简单图形验证码的识别

核心提示：文章来源：http://zzzhc.spaces.MSN.com/blog/cns!3905D34B10C3C381!129.entry 对于简单的图形验证码(字体规则,没有杂点或杂点容易过滤掉),用模板匹配的方式可以比较容易地识别出来.0.图片黑白化,用1表示有字的像素,0表示无字的像素1.字块分隔,将图片分隔成只包

　　文章来源：
http://zzzhc.spaces.MSN.com/blog/cns!3905D34B10C3C381!129.entry
　　
　　　对于简单的图形验证码(字体规则,没有杂点或杂点容易过滤掉),
用模板匹配的方式可以比较容易地识别出来.

　0.图片黑白化,用1表示有字的像素,0表示无字的像素

　1.字块分隔,将图片分隔成只包含成单字的最小块

　2.生成模板,将字块与字符关联

　3.识别,将新图片分块并与模板匹配

java(jdk1.5)实现:
//先运行TemplateCreator创建模板,再运行Recognize2识别

　　　　　　　　　　 

//图片数据表示,也用来表示字块
package pay365;
import java.awt.image.BufferedImage;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
public class ImageData {
    public int[][] data;
    public int w;
    public int h;
    public char code;
    
    public ImageData() {
    }
    
    public ImageData(BufferedImage bi) {
        this(bi,new WhiteFilter());
    }
    public ImageData(BufferedImage bi,Filter filter) {
        h = bi.getHeight();
        w = bi.getWidth();
        data = new int[h][w];
        for (int i = 0; i < h; i++) {
            for (int j = 0; j < w; j++) {
                int p = bi.getRGB(j, i);
                data[i][j] = p;
            }
        }
        filter.doFilter(data);
    }
    public ImageData[] split() {
        ArrayList list = new ArrayList();
        ImageIterator ite = new ImageIterator(this);
        while (ite.hasNext()) {
            list.add(ite.next());
        }
        return (ImageData[]) list.toArray(new ImageData[0]);
    }
    int skipEmpty(int begin, boolean isX, int value) {
        if (isX) {
            for (int i = begin; i < w; i++) {
                for (int j = 0; j < h; j++) {
                    if (data[j][i] != value) {
                        return i;
                    }
                }
            }
            return -1;
        } else {
            for (int i = begin; i < h; i++) {
                for (int j = 0; j < w; j++) {
                    if (data[i][j] != value) {
                        return i;
                    }
                }
            }
            return -1;
        }
    }
    int skipEntity(int begin, boolean isX, int value) {
        if (isX) {
            for (int i = begin; i < w; i++) {
                for (int j = 0; j < h; j++) {
                    if (data[j][i] == value) {
                        break;
                    }
                    if (j == h - 1)
                        return i;
                }
            }
            return -1;
        } else {
            for (int i = begin; i < h; i++) {

      
      
