Need help with SDK for creating new Captcha profile

Hi,

I know that I can request a new capture type but I want to learn how do do it by myself with that amazing piece of software :)

Here you have a few sample images:
image


And a few more zipped: Download

Do you think that' s a hard one to work on ? Any success rate more than 50% would be very nice.


I read all the tutorials I could find but most of them suggest using Brute Force at the end which unfortuantely didn' t work for me so far.

Now I want to try it with masks.

I use a filter like
image
and after that I calculated the masks:
image
Now I have obviously 100% for all the Captchas in my list, but when I add more, none of them are recognized correctly.

I am wondering if this is the way to go ? Play around with the filters to calculate some "better" masks? Or do I just have a bad Captcha type which isn' t so easy to deal with?

Sorry for all the noob questions but I am very new into this.

Greets

Michael

Comments

  • SvenSven www.GSA-Online.de
    the mask algorithem is a good idea. However since this captcha rotates the chars and the -segment-rotate is not always correct with rotation, you end up with a lot variations of the same char. So it's required to add a lot variations of the same char and make a mask from it. How many do you have for now (use stats)?
  • When I generate the masks with 33 Captchas:
     Character | Masks count
    -----------+-------------
         A     |  6
         B     | 14
         C     | 18
         D     | 10
         E     |  8
         F     | 13
         G     |  9
         H     | 11
         I     |  7
         J     |  8
         K     |  5
         L     |  7
         M     |  4
         N     |  8
         O     |  6
         P     |  5
         Q     |  3
         R     |  8
         T     |  8
         U     |  2
         V     |  7
         W     |  7
         X     |  5
         Y     |  7
    -----------+-------------
               | = 186

    With 77 Captchas:
     Character | Masks count
    -----------+-------------
         A     | 15
         B     | 18
         C     | 27
         D     | 20
         E     | 23
         F     | 20
         G     | 20
         H     | 28
         I     | 21
         J     | 21
         K     | 19
         L     | 20
         M     | 20
         N     | 25
         O     | 19
         P     | 12
         Q     | 10
         R     | 15
         S     |  2
         T     | 21
         U     | 13
         V     | 16
         W     | 17
         X     | 14
         Y     |  9
    -----------+-------------
               | = 445

    These are way too much masks, right?
  • SvenSven www.GSA-Online.de
    no way to less in case of a rotating captcha. You would need many many more to get it better.
  • Can you be more specific ? If I would have 200 masks for each character would that be enough? As I wrote before a 50% success rate would be great.

    Maybe one interesting fact:
    I can generate as much different captchas for the same 6 chars as I want because when I refresh a URL with a specific captcha key I get a different looking captcha every time. Can that help me to get better results somehow?
  • SvenSven www.GSA-Online.de
    hmm yea that would help as you can quickly download a lot variations of same char without having to read/answer it.
    Anyway 200 per char is really good...maybe even too much.
  • Ok thank you! Then I will try optimizing 6 chars with a lot of captchas first before moving on. Should I continue with the segment-rotate-filter or should I just use segment?
  • will u just have to create more and more >>> one of my captchas i used over 3000 sample to create the best definition for it
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