Kraken.io vs Tesseract OCR: What are the differences?
Developers describe Kraken.io as "Image optimization and compression API". Kraken supports JPEG, PNG and GIF files. You can optimize your images in two ways - by providing an URL of the image you want to optimize or by uploading an image file directly to Kraken API. On the other hand, Tesseract OCR is detailed as "Tesseract Open Source OCR Engine". Tesseract was originally developed at Hewlett-Packard Laboratories Bristol and at Hewlett-Packard Co, Greeley Colorado between 1985 and 1994, with some more changes made in 1996 to port to Windows, and some C++izing in 1998. In 2005 Tesseract was open sourced by HP. Since 2006 it is developed by Google.
Kraken.io can be classified as a tool in the "Image Processing and Management" category, while Tesseract OCR is grouped under "Image Analysis API".
Tesseract OCR is an open source tool with 27.8K GitHub stars and 5.31K GitHub forks. Here's a link to Tesseract OCR's open source repository on GitHub.
AWS Rekognition has an OCR feature but can recognize only up to 50 words per image, which is a deal-breaker for us. (see my tweet).
Also, we discovered fantastic speed and quality improvements in the 4.x versions of Tesseract. Meanwhile, the quality of AWS Rekognition's OCR remains to be mediocre in comparison.
Worth mentioning that we run Tesseract in AWS Lambda via aws-lambda-tesseract library.