                for (int j = 0; j < w; j++) {
                    if (data[i][j] == value) {
                        break;
                    }
                    if (j == w - 1)
                        return i;
                }
            }
            return -1;
        }
    }
    class ImageIterator implements Iterator {
        int x;
        ImageData ia;
        ImageData next;
        public ImageIterator(ImageData ia) {
            this.ia = ia;
        }
        public boolean hasNext() {
            if (next != null)
                return true;
            next = getNext();
            return next != null;
        }
        ImageData getNext() {
            int x1 = skipEmpty(x, true, 0);
            if (x1 == -1) {
                return null;
            }
            int x2 = skipEntity(x1, true, 1);
            if (x2 == -1) {
                x2 = w;
            }
            x = x2;
            int y1 = skipEmpty(0, false, 0);
            if (y1 == -1)
                return null;
            int y2 = skipEntity(y1, false, 1);
            if (y2 == -1)
                y2 = h;
            return ia.clone(x1, y1, x2 - x1, y2 - y1);
        }
        public Object next() {
            ImageData temp = next;
            next = null;
            return temp;
        }
        public void remove() {
        }
    }
    ImageData clone(int x, int y, int w0, int h0) {
        ImageData ia = new ImageData();
        ia.w = w0;
        ia.h = h0;
        ia.data = new int[ia.h][ia.w];
        for (int i = 0; i < h0; i++) {
            for (int j = 0; j < w0; j++) {
                ia.data[i][j] = data[i + y][j + x];
            }
        }
        return ia;
    }
    public void show() {
        System.out.PRintln();
        for (int i = 0; i < h; i++) {
            for (int j = 0; j < w; j++) {
                System.out.print((data[i][j] == 1 ? "1" : " ") + "");
            }
            System.out.println();
        }
        System.out.println();
    }
    public int hashCode() {
        int code = w ^ h;
        int count = 0;
        for (int i = 0; i < h; i++) {
            for (int j = 0; j < w; j++) {
                if (data[i][j] == 1)
                    count++;
            }
        }
        code ^= count;
        return code;
    }
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj instanceof ImageData) {
            ImageData o = (ImageData) obj;
            if (o.h != h)
                return false;
            if (o.w != w)
                return false;
            for (int i = 0; i < h; i++) {
                for (int j = 0; j < w; j++) {
                    if (o.data[i][j] != data[i][j])
                        return false;
                }
            }
            return true;
        } else {
            return false;

      
      
        }
    }
    public static ImageData[] decodeFromFile(String path) throws IOException {
        BufferedReader reader = new BufferedReader(new FileReader(
                new File(path)));
        String line;
        ArrayList list = new ArrayList();
        while ((line = reader.readLine()) != null) {
            ImageData ia = decode(line);
            if (ia != null) {
                list.add(ia);
            }
        }
        return (ImageData[]) list.toArray(new ImageData[0]);
    }
    public static ImageData decode(String s) {
        String[] ss = s.split("\\,", 4);
        if (ss.length != 4)
            return null;
        if (ss[0].length() != 1)
            return null;
        ImageData ia = new ImageData();
        ia.code = ss[0].charAt(0);
        ia.w = Integer.parseInt(ss[1]);
        ia.h = Integer.parseInt(ss[2]);
        if (ss[3].length() != ia.w * ia.h) {
            return null;
        }
        ia.data = new int[ia.h][ia.w];
        for (int i = 0; i < ia.h; i++) {
            for (int j = 0; j < ia.w; j++) {
                if (ss[3].charAt(i * ia.w + j) =='1') {
                    ia.data[i][j] = 1;
                } else {
                    ia.data[i][j] = 0;
                }
            }
        }
        return ia;
    }
    public String encode() {
        StringBuffer sb = new StringBuffer();
        sb.append(code).append(",");
        sb.append(w).append(",");
        sb.append(h).append(",");
        for (int i = 0; i < h; i++) {
            for (int j = 0; j < w; j++) {
                if (data[i][j] == 1) {
                    sb.append('1');
                } else {
                    sb.append('0');
                }
            }
        }
        return sb.toString();
    }
}
//像素过滤接口
package pay365;
public interface Filter {
    
    void doFilter(int[][] data);
}
//
package pay365;
public abstract class AbstractFilter  implements Filter {
    public void doFilter(int[][] data) {
        int h = data.length;
        if (h<=0)
            return;
        int w = data[0].length;
        if (w<=0)
            return ;
        for(int i=0;i< h;i++) {
            for(int j=0;j< w;j++) {
                data[i][j] = filter(data[i][j]);
            }
        }
    }
    
    protected abstract int filter(int p);
}
//过滤csdn验证码的过滤器
package pay365;
public class CsdnFilter extends AbstractFilter {
    protected int filter(int p) {
        return isNotWhite(p)?1:0;
    }
    private boolean isNotWhite(int p) {
        boolean b = (p & 0×0ff) == 255 && (p >> 8 & 0×0ff) == 255
                && (p >> 16 & 0xff) == 255;
        return !b;
    }
}
//过滤前景色为白色的过滤器
package pay365;
public class WhiteFilter extends AbstractFilter {
    
    protected int filter(int p) {
        if (isWhite(p)) {
            return 1;
        }
        else {
            return 0;

