Captcha OCR solver?
- Thread starter qxxxp
- Start date
qxxxp
Junior Member
- May 3, 2009
- 186
- 82
I dont need a seo software, I am writing a seo software myself - I need a source code, or a component (.NET / ActiveX) for automatic captcha solving.. or at least any hints for the algorithm
Idea in captcha cracking is to clean up image and then run it through an OCR such as Tesseract (my preference) or Gocr. You might also have to train the OCR to work better with whatever font the captcha is using.
Cleaning up the image refers to removing stuff such as lines that intersect with characters or background noise.
I recommend you use C#.
Useful links that I started with(covers almost everything you need):
http://code.google.com/p/aforge/
http://www.codeproject.com/KB/dotnet/simple_ocr.aspx
http://www.brains-n-brawn.com/default.aspx?vDir=aicaptcha
Good tutorial on neural networks:
http://www.ai-junkie.com/ann/evolved/nnt1.html
Note: I started with neural networks, but I find that in a lot of cases templates based off of offsets in the character and with specified margins of error for each character work a lot better. Be aware of the tradeoffs in between the two approaches.
Cleaning up the image refers to removing stuff such as lines that intersect with characters or background noise.
I recommend you use C#.
Useful links that I started with(covers almost everything you need):
http://code.google.com/p/aforge/
http://www.codeproject.com/KB/dotnet/simple_ocr.aspx
http://www.brains-n-brawn.com/default.aspx?vDir=aicaptcha
Good tutorial on neural networks:
http://www.ai-junkie.com/ann/evolved/nnt1.html
Note: I started with neural networks, but I find that in a lot of cases templates based off of offsets in the character and with specified margins of error for each character work a lot better. Be aware of the tradeoffs in between the two approaches.
kelvin.thechamp
Senior Member
- Apr 4, 2011
- 931
- 356
Use open CV or Open CV c# wrapper or Afroge .net libraries for image processing
if u want any other language libraries let me know i have good exp in image processing working on Recaptcha Ocr now..
if u want any other language libraries let me know i have good exp in image processing working on Recaptcha Ocr now..
If you're interested in using python, someone was doing their PhD dissertation on cracking captchas. You can find their examples, research, and findings at a website called wausita. (can't give the full url due to newbie status -- sorry)
A simple pixel by pixel analytics program for images in python can be achieved in only a few lines using the PIL (python image libraries).
If you aren't a programmer, I found a question on Stackoverflow about reCaptcha cracks. The page has a submitted answer with 54 likes for a website called captchakiller which provides a captcha breaking API.
This solution offers a RESTful API (meaning instead of importing a library, you can just curl or make requests to the API via the HTTP protocol.
A simple pixel by pixel analytics program for images in python can be achieved in only a few lines using the PIL (python image libraries).
Code:
from PIL import Image[FONT=monospace]
[/FONT]im = Image.open("captcha.gif")[FONT=monospace]
[/FONT]im = im.convert("P")
print im.histogram()If you aren't a programmer, I found a question on Stackoverflow about reCaptcha cracks. The page has a submitted answer with 54 likes for a website called captchakiller which provides a captcha breaking API.
This solution offers a RESTful API (meaning instead of importing a library, you can just curl or make requests to the API via the HTTP protocol.
Last edited:
licorne101
Registered Member
- Aug 22, 2011
- 95
- 123
These are very useful. Thanks for the introduction. I will try and implement them into my programs.
I think it probably requires a lot more work than just using the API though. I want to build a learning capability so it improves itself.
I think it probably requires a lot more work than just using the API though. I want to build a learning capability so it improves itself.
plumbum416
Junior Member
- Mar 17, 2011
- 112
- 24
You could also use a captcha-breaking service. I'm writing a bot in Java right now and for example recaptcha has a top api and gives you the code to use it in nearly every programming language (well at least the established ones, no such exots like "brainfuck" 
)
)The Data Guy
Junior Member
- Mar 24, 2010
- 153
- 45
Use train a neural network to recognize bineized characters(semi hard part) + Char Segmentation(really hard part) + loads of other secret things you must discover on your own because you will not be spoon feed(very easy part)= ocr