Rahvusarhiiv/et_handwriting_complete

Dataset of Full PAGE XML and ALTO Annotations in Handwritten Estonian Documents

Dataset Description

This dataset contains full page-level Transkribus exports from Estonian historical documents. Each example pairs a full page image with the corresponding PAGE XML and ALTO XML for the same page, preserving document structure, layout coordinates, reading order, baselines, and text content where available.

The dataset is intended for OCR research, layout analysis, document structure modelling, XML parsing, and conversion benchmarking between document analysis formats.

📊 Dataset Summary

• Total Examples: 7,664 pages
• Language: 🇪🇪 Estonian
• Dataset Size: ~20.1 GB
• Task: OCR, Layout Analysis, Document Structure Analysis, XML Parsing
• Domain: Historical Documents, Archival Materials

🗂️ Dataset Structure

📋 Features

• image: Full page image (PIL Image)
• page: Full PAGE XML as a UTF-8 string
• alto: Full ALTO XML as a UTF-8 string
• document_title: Source document name
• AIS_reference: AIS file reference number
• page_number: Location of frame in file

🎯 XML Formats

The dataset stores the original XML content as readable strings.

PAGE XML contains page metadata, reading order, text regions, text lines, coordinates, baselines, and text content:

<PcGts ...>
  <Page imageFilename="..." imageWidth="5472" imageHeight="3648">
    <ReadingOrder>...</ReadingOrder>
    <TextRegion ...>
      <Coords points="..."/>
      <TextLine ...>
        <Coords points="..."/>
        <Baseline points="..."/>
        <TextEquiv>
          <Unicode>...</Unicode>
        </TextEquiv>
      </TextLine>
    </TextRegion>
  </Page>
</PcGts>

ALTO XML contains layout blocks, text lines, token-level strings, and page-level image metadata:

<alto ...>
  <Layout>
    <Page WIDTH="5472" HEIGHT="3648">
      <PrintSpace>
        <TextBlock>
          <TextLine>
            <String CONTENT="..."/>
          </TextLine>
        </TextBlock>
      </PrintSpace>
    </Page>
  </Layout>
</alto>

🔧 Technical Details

XML Standards

• PAGE XML follows the PAGE schema used by Transkribus exports
• ALTO XML follows the ALTO schema for OCR and layout representation
• Both XML fields are stored as full strings and can be parsed with standard XML tooling

Coordinate System

• Coordinates are expressed in pixel space relative to the full page image
• The origin (0,0) is at the top-left corner
• PAGE XML includes polygon coordinates and baselines
• ALTO XML includes page and layout geometry in the same page coordinate space

Data Processing

• Extracted from Transkribus exports
• Full XML content preserved instead of flattening annotations into simpler fields
• Images are stored alongside their corresponding XML representations
• Document metadata is retained through document_title, AIS_reference, and page_number

⚠️ Data Quality Notes

• Image quality varies depending on the preservation state of the historical documents
• XML quality depends on the original Transkribus annotations and export pipeline
• Some pages may contain irregular layouts, overlapping regions, or complex handwriting
• PAGE XML and ALTO XML represent the same page but may differ in structure and granularity

🚫 Limitations

• Limited to Estonian language historical documents
• Data is stored as raw XML strings, so downstream use typically requires XML parsing
• Historical handwriting and scan quality may affect OCR and layout consistency
• Some pages may contain incomplete, noisy, or inconsistent annotations

📞 Contact

Depending on the nature of your question, please contact one of the following:

• Content of dataset: @svlp or @LudwigRoine
• Format or anything technical: @paulpall
• For everything else: the National Archives of Estonia.

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