Hi guys,
there is currently a lot of interest in OCR technology for automatic text extraction, but in some cases more effort is needed to create an OCR module that produces a really high-quality result.
One of such cases is engineering drawings, which are very difficult to recognize. This article provides an overview of free and paid tools available for integration for these tasks. I hope you'll find it insightful.
https://mobidev.biz/blog/ocr-system-development-blueprints-engineering-drawings