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Designing Human Friendly Human Interaction Proofs (HIPs). Kumar Chellapilla, Kevin Larson, Patrice Simard and Mary Czerwinski Microsoft Research Presented by Shaohua Xie March 22, 2005. OUTLINE. Introduction Definitions User Study I User Study II Conclusion References. Introduction. - PowerPoint PPT Presentation
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Designing Human FriendlyHuman Interaction Proofs
(HIPs)
Kumar Chellapilla, Kevin Larson, Patrice Simard and Mary Czerwinski
Microsoft Research
Presented by Shaohua XieMarch 22, 2005
Introduction
HIPs, or Human Interactive Proofs, are challenges meant to be easily solved by humans, while remaining too hard to be economically solved by computers.
An example character based HIP
Introduction
HIPs are increasingly used to protect services against automatic script attacks.
Mailblocks HIP samples.
User Study I HIPs that only varied on one parameter of
distortion are presented to users.
Accuracy: the percentage of characters correctly recognized.
For the parameter levels tested on plain, translated, rotated or scaled text HIPs, users were at 99% correct or higher.
User Study II
Unidimensional HIPs has been systematically broken, with a success rate of 5% or greater at a rate of 300 attempts per second [2,12].
Arcs and baselines are added to make HIPs very hard for computers to break.
Conclusion Most one-dimensional HIPs are easy for users to
solve. However, there is a significant decrease in human
HIP solution accuracy with the increase of the global or local warping levels.
Accuracy was also quite high across all levels of HIP recognition with thin arcs in the foreground.
Adding intersecting thick arcs caused significant performance decrements, but non-intersecting thick arcs did not.
References1. Simard PY, Szeliski R, Benaloh J, Couvreur J, and Calinov I (2003), “Using
Character Recognition and Segmentation to Tell Computers from Humans,”International Conference on Document Analysis and Recognition (ICDAR), IEEE Computer Society, pp. 418-423, 2003.
2. Chellapilla K., and Simard P., “Using Machine Learning to Break Visual Human Interaction Proofs (HIPs),” Advances in Neural Information Processing Systems 17, Neural Information Processing Systems (NIPS’2004), MIT Press.
3. Turing AM (1950), “Computing Machinery and Intelligence,” Mind, vol. 59, no. 236, pp. 433-460.
4. Von Ahn L, Blum M, and Langford J. (2004) “Telling Computers and Humans Apart (Automatically) or How Lazy Cryptographers do AI.” Comm. of the ACM ,47(2):56-60.
5. First Workshop on Human Interactive Proofs, Palo Alto, CA, January 2002.6. Von Ahn L, Blum M, and Langford J, The Captcha Project.
http://www.captcha.net
References7. Mori G, Malik J (2003), “Recognizing Objects in Adversarial Clutter:
Breaking a Visual CAPTCHA,” Proceedings of the Computer Vision and Pattern Recognition (CVPR) Conference, IEEE Computer Society, vol.1, pages:I-134 - I-141, June 18-20, 2003
8. Chew, M. and Baird, H. S. (2003), “BaffleText: a Human Interactive Proof,” Proc., 10th IS&T/SPIE Document Recognition & Retrieval Conf., Santa Clara, CA, Jan. 22.
9. Simard, P.,Y., Steinkraus, D., Platt, J. (2003) “Best Practice for Convolutional Neural Networks Applied to Visual Document Analysis,” International Conference on Document Analysis and Recognition (ICDAR), IEEE Computer Society, Los Alamitos, pp. 958-962, 2003.
10. Selfridge, O.G. (1959). Pandemonium: A paradigm for learning. In Symposium in the mechanization of thought process (pp.513-526). London: HM Stationery Office.
11. Pelli, D. G., Burns, C. W., Farrell, B., & Moore, D. C, “Identifying letters.” (accepted) Vision Research.
12. Goodman J. and Rounthwaite R., “Stopping Outgoing Spam,” Proc. of the 5th ACM conf. on Electronic commerce, New York, NY. 2004.