java验证码识别--4

最新推荐文章于 2025-01-27 09:28:01 发布

原创最新推荐文章于 2025-01-27 09:28:01 发布 · 3.1w 阅读

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文章标签：

#java #exception #string #file #bi

本文介绍了一种使用Java进行验证码识别的方法，通过去除干扰线、分割字符等预处理步骤，最终实现约85%的识别准确率。文中详细展示了代码实现过程，并提供了完整的Eclipse工程供下载。

java验证码识别--1

http://blog.youkuaiyun.com/problc/article/details/5794460

java验证码识别--2

http://blog.youkuaiyun.com/problc/article/details/5797507

java验证码识别--3

http://blog.youkuaiyun.com/problc/article/details/5800093

java验证码识别--4

http://blog.youkuaiyun.com/problc/article/details/5846614

java验证码识别--5

http://blog.youkuaiyun.com/problc/article/details/5983276

(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。)

完整eclipse工程http://download.youkuaiyun.com/detail/problc/3829004

验证码识别如果识别率都是100%，那验证码也就没存在的必要了。

其实很多验证码能达到10%的识别率就不错了。

下面来一个稍微复杂一点的，识别率85%左右。

看验证码

挑一张来看

放大看，我们会发现干扰线是纯黑色的，因此去干扰线的方法就有了

对点color[i][j],如果color[i+1][j],color[i-1][j],color[i][j+1],color[i][j-1]都是纯黑或者纯白色的，就认为color[i][j]是干扰，将color[i][j]置为白色。

