Tesseract for node.js

A simple wrapper for the Tesseract OCR package for node.js

Requirements

• Tesseract 3.01 or higher is needed for this to work

Installation

There is a hard dependency on the Tesseract project. You can find installation instructions for various platforms on the project site. For Homebrew users, the installation is quick and easy.

brew install tesseract --all-languages

The above will install all of the language packages available, if you don't need them all you can remove the --all-languages flag and install them manually, by downloading them to your local machine and then exposing the TESSDATA_PREFIX variable into your path:

export TESSDATA_PREFIX=~/Downloads/

You can then go about installing the node-module to expose the JavaScript API:

npm install node-tesseract

Usage

var tesseract = require('node-tesseract');

// Recognize text of any language in any format
tesseract.process(__dirname + '/path/to/image.jpg',function(err, text) {
	if(err) {
		console.error(err);
	} else {
		console.log(text);
	}
});

// Recognize German text in a single uniform block of text and set the binary path

var options = {
	l: 'deu',
	psm: 6,
	binary: '/usr/local/bin/tesseract'
};

tesseract.process(__dirname + '/path/to/image.jpg', options, function(err, text) {
	if(err) {
		console.error(err);
	} else {
		console.log(text);
	}
});

Changelog

• 0.2.7: Adds output file extension detection
• 0.2.6: Catches exception when deleting tmp files that do not exist
• 0.2.5: Preserves whitespace and replaces tmp module
• 0.2.4: Removes console logging for messaging
• 0.2.3: The ability to set the binary path via the config object. Better installation documentation.
• 0.2.2: Adds test converage to utils module
• 0.2.1: Strips leading & trailing whitespace from output by default
• 0.2.0: Adds ability to pass options via a configuration object.
• 0.1.1: Updates tmp module.
• 0.1.0: Removes preprocessing functionatlity. See #3.
• 0.0.3: Adds basic test coverage for process method
• 0.0.2: Pulls in changes by joscha including: refactored to support tesseract 3.01, added language parameter, config parameter, documentation, Added support for custom preprocessors, OTB Preprocessor using ImageMagick 'convert'
• 0.0.1: Initial version