Initial data commit

Task/Median-filter/Java/median-filter.java

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+import java.awt.Color;
+import java.awt.Graphics;
+import java.awt.Image;
+import java.awt.image.BufferedImage;
+import java.awt.image.RenderedImage;
+import java.io.File;
+import java.io.IOException;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.List;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import javax.imageio.ImageIO;
+
+public final class MedianFilter {
+
+	public static void main(String[] aArgs) {
+		try {
+			BufferedImage image = ImageIO.read( new File("beforeFilter.png") );
+			BasicBitmapStorage bitmap = new BasicBitmapStorage(image.getWidth(null), image.getHeight(null));
+		
+	        for ( int y = 0; y < image.getHeight(null); y++ ) {
+	            for ( int x = 0; x < image.getWidth(null); x++ ) {
+	                bitmap.setPixel(x, y, new Color(image.getRGB(x, y), true));
+	            }
+	        }
+	
+	        bitmap.medianFilter(3, 3);
+	        File fileAfterFilter = new File("afterFilter.png");
+	        ImageIO.write((RenderedImage) bitmap.getImage(), "png", fileAfterFilter);
+		} catch (IOException ioe) {
+			ioe.printStackTrace();
+		}
+	}	
+	
+}
+
+final class BasicBitmapStorage {
+
+	public BasicBitmapStorage(int aWidth, int aHeight) {
+        image = new BufferedImage(aWidth, aHeight, BufferedImage.TYPE_INT_RGB);
+    }
+
+    public void fill(Color aColor) {
+        Graphics graphics = image.getGraphics();
+        graphics.setColor(aColor);
+        graphics.fillRect(0, 0, image.getWidth(), image.getHeight());
+    }
+
+    public Color getPixel(int aX, int aY) {
+        return new Color(image.getRGB(aX, aY));
+    }
+
+    public void setPixel(int aX, int aY, Color aColor) {
+        image.setRGB(aX, aY, aColor.getRGB());
+    }
+
+    public Image getImage() {
+    	return image;
+    }
+
+    public void medianFilter(int aWindowWidth, int aWindowHeight) {
+    	List<Color> window = Stream.generate( () -> Color.BLACK )
+    		.limit(aWindowWidth * aWindowHeight).collect(Collectors.toList());	
+        final int edgeX = aWindowWidth / 2;
+        final int edgeY = aWindowHeight / 2;
+        Comparator<Color> luminanceComparator = (one, two) -> Double.compare(luminance(one), luminance(two));
+
+        for ( int x = edgeX; x < image.getWidth() - edgeX; x++ ) {
+            for ( int y = edgeY; y < image.getHeight() - edgeY; y++ ) {
+                int i = 0;
+                for ( int fx = 0; fx < aWindowWidth; fx++ ) {
+                    for ( int fy = 0; fy < aWindowHeight; fy++ ) {
+                        window.set(i, getPixel(x + fx - edgeX, y + fy - edgeY));
+                        i += 1;
+                    }
+                }
+
+                Collections.sort(window, luminanceComparator);
+                setPixel(x, y, window.get(aWindowWidth * aWindowHeight / 2));
+            }
+        }
+    }
+
+    private double luminance(Color aColor) {
+    	return 0.2126 * aColor.getRed() + 0.7152 * aColor.getGreen() + 0.0722 * aColor.getBlue();
+    }
+
+    private final BufferedImage image;
+
+}