处理之后

这样就简单了，分割也简单。

识别结果

啥也不说了，贴代码

public class ImagePreProcess4 { private static Map<BufferedImage, String> trainMap = null; private static int index = 0; public static int isBlack(int colorInt) { Color color = new Color(colorInt); if (color.getRed() + color.getGreen() + color.getBlue() <= 300) { return 1; } return 0; } public static int isWhite(int colorInt) { Color color = new Color(colorInt); if (color.getRed() + color.getGreen() + color.getBlue() > 300) { return 1; } return 0; } public static int getColorBright(int colorInt) { Color color = new Color(colorInt); return color.getRed() + color.getGreen() + color.getBlue(); } public static int isBlackOrWhite(int colorInt) { if (getColorBright(colorInt) < 30 || getColorBright(colorInt) > 730) { 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 = 1; x < width - 1; ++x) { for (int y = 1; y < height - 1; ++y) { if (getColorBright(img.getRGB(x, y)) < 100) { if (isBlackOrWhite(img.getRGB(x - 1, y)) + isBlackOrWhite(img.getRGB(x + 1, y)) + isBlackOrWhite(img.getRGB(x, y - 1)) + isBlackOrWhite(img.getRGB(x, y + 1)) == 4) { img.setRGB(x, y, Color.WHITE.getRGB()); } } } } for (int x = 1; x < width - 1; ++x) { for (int y = 1; y < height - 1; ++y) { if (getColorBright(img.getRGB(x, y)) < 100) { if (isBlackOrWhite(img.getRGB(x - 1, y)) + isBlackOrWhite(img.getRGB(x + 1, y)) + isBlackOrWhite(img.getRGB(x, y - 1)) + isBlackOrWhite(img.getRGB(x, y + 1)) == 4) { img.setRGB(x, y, Color.WHITE.getRGB()); } } } } img = img.getSubimage(1, 1, img.getWidth() - 2, img.getHeight() - 2); return img; } public static BufferedImage removeBlank(BufferedImage img) throws Exception { int width = img.getWidth(); int height = img.getHeight(); int start = 0; int end = 0; Label1: for (int y = 0; y < height; ++y) { for (int x = 0; x < width; ++x) { if (isBlack(img.getRGB(x, y)) == 1) { start = y; break Label1; } } } Label2: for (int y = height - 1; y >= 0; --y) { for (int x = 0; x < width; ++x) { if (isBlack(img.getRGB(x, y)) == 1) { end = y; break Label2; } } } return img.getSubimage(0, start, width, end - start + 1); } public static List<BufferedImage> splitImage(BufferedImage img) throws Exception { List<BufferedImage> subImgs = new ArrayList<BufferedImage>(); int width = img.getWidth(); int height = img.getHeight(); List<Integer> weightlist = new ArrayList<Integer>(); for (int x = 0; x < width; ++x) { int count = 0; for (int y = 0; y < height; ++y) { if (isBlack(img.getRGB(x, y)) == 1) { count++; } } weightlist.add(count); } for (int i = 0; i < weightlist.size(); i++) { int length = 0; while (i < weightlist.size() && weightlist.get(i) > 0) { i++; length++; } if (length > 18) { subImgs.add(removeBlank(img.getSubimage(i - length, 0, length / 2, height))); subImgs.add(removeBlank(img.getSubimage(i - length / 2, 0, length / 2, height))); } else if (length > 5) { subImgs.add(removeBlank(img.getSubimage(i - length, 0, length, height))); } } return subImgs; } public static Map<BufferedImage, String> loadTrainData() throws Exception { if (trainMap == null) { Map<BufferedImage, String> map = new HashMap<BufferedImage, String>(); File dir = new File("train4"); File[] files = dir.listFiles(); for (File file : files) { map.put(ImageIO.read(file), file.getName().charAt(0) + ""); } trainMap = map; } return trainMap; } public static int getDistance(BufferedImage img, BufferedImage sample) { int width = img.getWidth(); int height = img.getHeight(); int count = 0; int widthmin = width < sample.getWidth() ? width : sample.getWidth(); int heightmin = height < sample.getHeight() ? height : sample .getHeight(); for (int x = 0; x < widthmin; ++x) { for (int y = 0; y < heightmin; ++y) { if (isWhite(img.getRGB(x, y)) != isWhite(sample.getRGB(x, y))) { count++; } } } return count; } public static boolean isNotEight(BufferedImage img) { int width = img.getWidth(); int height = img.getHeight(); int minCount = width; for (int y = height / 2 - 2; y < height / 2 + 2; ++y) { int count = 0; for (int x = 0; x < width / 2 + 2; ++x) { if (isBlack(img.getRGB(x, y)) == 1) { count++; } } minCount = Math.min(count, minCount); } return minCount < 2; } public static boolean isNotThree(BufferedImage img) { int width = img.getWidth(); int height = img.getHeight(); int minCount = width; for (int y = height / 2 - 3; y < height / 2 + 3; ++y) { int count = 0; for (int x = 0; x < width / 2 + 1; ++x) { if (isBlack(img.getRGB(x, y)) == 1) { count++; } } minCount = Math.min(count, minCount); } return minCount > 0; } public static boolean isNotFive(BufferedImage img) { int width = img.getWidth(); int height = img.getHeight(); int minCount = width; for (int y = 0; y < height / 3; ++y) { int count = 0; for (int x = width * 2 / 3; x < width; ++x) { if (isBlack(img.getRGB(x, y)) == 1) { count++; } } minCount = Math.min(count, minCount); } return minCount > 0; } public static String getSingleCharOcr(BufferedImage img, Map<BufferedImage, String> map) throws Exception { String result = "#"; int width = img.getWidth(); int height = img.getHeight(); int min = width * height; boolean bNotEight = isNotEight(img); boolean bNotThree = isNotThree(img); boolean bNotFive = isNotFive(img); for (BufferedImage bi : map.keySet()) { if (bNotThree && map.get(bi).startsWith("3")) continue; if (bNotEight && map.get(bi).startsWith("8")) continue; if (bNotFive && map.get(bi).startsWith("5")) continue; double count1 = getBlackCount(img); double count2 = getBlackCount(bi); if (Math.abs(count1 - count2) / Math.max(count1, count2) > 0.25) continue; int count = 0; if (width < bi.getWidth() && height < bi.getHeight()) { for (int m = 0; m <= bi.getWidth() - width; m++) { for (int n = 0; n <= bi.getHeight() - height; n++) { Label1: for (int x = m; x < m + width; ++x) { for (int y = n; y < n + height; ++y) { if (isWhite(img.getRGB(x - m, y - n)) != isWhite(bi .getRGB(x, y))) { count++; if (count >= min) break Label1; } } } } } } else { int widthmin = width < bi.getWidth() ? width : bi.getWidth(); int heightmin = height < bi.getHeight() ? height : bi .getHeight(); Label1: for (int x = 0; x < widthmin; ++x) { for (int y = 0; y < heightmin; ++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); } System.out.println(result); ImageIO.write(img, "JPG", new File("result4//" + result + ".jpg")); return result; } public static int getBlackCount(BufferedImage img) { int width = img.getWidth(); int height = img.getHeight(); int count = 0; for (int x = 0; x < width; ++x) { for (int y = 0; y < height; ++y) { if (isBlack(img.getRGB(x, y)) == 1) { count++; } } } return count; } public static void downloadImage() { HttpClient httpClient = new HttpClient(); GetMethod getMethod = new GetMethod( "http://reg.keepc.com/getcode/getCode.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 = "img4//" + i + ".jpg"; InputStream inputStream = getMethod.getResponseBodyAsStream(); OutputStream outStream = new FileOutputStream(picName); IOUtils.copy(inputStream, outStream); outStream.close(); System.out.println(i + "OK!"); } catch (Exception e) { e.printStackTrace(); } finally { // 释放连接 getMethod.releaseConnection(); } } } public static void trainData() throws Exception { File dir = new File("temp4"); File[] files = dir.listFiles(); for (File file : files) { BufferedImage img = removeBackgroud("temp4//" + file.getName()); List<BufferedImage> listImg = splitImage(img); if (listImg.size() == 4) { for (int j = 0; j < listImg.size(); ++j) { ImageIO.write(listImg.get(j), "JPG", new File("train4//" + file.getName().charAt(j) + "-" + (index++) + ".jpg")); } } } } /** * @param args * @throws Exception */ public static void main(String[] args) throws Exception { // downloadImage(); // trainData(); for (int i = 0; i < 30; ++i) { String text = getAllOcr("img4//" + i + ".jpg"); System.out.println(i + ".jpg = " + text); } } }