Improve OCR performance

[SeanPedersen]

Tesseract:

• https://github.com/tesseract-ocr/tesseract/issues/263#issuecomment-536197289

Even better: Find a solid GPU accelerated OCR implementation:

• https://github.com/jaidedai/easyocr (looks promising but rly aweful CPU performance and too big model sizes for my lil GPU with 2GB VRAM)
• https://github.com/Xilinx/pytorch-ocr/blob/master/README.md
• https://github.com/Calamari-OCR/calamari
• https://github.com/faustomorales/keras-ocr