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    Tesseract.js

    Pure Javascript OCR for 62 Languages 📖🎉🖥
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    • 🕩2020
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    Tesseract.js

    Lint & Test CodeQL Gitpod Ready-to-Code Financial Contributors on Open Collective npm version Maintenance License Code Style Downloads Month

    Tesseract.js is a javascript library that gets words in almost any language out of images. (Demo)

    Image Recognition

    fancy demo gif

    Video Real-time Recognition

    Tesseract.js Video

    Tesseract.js wraps a webassembly port of the Tesseract OCR Engine. It works in the browser using webpack or plain script tags with a CDN and on the server with Node.js. After you install it, using it is as simple as:

    import Tesseract from 'tesseract.js';
    
    Tesseract.recognize(
      'https://tesseract.projectnaptha.com/img/eng_bw.png',
      'eng',
      { logger: m => console.log(m) }
    ).then(({ data: { text } }) => {
      console.log(text);
    })
    

    Or more imperative

    import { createWorker } from 'tesseract.js';
    
    const worker = await createWorker({
      logger: m => console.log(m)
    });
    
    (async () => {
      await worker.loadLanguage('eng');
      await worker.initialize('eng');
      const { data: { text } } = await worker.recognize('https://tesseract.projectnaptha.com/img/eng_bw.png');
      console.log(text);
      await worker.terminate();
    })();
    

    Check out the docs for a full explanation of the API.

    Major changes in v4

    Version 4 includes many new features and bug fixes--see this issue for a full list. Several highlights are below.

    • Added rotation preprocessing options (including auto-rotate) for significantly better accuracy
    • Processed images (rotated, grayscale, binary) can now be retrieved
    • Improved support for parallel processing (schedulers)
    • Breaking changes:
      • createWorker is now async
      • getPDF function replaced by pdf recognize option

    Major changes in v3

    • Significantly faster performance
      • Runtime reduction of 84% for Browser and 96% for Node.js when recognizing the example images
    • Upgrade to Tesseract v5.1.0 (using emscripten 3.1.18)
    • Added SIMD-enabled build for supported devices
    • Added support:
      • Node.js version 18
    • Removed support:
      • ASM.js version, any other old versions of Tesseract.js-core (<3.0.0)
      • Node.js versions 10 and 12

    Major changes in v2

    • Upgrade to tesseract v4.1.1 (using emscripten 1.39.10 upstream)
    • Support multiple languages at the same time, eg: eng+chi_tra for English and Traditional Chinese
    • Supported image formats: png, jpg, bmp, pbm
    • Support WebAssembly (fallback to ASM.js when browser doesn't support)
    • Support Typescript

    Read a story about v2: Why I refactor tesseract.js v2?
    Check the support/1.x branch for version 1

    Installation

    Tesseract.js works with a <script> tag via local copy or CDN, with webpack via npm and on Node.js with npm/yarn.

    CDN

    <!-- v4 -->
    <script src='https://unpkg.com/tesseract.js@4.0.2/dist/tesseract.min.js'></script>
    

    After including the script the Tesseract variable will be globally available.

    Node.js

    Requires Node.js v14 or higher

    # For latest version
    npm install tesseract.js
    yarn add tesseract.js
    
    # For old versions
    npm install tesseract.js@3.0.3
    yarn add tesseract.js@3.0.3
    

    Documentation

    Use tesseract.js the way you like!

    React Native is not supported as it does not support Webassembly.

    Disclaimer: These examples are now several years old and use old versions of both Tesseract.js and the relevant frameworks. Users are encouraged to use the latest version of Tesseract.js rather than the versions used in these examples. For users that update these examples (or make new ones), please consider contributing through a PR.

    Contributing

    Development

    To run a development copy of Tesseract.js do the following:

    # First we clone the repository
    git clone https://github.com/naptha/tesseract.js.git
    cd tesseract.js
    
    # Then we install the dependencies
    npm install
    
    # And finally we start the development server
    npm start
    

    The development server will be available at http://localhost:3000/examples/browser/demo.html in your favorite browser. It will automatically rebuild tesseract.dev.js and worker.dev.js when you change files in the src folder.

    Online Setup with a single Click

    You can use Gitpod(A free online VS Code like IDE) for contributing. With a single click it will launch a ready to code workspace with the build & start scripts already in process and within a few seconds it will spin up the dev server so that you can start contributing straight away without wasting any time.

    Open in Gitpod

    Building Static Files

    To build the compiled static files just execute the following:

    npm run build
    

    This will output the files into the dist directory.

    Contributors

    Code Contributors

    This project exists thanks to all the people who contribute. [Contribute].

    Financial Contributors

    Become a financial contributor and help us sustain our community. [Contribute]

    Individuals

    Organizations

    Support this project with your organization. Your logo will show up here with a link to your website. [Contribute]

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