Captcha recognition with Deep learning

Architecture

CNN architecture inspired by yolo9000, but far less complicated.

Network predict 13x12 vector. Each row correspond to one of 13 detectors. Each detector provide:

• [0] Confidence of detector
• [1:10] One-hot encoded digit
• [11] Offset of digit from center of current detector

Achived accuracy for 3 digits: ~99%.

Acknowledgments

Network topology visualized by http://alexlenail.me/NN-SVG

Captcha based on python captcha module https://github.com/lepture/captcha. Original captcha module was modified to generate ground truth data.

Yolo9000 https://pjreddie.com/publications/yolo9000/