50 lines
2 KiB
Markdown
50 lines
2 KiB
Markdown
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# OCR Language Packs and Setup
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This document provides instructions on how to add additional language packs for the OCR tab in Stirling-PDF, both inside and outside of Docker.
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## How does the OCR Work
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Stirling-PDF uses OCRmyPDF which in turn uses tesseract for its text recognition.
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All credit goes to them for this awesome work!
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## Language Packs
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Tesseract OCR supports a variety of languages. You can find additional language packs in the Tesseract GitHub repositories:
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- [tessdata_fast](https://github.com/tesseract-ocr/tessdata_fast): These language packs are smaller and faster to load, but may provide lower recognition accuracy.
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- [tessdata](https://github.com/tesseract-ocr/tessdata): These language packs are larger and provide better recognition accuracy, but may take longer to load.
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Depending on your requirements, you can choose the appropriate language pack for your use case. By default Stirling-PDF uses the tessdata_fast eng but this can be replaced.
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### Installing Language Packs
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1. Download the desired language pack(s) by selecting the `.traineddata` file(s) for the language(s) you need.
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2. Place the `.traineddata` files in the Tesseract tessdata directory: `/usr/share/tesseract-ocr/4.00/tessdata`
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#### Docker
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If you are using Docker, you need to expose the Tesseract tessdata directory as a volume in order to use the additional language packs.
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#### Docker Compose
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Modify your `docker-compose.yml` file to include the following volume configuration:
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```yaml
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services:
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your_service_name:
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image: your_docker_image_name
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volumes:
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- /usr/share/tesseract-ocr/4.00/tessdata:/location/of/trainingData
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```
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#### Docker run
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Add the following to your existing docker run command
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```bash
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-v /usr/share/tesseract-ocr/4.00/tessdata:/location/of/trainingData
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```
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#### Non-Docker
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If you are not using Docker, you need to install the OCR components, including the ocrmypdf app.
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You can see [OCRmyPDF install guide](https://ocrmypdf.readthedocs.io/en/latest/installation.html)
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