferedImage buffered = UtilImageIO.loadImage("../data/applet/enhance/dark.jpg");
BufferedImage buffered = UtilImageIO.loadImage("../data/applet/enhance/dark.jpg");
ImageUInt8 gray = ConvertBufferedImage.convertFrom(buffered,(ImageUInt8)null);
ImageUInt8 gray = ConvertBufferedImage.convertFrom(buffered,(ImageUInt8)null);
Line 62: Line 62:
*/
*/
public static void sharpen() {
public static void sharpen() {
BufferedImage buffered = UtilImageIO.loadImage("../data/applet/enhance/dull.jpg");
// BufferedImage buffered = UtilImageIO.loadImage("../data/applet/enhance/dull.jpg");
BufferedImage buffered = UtilImageIO.loadImage("../data/applet/enhance/dark.jpg");
ImageUInt8 gray = ConvertBufferedImage.convertFrom(buffered,(ImageUInt8)null);
ImageUInt8 gray = ConvertBufferedImage.convertFrom(buffered,(ImageUInt8)null);
ImageUInt8 adjusted = new ImageUInt8(gray.width, gray.height);
ImageUInt8 adjusted = new ImageUInt8(gray.width, gray.height);

Revision as of 13:55, 25 December 2013

Demonstration of different image enhancement operations. If an image is excessively dark or light the visibility of features can be improved by adjusting its histogram. Another technique makes the edges in an image more pronounced by.

Example Code:

Concepts:

  • Visibility

Relevant Applets:

Example Code

/**
 * Demonstration of various ways an image can be "enhanced".  Image enhancement typically refers to making it easier
 * for people to view the image and pick out its details.
 *
 * @author Peter Abeles
 */
public class ExampleImageEnhancement {

	/**
	 * Histogram adjustment algorithms aim to spread out pixel intensity values uniformly across the allowed range.
	 * This if an image is dark, it will have greater contrast and be brighter.
	 */
	public static void histogram() {
//		BufferedImage buffered = UtilImageIO.loadImage("../data/applet/enhance/dull.jpg");
		BufferedImage buffered = UtilImageIO.loadImage("../data/applet/enhance/dark.jpg");
		ImageUInt8 gray = ConvertBufferedImage.convertFrom(buffered,(ImageUInt8)null);
		ImageUInt8 adjusted = new ImageUInt8(gray.width, gray.height);

		int histogram[] = new int[256];
		int transform[] = new int[256];

		ListDisplayPanel panel = new ListDisplayPanel();

		ImageStatistics.histogram(gray,histogram);
		EnhanceImageOps.equalize(histogram, transform);
		EnhanceImageOps.applyTransform(gray, transform, adjusted);
		panel.addImage(ConvertBufferedImage.convertTo(adjusted,null),"Global");

		EnhanceImageOps.equalizeLocal(gray, 50, adjusted, histogram, transform);
		panel.addImage(ConvertBufferedImage.convertTo(adjusted,null),"Local");

		panel.addImage(ConvertBufferedImage.convertTo(gray,null),"Original");

		panel.setPreferredSize(new Dimension(gray.width,gray.height));
		ShowImages.showWindow(panel,"Histogram");
	}

	/**
	 * When an image is sharpened the intensity of edges are made more extreme while flat regions remain unchanged.
	 */
	public static void sharpen() {
//		BufferedImage buffered = UtilImageIO.loadImage("../data/applet/enhance/dull.jpg");
		BufferedImage buffered = UtilImageIO.loadImage("../data/applet/enhance/dark.jpg");
		ImageUInt8 gray = ConvertBufferedImage.convertFrom(buffered,(ImageUInt8)null);
		ImageUInt8 adjusted = new ImageUInt8(gray.width, gray.height);


		ListDisplayPanel panel = new ListDisplayPanel();

		EnhanceImageOps.sharpen4(gray, adjusted);
		panel.addImage(ConvertBufferedImage.convertTo(adjusted,null),"Sharpen-4");

		EnhanceImageOps.sharpen8(gray, adjusted);
		panel.addImage(ConvertBufferedImage.convertTo(adjusted,null),"Sharpen-8");

		panel.addImage(ConvertBufferedImage.convertTo(gray,null),"Original");

		panel.setPreferredSize(new Dimension(gray.width,gray.height));
		ShowImages.showWindow(panel,"Sharpen");
	}

	public static void main( String args[] )
	{
		histogram();
		sharpen();
	}

}