[英]Create java.awt.geom.Area from points
我試圖創建一個java.awt.geom.Area(或使用Shape接口的任何對象)來描述一組創建復雜形狀的點。 這是一個例子:
我正在嘗試創建一個Area對象(或許多Area對象)來描述黃色區域。 我有一個簡單的方法來獲取黃色像素的坐標,但是我不知道如何創建一個包含所有黃色點的Area對象(或多個Area對象)。
這個stackoverflow問題似乎非常相關( 從邊界點創建封閉的多邊形 ),但是正在使用Matlab。 我認為有人在這里問了一個非常類似的問題( 將列表java.awt.geom.Point2D轉換為java.awt.geom.Area ),但是答案中提供的鏈接已失效。
例如
import java.awt.*;
import java.awt.image.BufferedImage;
import java.awt.geom.Area;
import javax.imageio.ImageIO;
import java.io.File;
import java.net.URL;
import java.util.Date;
import javax.swing.*;
/* See also http://stackoverflow.com/q/7052422/418556 */
class ImageOutline {
public static Area getOutline(
BufferedImage image, Color color, boolean include, int tolerance) {
Area area = new Area();
for (int x=0; x<image.getWidth(); x++) {
for (int y=0; y<image.getHeight(); y++) {
Color pixel = new Color(image.getRGB(x,y));
if (include) {
if (isIncluded(color, pixel, tolerance)) {
Rectangle r = new Rectangle(x,y,1,1);
area.add(new Area(r));
}
} else {
if (!isIncluded(color, pixel, tolerance)) {
Rectangle r = new Rectangle(x,y,1,1);
area.add(new Area(r));
}
}
}
}
return area;
}
public static boolean isIncluded(
Color target, Color pixel, int tolerance) {
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 static BufferedImage drawOutline(int w, int h, Area area) {
final BufferedImage result = new BufferedImage(
w,
h,
BufferedImage.TYPE_INT_RGB);
Graphics2D g = result.createGraphics();
g.setColor(Color.white);
g.fillRect(0,0,w,h);
g.setClip(area);
g.setColor(Color.red);
g.fillRect(0,0,w,h);
g.setClip(null);
g.setStroke(new BasicStroke(1));
g.setColor(Color.blue);
g.draw(area);
return result;
}
public static BufferedImage createAndWrite(
BufferedImage image,
Color color,
boolean include,
int tolerance,
String name)
throws Exception {
int w = image.getWidth();
int h = image.getHeight();
System.out.println("Get Area: " + new Date() + " - " + name);
Area area = getOutline(image, color, include, tolerance);
System.out.println("Got Area: " + new Date() + " - " + name);
final BufferedImage result = drawOutline(w,h,area);
displayAndWriteImage(result, name);
return result;
}
public static void displayAndWriteImage(
BufferedImage image, String fileName) throws Exception {
ImageIO.write(image, "png", new File(fileName));
JOptionPane.showMessageDialog(null, new JLabel(new ImageIcon(image)));
}
public static void main(String[] args) throws Exception {
URL url = new URL("http://i.stack.imgur.com/aGBuT.png");
final BufferedImage outline = ImageIO.read(url);
displayAndWriteImage(outline, "motorcycle-01.png");
createAndWrite(
outline, Color.white, false, 60, "YellowBlobOutline.png");
}
}
我將創建一個GeneralPath或Path2D ,它們都實現Shape
。 本教程說明了如何使用GeneralPath
,它與Path2D
非常相似。 然后可以使用Shape
來創建Area
。
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.