An Audio CAPTCHA to Distinguish Humans from Computers

  title={An Audio CAPTCHA to Distinguish Humans from Computers},
  author={Haichang Gao and Honggang Liu and Dan Yao and Xiyang Liu and Uwe Aickelin},
  journal={2010 Third International Symposium on Electronic Commerce and Security},
CAPTCHAs are employed as a security measure to differentiate human users from bots. A new sound-based CAPTCHA is proposed in this paper, which exploits the gaps between human voice and synthetic voice rather than relays on the auditory perception of human. The user is required to read out a given sentence, which is selected randomly from a specified book. The generated audio file will be analyzed automatically to judge whether the user is a human or not. In this paper, the design of the new… 

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