Need help with SDK for creating new Captcha profile

michaelu715

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:



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

and after that I calculated the masks:

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

Sven

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)?

michaelu715

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?

Sven

no way to less in case of a rotating captcha. You would need many many more to get it better.

michaelu715

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?

Sven

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.

michaelu715

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?

mashafeeq

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