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How can find percentage of recognition per sample

FnasserFnasser
in GSA Captcha Breaker
I am trying to break a CAPTCHA scheme using the SDK. How can I find the partially recognized character of each samples. 
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  • SvenSven www.GSA-Online.de
    You need to enter the results for each captcha in order for the SDK to train things and decide what filter get you the best results.
  • SvenSven www.GSA-Online.de
    https://docu.gsa-online.de/captcha_breaker/tutorials#sdk
  • FnasserFnasser
    Sven said:
    https://docu.gsa-online.de/captcha_breaker/tutorials#sdk
    Sven said:
    You need to enter the results for each captcha in order for the SDK to train things and decide what filter get you the best results.
    I have followed the instructions. And I have entered the correct answer for each sample. Now I wanted the percentage for the recognized character. (I want to calculate how many number in this sample were solved correctly)  
  • SvenSven www.GSA-Online.de
    well click TEST...but did you previously use BruteForce to find a solution automatically? Thats usually the best and easiest way.
  • FnasserFnasser
    Sven said:
    well click TEST...but did you previously use BruteForce to find a solution automatically? Thats usually the best and easiest way.
    Yes. How can I find the OCR results per characters? I read a paper and they used the GSA breaker to break CAPTCHA samples. The authors indicated the partial recognition success (which means number of correctly recognized characters by GSA). I would like to follow their methodology, so how can I get the OCR results per characters?    
  • SvenSven www.GSA-Online.de
    You probably mean the SDK option with the segmentation filter and the "Use Masks" option? Show me that paper to get a clue what they are talking about.
  • FnasserFnasser
    Sven said:
    You probably mean the SDK option with the segmentation filter and the "Use Masks" option? Show me that paper to get a clue what they are talking about.

    This is the paper link: https://www.sciencedirect.com/science/article/pii/S016740481730161X

    "By calculating the weighted average values of all CRSRs at a specific ORO level (for example, 30%), the partial computer recognition success rate value was calculated (for example, 28%). At this ORO level, there are 4 occurrences where the CRSR equals 100%, where the entire CAPTCHA string was correctly recognised, corresponding to 20 recognised characters. There is one instance each for the CRSR equalling 80% (four correctly recognised characters), 60% (three correctly recognised characters), and 20% (one correctly recognised character).Thus, in a total of 20 trials (each containing five characters), 28 characters were correctly recognised (i.e. 28%)."

    CRSR: computer recognition success rate.

  • SvenSven www.GSA-Online.de
    Im afraid this has nothing to do with GSA Captcha Breaker. They just use OCR here but it's not related to captchas in general.
  • FnasserFnasser
    Sven said:
    Im afraid this has nothing to do with GSA Captcha Breaker. They just use OCR here but it's not related to captchas in general.
    They mentioned that the results were obtained from the GSA-Captcha Breaker
  • SvenSven www.GSA-Online.de
    Oh I see...well maybe it'S easier if you show me the captcha you want to have supported and I show you the best way to add it...might be good to do this as a tutorial as well for others.
  • FnasserFnasser


    I would like to test different types of BotDetect CAPTCHAs. These are two examples.
    I want to test how many CAPTCHA were recognized correctly. If it was not recognized how many letters were recognized correctly by GSA.  
  • SvenSven www.GSA-Online.de
    OK now I understood. However, the given samples are very hard to solve for the software due to the 2 colors and the switch of for/background. It's very easy for us humans to read this but almost impossible for Captcha Breaker.
    However, I can try adding a stats showing how many letters have been correctly recognized if that is of any interest for you.
    Because it is not really for the final result. If just one character is wrong, it's simply a complete wrong answer for given and so the solution is wrong.
  • FnasserFnasser
    Sven said:
    OK now I understood. However, the given samples are very hard to solve for the software due to the 2 colors and the switch of for/background. It's very easy for us humans to read this but almost impossible for Captcha Breaker.
    However, I can try adding a stats showing how many letters have been correctly recognized if that is of any interest for you.
    Because it is not really for the final result. If just one character is wrong, it's simply a complete wrong answer for given and so the solution is wrong.
    That is what I wanted to measure (how many letters have been correctly recognized by the GSA?) 
  • SvenSven www.GSA-Online.de
    next update will have the letter statistics as well once you test things.
  • FnasserFnasser
    Great!! When it will be available?  
  • SvenSven www.GSA-Online.de
    Im releasing an update now.
  • FnasserFnasser
    Wow! Great
    Thank you very much 
  • FnasserFnasser
    Sven said:
    next update will have the letter statistics as well once you test things.
    How can I find letter statistics? I updated the GSA but I couldn't find them 
  • SvenSven www.GSA-Online.de
    click TEST and in the popup you get the results.
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