前几天，我参加了Image/Graphic into a Shape线程，并尝试通过向Rectangle迭代添加Area来获取图像轮廓。那太慢了。
该示例改为构建GeneralPath并从GP创建Area。快多了。
左上方的图像是“源图像”。右边的两个是处理轮廓的各个阶段。它们两个都在圆周围和三角形的斜边上有锯齿状的边缘。
我想获得一种形状，该形状已消除或减小了锯齿状。
在ASCII艺术中。
情况1:
1234
1 **
2 **
3 ***
4 ***
5 ****
6 ****
情况2:
1234
1 ****
2 ****
3 **
4 **
5 ****
6 ****
假设我们的路径具有所示的形状和列出的点，我想删除第一组的“内角”点，同时保留“成对”的内角(咬住图像) 2号
PathIterator并构建一个新的GeneralPath来删除单数内角-如果只有我能弄清楚如何识别它们的话!)。 这是要使用的代码:
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.awt.geom.*;
import javax.swing.*;
import javax.swing.border.*;
import javax.swing.event.*;
/* Gain the outline of an image for further processing. */
class ImageOutline {
private BufferedImage image;
private TwoToneImageFilter twoToneFilter;
private BufferedImage imageTwoTone;
private JLabel labelTwoTone;
private BufferedImage imageOutline;
private Area areaOutline = null;
private JLabel labelOutline;
private JLabel targetColor;
private JSlider tolerance;
private JProgressBar progress;
private SwingWorker sw;
public ImageOutline(BufferedImage image) {
this.image = image;
imageTwoTone = new BufferedImage(
image.getWidth(),
image.getHeight(),
BufferedImage.TYPE_INT_RGB);
}
public void drawOutline() {
if (areaOutline!=null) {
Graphics2D g = imageOutline.createGraphics();
g.setColor(Color.WHITE);
g.fillRect(0,0,imageOutline.getWidth(),imageOutline.getHeight());
g.setColor(Color.RED);
g.setClip(areaOutline);
g.fillRect(0,0,imageOutline.getWidth(),imageOutline.getHeight());
g.setColor(Color.BLACK);
g.setClip(null);
g.draw(areaOutline);
g.dispose();
}
}
public Area getOutline(Color target, BufferedImage bi) {
// construct the GeneralPath
GeneralPath gp = new GeneralPath();
boolean cont = false;
int targetRGB = target.getRGB();
for (int xx=0; xx<bi.getWidth(); xx++) {
for (int yy=0; yy<bi.getHeight(); yy++) {
if (bi.getRGB(xx,yy)==targetRGB) {
if (cont) {
gp.lineTo(xx,yy);
gp.lineTo(xx,yy+1);
gp.lineTo(xx+1,yy+1);
gp.lineTo(xx+1,yy);
gp.lineTo(xx,yy);
} else {
gp.moveTo(xx,yy);
}
cont = true;
} else {
cont = false;
}
}
cont = false;
}
gp.closePath();
// construct the Area from the GP & return it
return new Area(gp);
}
public JPanel getGui() {
JPanel images = new JPanel(new GridLayout(2,2,2,2));
JPanel gui = new JPanel(new BorderLayout(3,3));
JPanel originalImage = new JPanel(new BorderLayout(2,2));
final JLabel originalLabel = new JLabel(new ImageIcon(image));
targetColor = new JLabel("Target Color");
targetColor.setForeground(Color.RED);
targetColor.setBackground(Color.WHITE);
targetColor.setBorder(new LineBorder(Color.BLACK));
targetColor.setOpaque(true);
JPanel controls = new JPanel(new BorderLayout());
controls.add(targetColor, BorderLayout.WEST);
originalLabel.addMouseListener( new MouseAdapter() {
@Override
public void mouseEntered(MouseEvent me) {
originalLabel.setCursor(
Cursor.getPredefinedCursor(Cursor.CROSSHAIR_CURSOR));
}
@Override
public void mouseExited(MouseEvent me) {
originalLabel.setCursor(Cursor.getDefaultCursor());
}
@Override
public void mouseClicked(MouseEvent me) {
int x = me.getX();
int y = me.getY();
Color c = new Color( image.getRGB(x,y) );
targetColor.setBackground( c );
updateImages();
}
});
originalImage.add(originalLabel);
tolerance = new JSlider(
JSlider.HORIZONTAL,
0,
255,
104
);
tolerance.addChangeListener( new ChangeListener() {
public void stateChanged(ChangeEvent ce) {
updateImages();
}
});
controls.add(tolerance, BorderLayout.CENTER);
gui.add(controls,BorderLayout.NORTH);
images.add(originalImage);
labelTwoTone = new JLabel(new ImageIcon(imageTwoTone));
images.add(labelTwoTone);
images.add(new JLabel("Smoothed Outline"));
imageOutline = new BufferedImage(
