How to use OCR option in Linux/MacOs


As you know, PDF Focus .Net supports OCR. There are no difficulties in deploying on the Windows platform. However, if we are talking about Linux/MacOs, you need to make additional settings and the ability to convert scanned pdf documents will please you with its quality.

So, let's get started. Step by step.

  1. Download a latest version of PDF Focus .Net from NuGet in your project:
  2. You need to add additional dependencies in the project of Visual Studio:
    3. <PackageReference Include="SkiaSharp.NativeAssets.Linux" Version="2.88.7" />
<PackageReference Include="SkiaSharp.NativeAssets.macOS" Version="2.88.7" />
<PackageReference Include="HarfBuzzSharp.NativeAssets.Linux" Version="*" />
<PackageReference Include="HarfBuzzSharp.NativeAssets.macOS" Version="*" />
<PackageReference Include="System.Reflection.Emit" Version="*" />
    C#

    An example of full *.proj file:

  3. To install Tesseract 5.x you can simply run the following command on your Linux/macOS:
    4. sudo apt install tesseract-ocr
    Tesseract uses Leptonica.
    Leptonica is a pedagogically-oriented open source library containing software that is broadly useful for image processing and image analysis applications.
    sudo apt install libleptonica-dev
    If you wish to install the Developer Tools which can be used for training, run the following command:
    sudo apt install libtesseract-dev
    The following instructions are for building on Linux, which also can be applied to other UNIX like operating systems.
  • Now, you need to add some code for converting scanned PDF to editable Word document:
    • Please be sure, that you specify the correct path for the folder “tessdata”.
    “OcrLanguage” must be installed like your original PDF document: Eng, Ger, Fra, etc. Once your project is launched, all dependencies will be downloaded and additional folders will be added to the debug folder:

    Important! Because Tesseract is configured to control the Windows OS, you need to manually add two files to the “x64” folder:

    Libleptonica-1.82.0.so
    libtesseract50.so

    You need to download it from the Internet or our full code sample for OCR Linux/MacOs:

  • After you have done the above steps. Run the last command in the terminal: "dotnet restore" and "dotnet run":
    • The result of the conversion will be an editable Word-file that you can edit and save.

    The full code sample you may download directly from GitHub in C#: The link

    If you need a new code example or have a question: email us at support@sautinsoft.com or ask at Online Chat (right-bottom corner of this page).