How to Use Command to Automate Data Extraction with CAPTCHA Handling

Are you a developer looking to integrate Optical Character Recognition (OCR) to retrieve text from images in your applications, or a user interested in using mobile scanners equipped with OCR technology? This article will guide you through the process of automating data extraction and dealing with CAPTCHA blocking. We will discuss the advantages of using an OCR SDK and the configuration of manual or automatic CAPTCHA handling with Content Grabber.

OCR SDK Integration

If you are a developer, you can leverage more advanced OCR SDKs such as those from Yunmai Technology to integrate OCR capabilities into your applications. For users, mobile scanners equipped with OCR technology can easily extract text from images, making the process more accessible.

CAPTCHA Blocking Implementation

When building or managing websites, implement CAPTCHA blocking using a web form that requires users to submit the form to access restricted areas of the site. This form typically includes an image element and a text box element where users must enter characters as they appear in the image. While humans can easily read the text in the CAPTCHA image, web-scraping agents face challenges due to the need for specialized character recognition software.

Manual and Automatic CAPTCHA Handling

Manual CAPTCHA Configuration:

Configuring manual CAPTCHA handling allows you to pause the agent and manually decode the CAPTCHA image. To do this, you would:

Add a Pause Agent command to your agent script to pause the execution when a CAPTCHA image is detected. Select the CAPTCHA image element in the web browser to set the web selection for the command. Configure the command to automatically submit the form after the user enters the CAPTCHA text or let the user submit the form.

If CAPTCHA blocking is part of a larger registration form, you can process the CAPTCHA manually and let the agent handle the remaining form automatically, submitting it upon completion.

Automatic CAPTCHA Configuration:

For fully automated CAPTCHA handling, you need to set up an account with a third-party CAPTCHA recognition service and configure your agent accordingly. Here are the steps:

Create a group of commands specifically for CAPTCHA handling. Use an Exit Command to skip CAPTCHA processing if the image is not found. Download the CAPTCHA image and use an OCR script to decode it. Set the form field with the decoded text. Submit the form and retry CAPTCHA processing if necessary.

The command group should be added to all locations in your agent where CAPTCHA blocking is likely to occur.

OCR Scripts for CAPTCHA Decoding

Content Grabber provides API and standard OCR scripts that call CAPTCHA recognition services such as Death by CAPTCHA and Bypass CAPTCHA for decoding. Here is an example of an OCR script using the Death by CAPTCHA service:

public static string ConvertImageToText(ConvertImageToTextArguments args) {    string captcha  DeathByCapTCHA.Login   captcha;    return captcha;}

In the script, replace the login and password with those provided by Death by CAPTCHA.

Troubleshooting CAPTCHA Issues

If you encounter issues with CAPTCHA handling despite correct entries, it might be due to the downloading process of the CAPTCHA image. To resolve this, use a Download Screenshot command instead of a Download Image command, as it avoids the need for a second download, potentially bypassing server restrictions.

Keyword: CAPTCHA, OCR SDK, Content Grabber