Page 205 - CITS - Computer Software Application -TT

COMPUTER SOFTWARE APPLICATION - CITS

2 Create and Output the CAPTCHA Image:

In this code snippet, we use the GD library to create an image with a specified background color, set text color,
and place the random text on the image. The image is then output as PNG.
3 Embed the CAPTCHA in HTML:

Include this HTML code on your form page to display the generated CAPTCHA image.
4 Validate the Entered Text:

Upon form submission, retrieve the entered text and validate it against the stored value in the session.

Security Considerations:
• Randomness: Ensure the generated text is sufficiently random to challenge automated scripts effectively.

• Length and Complexity: Adjust the length and complexity of the generated text based on the desired security
level.
• Session Storage: Store the generated CAPTCHA text securely in the session to validate it during form
submission.
Implementing a text-based CAPTCHA adds an additional layer of security to your PHP forms, reducing the risk
of automated submissions and enhancing the overall security of your web application.

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CITS : IT&ITES - Computer Software Application - Lesson 47 - 62