java - 如何使用 Selenium WebDriver 和 Java 从图像中读取文本(验证码)

Question

我有注册网页，但最后显示验证码。

我无法从图像中读取文本。我将提及代码和输出..

@Test
public void loginTest() throws InterruptedException {
    System.out.println("Testing");
    driver.get("https://customer.onlinelic.in/ForgotPwd.htm");

    WebElement element = driver.findElement(By.xpath("//*[@id='forgotPassword']/table/tbody/tr[5]/td[3]/img"));
    System.out.println(" get the instance ");

    String elementTest = element.getAttribute("src");
    System.out.println("Element : " + elementTest);
}

输出:错误

Exception in thread "main" org.openqa.selenium.NoSuchElementException: Unable to locate element: {"method":"xpath","selector":"//[@id='forgotPassword']/table/tbody/tr[5]/td[3]/img"} Command duration or timeout: 60.02 seconds For documentation on this error, please visit: http://seleniumhq.org/exceptions/no_such_element.html Build info: version: '2.35.0', revision: '8df0c6b', time: '2013-08-12 15:43:19' System info: os.name: 'Windows 7', os.arch: 'amd64', os.version: '6.1', java.version: '1.6.0_26' Session ID: 5f5b2e1a-56a4-49ad-8fd3-2870747a7768 Driver info: org.openqa.selenium.firefox.FirefoxDriver Capabilities [{platform=XP, acceptSslCerts=true, javascriptEnabled=true, browserName=firefox, rotatable=false, locationContextEnabled=true, version=23.0.1, cssSelectorsEnabled=true, databaseEnabled=true, handlesAlerts=true, browserConnectionEnabled=true, nativeEvents=true, webStorageEnabled=true, applicationCacheEnabled=true, takesScreenshot=true}] at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) at java.lang.reflect.Constructor.newInstance(Constructor.java:513) at org.openqa.selenium.remote.ErrorHandler.createThrowable(ErrorHandler.java:191) at org.openqa.selenium.remote.ErrorHandler.throwIfResponseFailed(ErrorHandler.java:145) at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:554) at org.openqa.selenium.remote.RemoteWebDriver.findElement(RemoteWebDriver.java:307) at org.openqa.selenium.remote.RemoteWebDriver.findElementByXPath(RemoteWebDriver.java:404) at org.openqa.selenium.By$ByXPath.findElement(By.java:344) at org.openqa.selenium.remote.RemoteWebDriver.findElement(RemoteWebDriver.java:299) at seleniumtest.CaptchaTest.loginTest(CaptchaTest.java:41) at seleniumtest.CaptchaTest.main(CaptchaTest.java:59) Caused by: org.openqa.selenium.remote.ErrorHandler$UnknownServerException: Unable to locate element: {"method":"xpath","selector":"//[@id='forgotPassword']/table/tbody/tr[5]/td[3]/img"} Build info: version: '2.35.0', revision: '8df0c6b', time: '2013-08-12 15:43:19' System info: os.name: 'Windows 7', os.arch: 'amd64', os.version: '6.1', java.version: '1.6.0_26' Driver info: driver.version: unknown at .FirefoxDriver.prototype.findElementInternal_(file:///C:/Users/lukup/AppData/Local/Temp/anonymous4043037924964932185webdriver-profile/extensions/fxdriver@googlecode.com/components/driver_component.js:8880) at .fxdriver.Timer.prototype.setTimeout/<.notify(file:///C:/Users/lukup/AppData/Local/Temp/anonymous4043037924964932185webdriver-profile/extensions/fxdriver@googlecode.com/components/driver_component.js:396)

Answer 1

为了详细说明之前的答案，CAPTCHA 是“完全自动化的公共(public)图灵测试来区分计算机和人类”的缩写。所以，如果“机器”能解决它，它并没有真正完成它的工作。

为了解决这个问题，你可以做一些事情 - 使用外部服务的API，例如 http://www.deathbycaptcha.com 。您实现他们的 API，向他们传递验证码并返回文本。我观察到的平均求解时间约为 10-15 秒。

实现示例(取自 here )

import com.DeathByCaptcha.AccessDeniedException;
import com.DeathByCaptcha.Captcha;
import com.DeathByCaptcha.Client;
import com.DeathByCaptcha.SocketClient;
import com.DeathByCaptcha.HttpClient;

/* Put your DeathByCaptcha account username and password here.
   Use HttpClient for HTTP API. */
Client client = (Client)new SocketClient(username, password);
try {
    double balance = client.getBalance();

    /* Put your CAPTCHA file name, or file object, or arbitrary input stream,
       or an array of bytes, and optional solving timeout (in seconds) here: */
    Captcha captcha = client.decode(captchaFileName, timeout);
    if (null != captcha) {
        /* The CAPTCHA was solved; captcha.id property holds its numeric ID,
           and captcha.text holds its text. */
        System.out.println("CAPTCHA " + captcha.id + " solved: " + captcha.text);

        if (/* check if the CAPTCHA was incorrectly solved */) {
            client.report(captcha);
        }
    }
} catch (AccessDeniedException e) {
    /* Access to DBC API denied, check your credentials and/or balance */
}