SwiftOCR: Fast and simple OCR library written in Swift
Ocrad: is an OCR (Optical Character Recognition) program based on a feature extraction method. It reads images in pbm (bitmap), pgm (greyscale) or ppm (color) formats and produces text in byte (8-bit) or UTF-8 formats.
awesome-ocr: A curated list of promising OCR resources.
2018-Dropbox-Using machine learning to index text from billions of images: So now, when a user searches for English text that appears in one of these files, it will show up in the search results. This blog post describes how we built this feature.