java验证码识别--1

(本文仅用于学习研究图像匹配识别原理，不得用于其他用途。)

最近看了看验证码的识别，先从最简单的做起吧(固定大小，固定位置，固定字体)

 

验证码识别基本分四步，图片预处理，分割，训练，识别

 

看一个最简单验证码

这是一个德克萨斯扑克的注册页面的验证码

 

1。图像的预处理

这种直接根据亮度设个阈值处理就可以了

public static int isWhite(int colorInt) { Color color = new Color(colorInt); if (color.getRed() + color.getGreen() + color.getBlue() > 100) { return 1; } return 0; } public static BufferedImage removeBackgroud(String picFile) throws Exception { BufferedImage img = ImageIO.read(new File(picFile)); int width = img.getWidth(); int height = img.getHeight(); for (int x = 0; x < width; ++x) { for (int y = 0; y < height; ++y) { if (isWhite(img.getRGB(x, y)) == 1) { img.setRGB(x, y, Color.WHITE.getRGB()); } else { img.setRGB(x, y, Color.BLACK.getRGB()); } } } return img; }

 

处理完图片效果为

图像基本分得比较清楚，图片分割也比较容易

 

2。分割

这个验证码居然是固定位置的，分割相当简单，直接截取相应位置就可以了

public static List<BufferedImage> splitImage(BufferedImage img) throws Exception { List<BufferedImage> subImgs = new ArrayList<BufferedImage>(); subImgs.add(img.getSubimage(10, 6, 8, 10)); subImgs.add(img.getSubimage(19, 6, 8, 10)); subImgs.add(img.getSubimage(28, 6, 8, 10)); subImgs.add(img.getSubimage(37, 6, 8, 10)); return subImgs; }

3。训练

直接拿几张图片，包含0-9，每个数字一个样本就可以了，将文件名对应相应的数字

4。识别

因为是固定大小，固定位置，识别也很简单。

直接拿分割的图片跟这个十个图片一个像素一个像素的比，相同的点最多的就是结果。比如如果跟5.jpg最相似，那么识别的结果就是5。

下面是识别结果，很容易达到100%

 

 

完整代码(csdn连个附件都不支持)：

import java.awt.Color; import java.awt.image.BufferedImage; import java.io.File; import java.io.FileOutputStream; import java.io.InputStream; import java.io.OutputStream; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import javax.imageio.ImageIO; import org.apache.commons.httpclient.HttpClient; import org.apache.commons.httpclient.HttpStatus; import org.apache.commons.httpclient.methods.GetMethod; import org.apache.commons.io.IOUtils; public class ImagePreProcess { public static int isWhite(int colorInt) { Color color = new Color(colorInt); if (color.getRed() + color.getGreen() + color.getBlue() > 100) { return 1; } return 0; } public static int isBlack(int colorInt) { Color color = new Color(colorInt); if (color.getRed() + color.getGreen() + color.getBlue() <= 100) { return 1; } return 0; } public static BufferedImage removeBackgroud(String picFile) throws Exception { BufferedImage img = ImageIO.read(new File(picFile)); int width = img.getWidth(); int height = img.getHeight(); for (int x = 0; x < width; ++x) { for (int y = 0; y < height; ++y) { if (isWhite(img.getRGB(x, y)) == 1) { img.setRGB(x, y, Color.WHITE.getRGB()); } else { img.setRGB(x, y, Color.BLACK.getRGB()); } } } return img; } public static List<BufferedImage> splitImage(BufferedImage img) throws Exception { List<BufferedImage> subImgs = new ArrayList<BufferedImage>(); subImgs.add(img.getSubimage(10, 6, 8, 10)); subImgs.add(img.getSubimage(19, 6, 8, 10)); subImgs.add(img.getSubimage(28, 6, 8, 10)); subImgs.add(img.getSubimage(37, 6, 8, 10)); return subImgs; } public static Map<BufferedImage, String> loadTrainData() throws Exception { Map<BufferedImage, String> map = new HashMap<BufferedImage, String>(); File dir = new File("train"); File[] files = dir.listFiles(); for (File file : files) { map.put(ImageIO.read(file), file.getName().charAt(0) + ""); } return map; } public static String getSingleCharOcr(BufferedImage img, Map<BufferedImage, String> map) { String result = ""; int width = img.getWidth(); int height = img.getHeight(); int min = width * height; for (BufferedImage bi : map.keySet()) { int count = 0; Label1: for (int x = 0; x < width; ++x) { for (int y = 0; y < height; ++y) { if (isWhite(img.getRGB(x, y)) != isWhite(bi.getRGB(x, y))) { count++; if (count >= min) break Label1; } } } if (count < min) { min = count; result = map.get(bi); } } return result; } public static String getAllOcr(String file) throws Exception { BufferedImage img = removeBackgroud(file); List<BufferedImage> listImg = splitImage(img); Map<BufferedImage, String> map = loadTrainData(); String result = ""; for (BufferedImage bi : listImg) { result += getSingleCharOcr(bi, map); } ImageIO.write(img, "JPG", new File("result//"+result+".jpg")); return result; } public static void downloadImage() { HttpClient httpClient = new HttpClient(); GetMethod getMethod = new GetMethod( "http://www.puke888.com/authimg.php"); for (int i = 0; i < 30; i++) { try { // 执行getMethod int statusCode = httpClient.executeMethod(getMethod); if (statusCode != HttpStatus.SC_OK) { System.err.println("Method failed: " + getMethod.getStatusLine()); } // 读取内容 String picName = "img//" + i + ".jpg"; InputStream inputStream = getMethod.getResponseBodyAsStream(); OutputStream outStream = new FileOutputStream(picName); IOUtils.copy(inputStream, outStream); outStream.close(); System.out.println("OK!"); } catch (Exception e) { e.printStackTrace(); } finally { // 释放连接 getMethod.releaseConnection(); } } } /** * @param args * @throws Exception */ public static void main(String[] args) throws Exception { for (int i = 0; i < 30; ++i) { String text = getAllOcr("img//" + i + ".jpg"); System.out.println(i + ".jpg = " + text); } } }