Click here to Skip to main content
13,000,742 members (66,782 online)
Rate this:
Please Sign up or sign in to vote.
See more:
Hi all,

My question is "Is it possible to decode captcha code?" I mean whatever code is displayed in captcha image, can we take it in variable?

If yes can anyone please explain how is it be done? Or can provide any sample code?

Second, I dont wnat to use any third party dll or something else.

Thanks in advance.
Posted 20-Oct-10 2:05am
tiggerc 20-Oct-10 10:53am
I don't like where this request is going, Captcha has been created for a reason, primarily to stop people creating applications to signup for things.
I'm in agreement with answer 1, If there was a way it would probably not be public knowledge and they would make Captcha's harder to read.
Rate this: bad
Please Sign up or sign in to vote.

Solution 1

If you are trying to reverse a Captcha image to the text it needs entered, then probably not - they are designed that way to make OCR difficult if not impossible. Not only that, but there is a variant of Captcha called reCaptcha which uses humans to do the OCR of text that OCR software could not de-code. This is used as part of various projects, notably to digitize the whole of the New York Times.

If there was a way, Captchas would immediately become much harder to prevent your software from working! :laugh:
Rate this: bad
Please Sign up or sign in to vote.

Solution 4

If you don't want to use any third party dll, you probably need to pay some one to develop something as complex as this, and as others have said, the simple fact that you're trying to defeat what captcha is written for, means that it's designed to make it hard for you, so you're likely to fail, at least some times.
Rate this: bad
Please Sign up or sign in to vote.

Solution 3

There are two answers to this question.

"Yes", depending on the image implementation. Some are easier to decode than others.

"Absolutely NOT!" You're not getting any help with doing this at all, for obvious reasons, and that you'll be screwing with the accuracy of other digitizing projects.
Marcus Kramer 13-Nov-12 16:33pm
I'll try not to mention that this question is over 2 years old.... (Oops, did I say that out loud?)
Dave Kreskowiak 13-Nov-12 17:04pm
Whoops! Looks like CHristian got bit by it too.

For some reason, this question got popped back up to the top of the Q&A page...

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

  Print Answers RSS
Top Experts
Last 24hrsThis month

Advertise | Privacy | Mobile
Web02 | 2.8.170624.1 | Last Updated 13 Nov 2012
Copyright © CodeProject, 1999-2017
All Rights Reserved. Terms of Service
Layout: fixed | fluid

CodeProject, 503-250 Ferrand Drive Toronto Ontario, M3C 3G8 Canada +1 416-849-8900 x 100