      
      
        }
    }
    private boolean isWhite(int p) {
        return (p & 0x0ff) > 240 && (p >> 8 & 0x0ff) > 240
                && (p >> 16 & 0xff) > 240;
    }
}
//模板创建类
package pay365;
import java.awt.image.BufferedImage;
import java.io.BufferedReader;
import java.io.File;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.URL;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;
import javax.imageio.ImageIO;
public class TemplateCreator {
    /**
     * @param args
     */
    public static void main(String[] args) throws Exception {
        Set set = new HashSet();
        
        String url = "http://passport.csdn.net/member/ShowEXPwd.aspx";
        String filterClazz = "pay365.CsdnFilter";
        if (args.length>=1) {
            url = args[0];
        }
        if (args.length>=2) {
            filterClazz = args[1];
        }
        Filter csdnFilter = (Filter) Class.forName(filterClazz).newInstance();
        for (int i = 1; i < 10; i++) {
            URL u = new URL(url);
            BufferedImage bi = ImageIO.read(u);
            ImageData ia2 = new ImageData(bi,csdnFilter);
            ImageData[] ii = ia2.split();
            for (int x = 0; x < ii.length; x++) {
                ImageData imageArr = ii[x];
                set.add(imageArr);
            }
            // set.addAll(Arrays.asList(ia2.split()));
        }
        System.out.println(set.size());
        for (Iterator iter = set.iterator(); iter.hasNext();) {
            ImageData ele = (ImageData) iter.next();
            ele.show();
            System.out.print("char:");
            String s = readLine();
            if (s.length() == 1) {
                ele.code = s.charAt(0);
            }
        }
        
        PrintWriter pw = new PrintWriter(new File("template.data"));
        for (Iterator iter = set.iterator(); iter.hasNext();) {
            ImageData ele = (ImageData) iter.next();
            pw.println(ele.encode());
        }
        pw.flush();
        pw.close();
    }
    private static BufferedReader reader = new BufferedReader(
            new InputStreamReader(System.in));
    private static String readLine() {
        try {
            return reader.readLine();
        } catch (Exception e) {
            e.printStackTrace();
            return "";
        }
    }
}
//识别类
package pay365;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import javax.imageio.ImageIO;
public class Recognize2 {
    static String url = "http://passport.csdn.net/member/ShowExPwd.aspx";
    static Filter filter;

      
      
    public static void main(String[] args) throws Exception {
        if (args.length >= 1) {
            url = args[0];
        }
        String filterClazz = "pay365.CsdnFilter";
        if (args.length >= 2) {
            filterClazz = args[1];
        }
        filter = (Filter) Class.forName(filterClazz).newInstance();
        int total = 10;
        int count = 0;
        for (int i = 0; i < total; i++) {
            boolean b = recognize(i);
            if (b)
                count++;
        }
        System.out.println("rate:" + (count * 1.0 / total * 100) + "%100");
    }
    /**
     * @throws IOException
     */
    private static boolean recognize(int num) throws IOException {
        BufferedImage bi = ImageIO.read(new URL(url));
        ImageIO.write(bi,"png",new File(num+".png"));
        ImageData ia2 = new ImageData(bi, filter);
        ImageData[] ii = ia2.split();
        ArrayList list = new ArrayList();
        ImageData[] template = ImageData.decodeFromFile("template.data");
        HashMap map = new HashMap();
        for (int i = 0; i < template.length; i++) {
            map.put(template[i], new Character(template[i].code));
        }
        for (int x = 0; x < ii.length; x++) {
            ImageData imageArr = ii[x];
            if (imageArr.w > 15)
                continue;
            Character c = (Character) map.get(imageArr);
            if (c != null) {
                list.add(c);
            }
        }
        String s = "";
        System.out.print(num + ":");
        for (Iterator iter = list.iterator(); iter.hasNext();) {
            Character c = (Character) iter.next();
            s += c;
            System.out.print(c);
        }
        System.out.println();
        return s.length() != 0;
    }
}

（出处：http://www.cncms.com）