javaimportants/test03.java

import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.io.*;

public class test03 {
    public static void main(String[] args) {
        jpgTostring("D:\\Java库\\福禄娃.jpg");
    }
    public static void jpgTostring(String imagePath) {
        String base = "MNHQ&OC?7>!;:-. ";
        try {
            PrintWriter out = new PrintWriter("D:\\Java库\\福禄娃.txt");
            BufferedImage image = ImageIO.read(new File(imagePath)); //读取图片
            //输出到指定文件中
            for (int y = 0; y < image.getHeight(); y+=2) {
                for (int x = 0; x < image.getWidth(); x++) {
                    int pixel = image.getRGB(x, y);
                    int r = (pixel & 0xff0000) >> 16, g = (pixel & 0xff00) >> 8, b = pixel & 0xff;//分别获取 r、g、b 的值

                    float gray = 0.3f * r + 0.59f * g + 0.11f * b;//灰度计算公式

                    int index = Math.round(gray * (base.length() + 1) / 255);
                    String s = index >= base.length() ? " " : String.valueOf(base.charAt(index));
                    out.print(s);
                }
                out.println();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}