需求:
在浏览器中给用户呈现一张图片,用户点击图片中的某些标志物,需要系统给出标志物的信息反馈,达到一个交互的作用。
比如下图中,点击某个封闭区域时候,需要告知用户点击的区域名称及图形形状特性等等。
实现思路模仿 window系统中画图工具的区域填充工具。
当我们给一个封闭区域填充色彩的时候,整个区域都将得到填充相同的颜色,此区域封闭即可,这样我们将一张图片中的不同区域填充不同的色彩,得到如下的图片:
后续只需要通过xy坐标得到颜色,在通过颜色得到对应的图片相关信息即可。应用时候的复杂度为O(1)
实现代码如下:
import javax.imageio.ImageIO;import static org.assertj.core.api.Assertions.useDefaultDateFormatsOnly;import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;public class ImageRGBMatrix {//边界的颜色static final int flagColor = 237;//需要填充的色彩static int setColor = 20+(0xFF << 8);public static void main(String[] args) {try {// 读取图片BufferedImage image = ImageIO.read(new File("C:\\Users\\hxd\\Desktop\\pdy.png"));int width = image.getWidth();int height = image.getHeight();初始化特征矩阵//int[][] characteristicMatrix = new int[width][height];// 遍历图片的每个像素for (int x = 0; x < width; x++) {for (int y = 0; y < height; y++) {// 获取(x, y)位置的像素int pixel = image.getRGB(x, y);// 获取RGB分量short red = (short) ((pixel >> 16) & 0xFF);
// short green = (short) ((pixel >> 8) & 0xFF);
// short blue = (short) (pixel & 0xFF);characteristicMatrix[x][y] = red;}}///初始化特征矩阵完成////基于点进行矩阵区域填充/List<Point> ps = new ArrayList<>();ps.add(new Point(116,140,"1","A",0));ps.add(new Point(427,116,"2","B",0));ps.add(new Point(203,426,"3","C",0));ps.add(new Point(661,382,"4","D",0));ps.add(new Point(543,609,"5","E",0));Map<Integer,Point> color2Points = new HashMap<>(); for (Point p : ps) {int my = p.getY();int mx = p.getX();setColor += 40;p.setColor(setColor);color2Points.put(setColor, p);//初始上for (int y = my; y > -1 && characteristicMatrix[mx][y] !=flagColor; y--) {characteristicMatrix[mx][y] = setColor;}//初始下for (int y = my+1; y < height && characteristicMatrix[mx][y] !=flagColor; y++) {characteristicMatrix[mx][y] = setColor;}//记录是否有新增加的点boolean isAdd = true;while(isAdd) {//一旦没有扩充新鲜点,则退出//横向扩充isAdd = leftRigthScan(width, height, characteristicMatrix);if(isAdd) {//轴向扩充isAdd = upDownScan(width, height, characteristicMatrix);}}}///基于点进行矩阵区域填充完成////开始实在使用,找到具体的点在哪个区域/ List<Point> pp = new ArrayList<>();pp.add(new Point(116,140));pp.add(new Point(116,145));pp.add(new Point(596,358));for (Point p : pp) {int color = characteristicMatrix[p.getX()][p.getY()];System.out.println(color2Points.get(color));}///开始实在使用,找到具体的点在哪个区域完成////可视化输出,仅仅是让给人看看填充是否正确,对实际使用没有作用/BufferedImage image1 = new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);for (int x = 0; x < width; x++) {for (int y = 0; y < height; y++) {image1.setRGB(x,y,characteristicMatrix[x][y]);}}ImageIO.write(image1, "png", new File("d:\\pdypdypdy.png"));///可视化输出,仅仅是让给人看看填充是否正确,对实际使用没有作用/} catch (IOException e) {e.printStackTrace();}}/*** 纵向扫描* 从左到右一列一列的扫描:* 从上到下扫描y列: (y在变化)* 1、如果是非着色的点,则继续下移。如果是着色点,执行2、3两步骤。如果超出数组边界则开始下一列* 2、基于此着色点向上侧扩张,直到上侧点是边界点或者下标超出数组下界0;* 3、基于此着色点向下侧扩张,直到下侧点是边界点或者下标超出数组上界height;更新扫描点为当前最下侧扩张点 继续第1步执行。;* * * @param width* @param height* @param characteristicMatrix* @return*/private static boolean upDownScan(int width, int height, int[][] characteristicMatrix) {boolean isAdd = false;//看横向的线for (int x = 0; x < width; x++) {int y = 0;while(y < height) {for (; y < height; y++) {if(characteristicMatrix[x][y] == setColor) {break ;}}if(y < height) {//此列有//处理上边for (int uy = y-1; uy > -1 && characteristicMatrix[x][uy] !=flagColor; uy--) {if(characteristicMatrix[x][uy] != setColor) {characteristicMatrix[x][uy] = setColor;isAdd = true;}}//处理下边for (y = y+1; y < height && characteristicMatrix[x][y] !=flagColor; y++) {if(characteristicMatrix[x][y] != setColor) {characteristicMatrix[x][y] = setColor;isAdd = true;}}}}}return isAdd;}//左右横向扫描/*** 左右横向扫描* 从上到下一行一行的开始扫描扩张。* 从左到右扫描x行:* 1、如果是非着色的点,则继续右移。如果是角色点,执行2、3两步骤。如果超出数组边界则开始下一行* 2、基于此着色点向左侧扩张,直到左侧点是边界点或者下标超出数组下界0;* 3、基于此着色点向右侧扩张,直到右侧点是边界点或者下标超出数组上界width;更新扫描点为当前最右侧扩张点 继续第1步执行。;* * @param width* @param height* @param characteristicMatrix* @return*/protected static boolean leftRigthScan(int width, int height, int[][] characteristicMatrix) {boolean isAdd = false;for (int y = 0; y < height; y++) {int x = 0;while(x < width) {for (; x < width; x++) {if(characteristicMatrix[x][y] == setColor) {break ;}}if(x < width) {//此行有//处理左边for (int lx = x-1; lx > -1 && characteristicMatrix[lx][y] !=flagColor; lx--) {if(characteristicMatrix[lx][y] != setColor) {characteristicMatrix[lx][y] = setColor;isAdd = true;}}//处理右边for (x = x+1; x < width && characteristicMatrix[x][y] !=flagColor; x++) {if(characteristicMatrix[x][y] != setColor) {characteristicMatrix[x][y] = setColor;isAdd = true;}}}}}return isAdd;}
}