/* * ImageMaskFilter.java * Code: Jan Humble * */ import java.awt.event.*; import java.applet.*; import java.awt.*; import java.awt.image.*; import java.util.StringTokenizer; import java.net.*; public class ImageMaskFilter extends Applet { int mask[][]; // current mask to apply int maskSizeX = 5; // mask size int maskSizeY = 5; // mask size double weight = 1; // weight for the mask values InputPanel inputPanel; TextArea messageArea; ImageCanvas imageCanvas; int imageCanvasdX = 350; int imageCanvasdY = 350; String imageFile = "figures.jpg"; // file name for image file Image imgOriginal; // Original image Image img; // Image to paint int[] imagePixels; // Pixel values for image int imagePixelsWidth, imagePixelsHeight; public void init(){ // set the layout setLayout(new BorderLayout()); Label title = new Label("Image Mask Filtering", Label.CENTER); title.setFont(new Font("Helvetica", Font.BOLD, 14)); title.setBackground(Color.white); inputPanel = new InputPanel(this); inputPanel.setSize(180, 200); imageCanvas = new ImageCanvas(this); add("North", title); add("West", imageCanvas); add("Center", inputPanel); messageArea = new TextArea("", 2, 1); messageArea.setEditable(false); messageArea.setBackground(Color.white); add("South", messageArea); // load default file loadImage(imageFile, getCodeBase()); // create default mask & set values createMask(); inputPanel.maskPanel.setValues(mask); imageCanvas.repaint(); } public void createMask() { mask = new int[maskSizeY][maskSizeX]; } // Separate colors and alpha value from given pixel-int public int[] separateColors(int argb) { int result[] = { (argb >> 24) & 0xff, (argb >> 16) & 0xff, (argb >> 8) & 0xff, (argb ) & 0xff }; return result; } // Perform convolution between mask and // function of equal size as mask public int convolute(int[][] pixels, int[][] mask, double weight) { double result = 0; double norm = 1; for (int j = 0; j < maskSizeY; j++) for (int i = 0; i < maskSizeX; i++) { result += weight*pixels[j][i]*mask[j][i]; } if (result > 255) result = 255; else if (result < 0) result = -result; return (int) result; } // Apply filter public void applyFilter() { messageArea.setText("Calculating ..."); int[] filtImage = new int[(imagePixelsWidth - 4)*(imagePixelsHeight - 4)]; int p = 0; for (int y = 2; y < imagePixelsHeight - 2; y++) for (int x = 2; x < imagePixelsWidth -2; x++) { // get Pixels needed to calculate mask int [][] alphaPixels = new int[maskSizeX][maskSizeY]; int [][] redPixels = new int[maskSizeX][maskSizeY]; int [][] greenPixels = new int[maskSizeX][maskSizeY]; int [][] bluePixels = new int[maskSizeX][maskSizeY]; for (int j = 0; j < maskSizeY; j++) for (int i = 0; i < maskSizeX; i++) { // NOTE: Take into account only 5X5 mask int[] argb = separateColors(imagePixels [(x - 2 + i)+(y - 2 + j)* imagePixelsWidth]); // Works with all colors // Calculations can be improved for // greyscale images (only 1 calc) alphaPixels[j][i] = argb[0]; redPixels[j][i] = argb[1]; greenPixels[j][i] = argb[2]; bluePixels[j][i] = argb[3]; } // for each pixel calculate new value int newalpha = 255; // unchanged int newred = convolute(redPixels, mask, weight); int newgreen = convolute(greenPixels, mask, weight); int newblue = convolute(bluePixels, mask, weight); filtImage[p] = (newalpha << 24) | (newred << 16) | (newgreen << 8 ) | newblue; p++; } // create new image to display from pixel values img = createImage(new MemoryImageSource(imagePixelsWidth - 4, imagePixelsHeight - 4, filtImage, 0, imagePixelsWidth - 4)); // change filtered image to applet image imagePixelsWidth = imagePixelsWidth - 4; imagePixelsHeight = imagePixelsHeight - 4; imagePixels = filtImage; messageArea.setText("Done Calculating Filter!"); imageCanvas.repaint(); } public void restoreImage() { img = imgOriginal; imageCanvas.repaint(); messageArea.setText("Image restored to original!"); } public boolean loadImage(String file, URL url) { Image grab = getImage(url, file); // Will only grab 100x100 pixels from Image // Otherwise calculations too slow (?) int w = 100; int h = 100; imagePixelsWidth = w; imagePixelsHeight = h; imagePixels = new int[w * h]; PixelGrabber pg = new PixelGrabber(grab, 0, 0, w-1, h-1, imagePixels, 0, w); try { pg.grabPixels(); } catch (InterruptedException e) { messageArea.setText("Interrupted waiting for pixels!"); return false; } if ((pg.getStatus() & ImageObserver.ABORT) != 0) { messageArea.setText("Image fetch aborted or errored"); return false; } imgOriginal = createImage(new MemoryImageSource(w, h, imagePixels, 0, w)); img = createImage(new MemoryImageSource(w, h, imagePixels, 0, w)); imageCanvas.repaint(); messageArea.setText("Image file: " + file + " loaded!"); imageFile = file; return true; } public boolean loadExternalImage(String imageURL) { URL url; String filename; String urlString = ""; StringTokenizer st = new StringTokenizer(imageURL, "/"); int nrOfTokens = st.countTokens(); for (int i = 1; i < nrOfTokens; i++) { urlString += (st.nextToken() + "/"); } urlString.trim(); filename = st.nextToken(); if (urlString.length() == 0) { url = getCodeBase(); } else { urlString = "http://" + urlString; messageArea.setText("locating URL: " + urlString + " File: " + filename); try { url = new URL(urlString); } catch (MalformedURLException mue) { messageArea.setText("Failed locating URL: " + urlString + " File: " + filename); return false; } } return loadImage(filename, url); } } class ImageCanvas extends Canvas { ImageMaskFilter applet; int dX, dY; ImageCanvas(ImageMaskFilter applet) { this.applet = applet; this.setSize(applet.imageCanvasdX, applet.imageCanvasdY); this.dX = getSize().width; this.dY = getSize().height; setBackground(Color.white); } public void paint(Graphics g) { // Clear screen g.setColor(Color.white); g.fillRect(0, 0, dX, dY); g.drawImage(applet.img, 0, 0, dX, dY, this); } } class InputPanel extends Panel implements ActionListener, ItemListener { ImageMaskFilter applet; MaskPanel maskPanel; Button applyButton, resetButton, undoButton, loadButton; TextField weightField, urlField; InputPanel(ImageMaskFilter applet) { this.applet = applet; this.setBackground(Color.white); maskPanel = new MaskPanel(5, 5); applyButton = new Button("Apply"); resetButton = new Button("Reset"); loadButton = new Button("Load Image in Location:"); weightField = new TextField("1", 4); urlField = new TextField(applet.imageFile, 15); applyButton.addActionListener(this); resetButton.addActionListener(this); loadButton.addActionListener(this); add(applyButton); add(resetButton); add(new Label("Weight:")); add(weightField); add(new Label("Mask (5 X 5):")); add(maskPanel); Choice c = new Choice (); c.addItem("Identity"); c.addItem("1st Der"); c.addItem("1st Der 0 deg"); c.addItem("1st Der 90 deg"); c.addItem("2nd Der 0 deg"); c.addItem("2nd Der 90 deg"); c.addItem("3rd Der 0 deg"); c.addItem("3rd Der 90 deg"); c.addItem("Smoothing"); c.addItemListener(this); add( c ); add(new Label("Image:")); Choice ic = new Choice (); ic.addItem("figures.jpg"); ic.addItem("clarkSmall.jpg"); ic.addItemListener(this); add( ic ); add(loadButton); add(urlField); update(); } public void readValues() { applet.weight = Double.valueOf(weightField.getText()).doubleValue(); maskPanel.readValues(applet.mask); } // Get the choice item events here public void itemStateChanged(ItemEvent e) { String command = e.getItem().toString(); if (command.equals("Identity") ) { maskPanel.setValues(MaskLib.identityMask); weightField.setText(Double.toString(MaskLib.identityWeight)); } else if (command.equals("1st Der") ) { maskPanel.setValues(MaskLib.firstDerMask); weightField.setText(Double.toString(MaskLib.firstDerWeight)); } else if (command.equals("1st Der 0 deg")) { maskPanel.setValues(MaskLib.firstDer0Mask); weightField.setText(Double.toString(MaskLib.firstDer0Weight)); } else if (command.equals("1st Der 90 deg")) { maskPanel.setValues(MaskLib.firstDer90Mask); weightField.setText(Double.toString(MaskLib.firstDer90Weight)); } else if (command.equals("2nd Der 0 deg")) { maskPanel.setValues(MaskLib.secondDer0Mask); weightField.setText(Double.toString(MaskLib.secondDer0Weight)); } else if (command.equals("2nd Der 90 deg")) { maskPanel.setValues(MaskLib.secondDer90Mask); weightField.setText(Double.toString(MaskLib.secondDer90Weight)); } else if (command.equals("3rd Der 0 deg")) { maskPanel.setValues(MaskLib.thirdDer0Mask); weightField.setText(Double.toString(MaskLib.thirdDer0Weight)); } else if (command.equals("3rd Der 90 deg")) { maskPanel.setValues(MaskLib.thirdDer90Mask); weightField.setText(Double.toString(MaskLib.thirdDer90Weight)); } else if (command.equals("Smoothing")) { maskPanel.setValues(MaskLib.smoothMask); weightField.setText(Double.toString(MaskLib.smoothWeight)); } // Local images to load else if (command.equals("figures.jpg") || command.equals("clarkSmall.jpg")) { applet.loadImage(command, applet.getCodeBase()); } } public void actionPerformed(ActionEvent ev) { if (ev.getActionCommand().equals("Apply")) { readValues(); applyButton.setEnabled(false); applet.applyFilter(); restore(); } else if (ev.getActionCommand().equals("Reset")) { applet.restoreImage(); } else if (ev.getActionCommand().equals("Load Image in Location:")) { applet.loadExternalImage(urlField.getText()); } } public void update() { } public void restore() { applyButton.setEnabled(true); } } class MaskPanel extends Panel { int sizeX, sizeY; TextField fieldArray[][]; MaskPanel(int sizeX, int sizeY) { this.sizeX = sizeX; this.sizeY = sizeY; this.setBackground(Color.white); setLayout(new GridLayout(sizeX, sizeY)); fieldArray = new TextField[sizeY][sizeX]; for (int y = 0; y < sizeY; y++) for (int x = 0; x < sizeX; x++) { fieldArray[y][x] = new TextField("0"); add(fieldArray[y][x]); } } void setValues(int intArray[][]) { for (int y = 0; y < sizeY; y++) for (int x = 0; x < sizeX; x++) fieldArray[y][x].setText(Integer.toString(intArray[y][x])); } void readValues(double doubleArray[][]) { for (int y = 0; y < sizeY; y++) for (int x = 0; x < sizeX; x++) doubleArray[y][x] = Double.valueOf(fieldArray[y][x].getText()).doubleValue(); } void readValues(int intArray[][]) { for (int y = 0; y < sizeY; y++) for (int x = 0; x < sizeX; x++) intArray[y][x] = Integer.valueOf(fieldArray[y][x].getText()).intValue(); } }