When tasked with downloading decades of monthly GIS data from a restricted website, I encountered aggressive CAPTCHA challenges that blocked batch downloads. As a lazy GIS professional unwilling to perform repetitive manual downloads, I developed an automated solution.
Tool Introduction
ddddocr (GitHub: https://github.com/sml2h3/ddddocr)
This open-source OCR library specializes in CAPTCHA recognition. Its pre-trained models effectively decode various CAPTCHA types without custom training.
Implementation
For immediate deployment:
- Use the FastAPI wrapper: https://github.com/sml2h3/ddddocr-fastapi
- Deploy via Docker or Python environment
Deployment Note: Basic Python knowledge required (troubleshooting with GPT/Google recommended)
Validation Results: 
After 72 hours of continuous testing:
- Success rate: >95%
- Zero manual intervention
- Full dataset acquired
Advanced Applications
Handles complex CAPTCHA types including:
- Rotated text
- Distorted characters
- Background noise interference
Custom model training documentation available in repository
Important Considerations
- Automation Justification: Reserve for large-scale, repetitive downloads only
- Legal Compliance: Ensure adherence to website terms of service and local regulations
- Ethical Use: Obtain proper authorization before scraping protected resources