image.getWidth(),
image.getHeight(),
BufferedImage.TYPE_INT_RGB
);
labelOutline = new JLabel(new ImageIcon(imageOutline));
images.add(labelOutline);
updateImages();
progress = new JProgressBar();
gui.add(images, BorderLayout.CENTER);
gui.add(progress, BorderLayout.SOUTH);
return gui;
}
private void updateImages() {
if (sw!=null) {
sw.cancel(true);
}
sw = new SwingWorker() {
@Override
public String doInBackground() {
progress.setIndeterminate(true);
adjustTwoToneImage();
labelTwoTone.repaint();
areaOutline = getOutline(Color.BLACK, imageTwoTone);
drawOutline();
return "";
}
@Override
protected void done() {
labelOutline.repaint();
progress.setIndeterminate(false);
}
};
sw.execute();
}
public void adjustTwoToneImage() {
twoToneFilter = new TwoToneImageFilter(
targetColor.getBackground(),
tolerance.getValue());
Graphics2D g = imageTwoTone.createGraphics();
g.drawImage(image, twoToneFilter, 0, 0);
g.dispose();
}
public static void main(String[] args) throws Exception {
int size = 150;
final BufferedImage outline =
new BufferedImage(size,size,BufferedImage.TYPE_INT_RGB);
Graphics2D g = outline.createGraphics();
g.setColor(Color.WHITE);
g.fillRect(0,0,size,size);
g.setRenderingHint(
RenderingHints.KEY_DITHERING,
RenderingHints.VALUE_DITHER_ENABLE);
g.setRenderingHint(
RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
Polygon p = new Polygon();
p.addPoint(size/2, size/10);
p.addPoint(size-10, size-10);
p.addPoint(10, size-10);
Area a = new Area(p);
Rectangle r = new Rectangle(size/4, 8*size/10, size/2, 2*size/10);
a.subtract(new Area(r));
int radius = size/10;
Ellipse2D.Double c = new Ellipse2D.Double(
(size/2)-radius,
(size/2)-radius,
2*radius,
2*radius
);
a.subtract(new Area(c));
g.setColor(Color.BLACK);
g.fill(a);
ImageOutline io = new ImageOutline(outline);
JFrame f = new JFrame("Image Outline");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.add(io.getGui());
f.pack();
f.setResizable(false);
f.setLocationByPlatform(true);
f.setVisible(true);
}
}
class TwoToneImageFilter implements BufferedImageOp {
Color target;
int tolerance;
TwoToneImageFilter(Color target, int tolerance) {
this.target = target;
this.tolerance = tolerance;
}
private boolean isIncluded(Color pixel) {
int rT = target.getRed();
int gT = target.getGreen();
int bT = target.getBlue();
int rP = pixel.getRed();
int gP = pixel.getGreen();
int bP = pixel.getBlue();
return(
(rP-tolerance<=rT) && (rT<=rP+tolerance) &&
(gP-tolerance<=gT) && (gT<=gP+tolerance) &&
(bP-tolerance<=bT) && (bT<=bP+tolerance) );
}
public BufferedImage createCompatibleDestImage(
BufferedImage src,
ColorModel destCM) {
BufferedImage bi = new BufferedImage(
src.getWidth(),
src.getHeight(),
BufferedImage.TYPE_INT_RGB);
return bi;
}
public BufferedImage filter(
BufferedImage src,
BufferedImage dest) {
if (dest==null) {
dest = createCompatibleDestImage(src, null);
}
for (int x=0; x<src.getWidth(); x++) {
for (int y=0; y<src.getHeight(); y++) {
Color pixel = new Color(src.getRGB(x,y));
Color write = Color.BLACK;
if (isIncluded(pixel)) {
write = Color.WHITE;
}
dest.setRGB(x,y,write.getRGB());
}
}
return dest;
}
public Rectangle2D getBounds2D(BufferedImage src) {
return new Rectangle2D.Double(0, 0, src.getWidth(), src.getHeight());
}
public Point2D getPoint2D(
Point2D srcPt,
Point2D dstPt) {
// no co-ord translation
return srcPt;
}
public RenderingHints getRenderingHints() {
return null;
}
}
最佳答案
这是一个大课题。您可能会发现Depixelizing Pixel Art by Johannes Kopf & Dani Lischinski有用:它是可读的，最新的，包括以前工作的摘要，并详细说明了他们的方法。
另请参见slides covering similar background和video(!)。
关于java - 平滑锯齿状的路径，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/7218309/