Everything about CAPTCHA

🧭 Start here: a 6-step reading path

1. Read the overview: CAPTCHAA 5-minute orientation
2. Skim a recent paper: Vessel-CAPTCHA: An efficient learning framework for vessel annotation and segmentationInfluential work since 2022
3. Pick up a classic book: The Great CloudwallThe most-reprinted book on the subject
4. Read the landmark paper: No Bot Expects the DeepCAPTCHA! Introducing Immutable Adversarial Examples, With Applications to CAPTCHA GenerationCited 154 times
5. Go sideways: ReCAPTCHAA closely related topic
6. Go sideways: Proof of personhoodA closely related topic

🏆 Landmark papers (most cited)

• No Bot Expects the DeepCAPTCHA! Introducing Immutable Adversarial Examples, With Applications to CAPTCHA Generation

  Margarita Osadchy, Julio Hernandez-Castro, Stuart Gibson · 2017 · IEEE Transactions on Information Forensics and Security · 154 citations

• Research on Deep Learning Techniques in Breaking Text-Based Captchas and Designing Image-Based Captcha

  Mengyun Tang, Haichang Gao, Yang Zhang · 2018 · IEEE Transactions on Information Forensics and Security · 91 citations

• CAPTCHA recognition based on deep convolutional neural network

  Jing Wang, College of Computer Science and Information Technology, Central South University of Forestry and Technology, 498 shaoshan S Rd, Changsha, 410004, China, Jiaohua Qin · 2019 · Mathematical Biosciences and Engineering · 73 citations

• Captcha as Graphical Passwords—A New Security Primitive Based on Hard AI Problems

  Bin B. Zhu, Jeff Yan, Guanbo Bao · 2014 · IEEE Transactions on Information Forensics and Security · 69 citations

• Research on the Security of Microsoft’s Two-Layer Captcha

  Haichang Gao, Mengyun Tang, Yi Liu · 2017 · IEEE Transactions on Information Forensics and Security · 62 citations

• Gotta CAPTCHA ’Em All: A Survey of 20 Years of the Human-or-computer Dilemma

  Meriem Guerar, Luca Verderame, Mauro Migliardi · 2021 · ACM Computing Surveys · 52 citations

• FaceDCAPTCHA: Face detection based color image CAPTCHA

  Gaurav Goswami, Brian M. Powell, Mayank Vatsa · 2014 · Future Generation Computer Systems · 51 citations

• A new implementation of chaotic S-boxes in CAPTCHA

  Majid Khan, Tariq Shah, Syeda Iram Batool · 2015 · Signal, Image and Video Processing · 51 citations

🆕 Influential since 2022

• Vessel-CAPTCHA: An efficient learning framework for vessel annotation and segmentation

  Vien Ngoc Dang, Francesco Galati, Rosa Cortese · 2022 · Medical Image Analysis · 49 citations

• Recent advances of Captcha security analysis: a short literature review

  Nghia Trong Dinh, Vinh Truong Hoang · 2023 · Procedia Computer Science · 41 citations

• Engineering Graphical Captcha and AES Crypto Hash Functions for Secure Online Authentication

  Nafisah Kheshaifaty, Adnan Gutub · 2023 · Journal of Engineering Research · 39 citations

• Counteracting Dark Web Text-Based CAPTCHA with Generative Adversarial Learning for Proactive Cyber Threat Intelligence

  Ning Zhang, Mohammadreza Ebrahimi, Weifeng Li · 2022 · ACM Transactions on Management Information Systems · 31 citations

• An Experimental Investigation of Text-based CAPTCHA Attacks and Their Robustness

  Ping Wang, Haichang Gao, Xiaoyan Guo · 2023 · ACM Computing Surveys · 26 citations

📚 Books worth reading

• The Great CloudwallJeffrey Cliff · 2020
• 📕Come vedereDanilo Sirianni · 2017
• 📕ClickTiffany Babb · 2020

Ranked by number of editions on Open Library, a rough measure of how lasting a book is.

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