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![Can We Go With A Simple
Code?
For(int I=0; I<max;I++)
String[I]=(match.rand(48,90)+ match.rand(48,90))/2;
Const String p_string[]=string;
//save string
//function to convert text into bitmap image
Convert_ascii_to_image(string,captcha_image);
//function to rotate text
Rotate_image(image,match.random(15,45));
//function to add noise to image
add_noise_to_image(image);](https://image.slidesharecdn.com/captcha-suu-final-131116131234-phpapp01/75/Seminar-on-CAPTCHA-10-2048.jpg)
Uploaded bySuhas Joshi
Seminar on CAPTCHA
The seminar on CAPTCHA conducted by Mr. Suhas Joshi discussed its purpose as a challenge-response test that differentiates humans from computers. It covered the history of CAPTCHA, its algorithmic generation, applications, and potential drawbacks, such as lack of support for human disabilities and complexity in use. The conclusion emphasized the ongoing relevance of CAPTCHA in preventing automated abuses on the web, while also acknowledging the potential for future AI advancements to crack it.
Seminar on CAPTCHA
- 1. Seminar On: “CAPTCHA” By: Mr. SuhasJoshi. Under Guidance Of: Proff: V. B. Pagi. Basaveshwar Engineering College, Department Of Computer Application, Bagalkot.
- 2. What Is Captcha?… AnAutomated Test That: a) Most Humans Can Pass But, b) Current Computer Programs Can Not. That Is Captcha is a challenge test response used in computing to ensure that the response is generated by human being and not by computer.
- 3. You know CaptchaHistory? • The term "CAPTCHA" was coined in 2000 by Luis von Ahn, Manuel Blum, Nicholas J. Hopper (all of Carnegie Mellon University), and John Langford (then of IBM). • It Is Derived From TT. • Stands For: Completely Automated Public Turing Test to Tell Computers and Humans Apart.
- 4. What TT Is? •Is Suggested By Alan Turing In1950. • Used To replace Question: Can Machine Think? • The Test, very briefly put, is for an interrogator to decide whether a participant in a natural-language conversation is a human or a computer.
- 5. But, Captchas AreCompletely Automated. • Basic Turing Test consists of interrogator who use to conduct test. • But CAPTCHAs are completely automated. Computer (Servers) itself will generate a test, which them self can not capable of passing. • So, CAPTCHAs are alike Turing Test but interrogator in a turing test is replaced by computer which is programmed to test human level intelligence(By Some Methods)
- 6. Captcha is Public •It might seem like a bad idea to make the code of a captcha public. • If a captcha requires private data in order to be secure, then this captcha is easy to solve for hacker. • Must be hard to pass for all computers and not for those who don’t know some secret.
- 7. Some Examples!…. • Gimpy(Text Based On Image) • Bongo (Visual Pattern Recognition) • Pix (Large Image Data Base System) • Eco (Sound Based Captchas)
- 8. Lets Create Captcha •Lets try to create Simple Gimpy type Captcha with simple algorithm. • Algorithm is used to understand concept of captcha and may not fulfill today's requirements of captcha. • For more updated information please visit, http://www.captcha.net.
- 9. Algorithm to createcaptcha Step 1: START Step 2: Generate random characters, forming string. Step 3: Save String. Step 4: Convert String into Image Format. Step 5: Create Angle of Rotation (Rotate String). Step 6: Add Back-Ground Noise to image. Step 7: Save Captcha. Step 8: STOP
- 10. Can We GoWith A Simple Code? For(int I=0; I<max;I++) String[I]=(match.rand(48,90)+ match.rand(48,90))/2; Const String p_string[]=string; //save string //function to convert text into bitmap image Convert_ascii_to_image(string,captcha_image); //function to rotate text Rotate_image(image,match.random(15,45)); //function to add noise to image add_noise_to_image(image);
- 11. Captchas have great “APPLICATIONS” •Online Polls • Free Email Services • Search Engine Bots • Shopping Agents • Preventing Dictionary Attacks • Worms and Spam • Preventing Comment Spam in Blogs
- 12. Disadvantages Of Gimpy Captcha: •captcha which we have developed is having some serious drawbacks. I have revealed some of those where others are those which you are suffering while browsing some sites with registration form, which are asking you to solve difficult captcha before registration on net.
- 13. Continued…... • Not supportinghuman disabilities: • Human Solvers: • Stealing Cycles From Humans • Makes Sites Complex • Tedious Task
- 14. Conclusion • We arenow aware about captcha requirements in today’s word to protect abuse use of web. • Still captchas are not secured. • captcha is working because AI haven’t got perfect solution to solve this problem. • But there is a possibility that captchas will be cracked and unsolved AI problem may end up with solution.
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