Automatic OCR language detection with tesseract

Detect language automatically with Tesseract OCR and force full-page OCR.

What this example does

• Configures Tesseract (CLI in this snippet) with lang=["auto"].
• Forces full-page OCR and prints the recognized text as Markdown.

How to run

• From the repo root: python docs/examples/tesseract_lang_detection.py.
• Ensure Tesseract CLI (or library) is installed and on PATH.

Notes

• You can switch to TesseractOcrOptions instead of TesseractCliOcrOptions.
• Language packs must be installed; set TESSDATA_PREFIX if Tesseract cannot find language data. Using lang=["auto"] requires traineddata that supports script/language detection on your system.

In [ ]:

from pathlib import Path

from docling.datamodel.base_models import InputFormat
from docling.datamodel.pipeline_options import (
    PdfPipelineOptions,
    TesseractCliOcrOptions,
)
from docling.document_converter import DocumentConverter, PdfFormatOption


def main():
    data_folder = Path(__file__).parent / "../../tests/data"
    input_doc_path = data_folder / "pdf/2206.01062.pdf"

    # Set lang=["auto"] with a tesseract OCR engine: TesseractOcrOptions, TesseractCliOcrOptions
    # ocr_options = TesseractOcrOptions(lang=["auto"])
    ocr_options = TesseractCliOcrOptions(lang=["auto"])

    pipeline_options = PdfPipelineOptions(
        do_ocr=True, force_full_page_ocr=True, ocr_options=ocr_options
    )

    converter = DocumentConverter(
        format_options={
            InputFormat.PDF: PdfFormatOption(
                pipeline_options=pipeline_options,
            )
        }
    )

    doc = converter.convert(input_doc_path).document
    md = doc.export_to_markdown()
    print(md)


if __name__ == "__main__":
    main()

from pathlib import Path from docling.datamodel.base_models import InputFormat from docling.datamodel.pipeline_options import ( PdfPipelineOptions, TesseractCliOcrOptions, ) from docling.document_converter import DocumentConverter, PdfFormatOption def main(): data_folder = Path(__file__).parent / "../../tests/data" input_doc_path = data_folder / "pdf/2206.01062.pdf" # Set lang=["auto"] with a tesseract OCR engine: TesseractOcrOptions, TesseractCliOcrOptions # ocr_options = TesseractOcrOptions(lang=["auto"]) ocr_options = TesseractCliOcrOptions(lang=["auto"]) pipeline_options = PdfPipelineOptions( do_ocr=True, force_full_page_ocr=True, ocr_options=ocr_options ) converter = DocumentConverter( format_options={ InputFormat.PDF: PdfFormatOption( pipeline_options=pipeline_options, ) } ) doc = converter.convert(input_doc_path).document md = doc.export_to_markdown() print(md) if __name__ == "__main__": main()