How to transcribe old documents with AI help

Old genealogical documents present challenges that go beyond ordinary reading:

• Historical cursive handwriting: Kurrent (used in Germanic documents until the 1940s), 19th-century Italian script and Portuguese chancery hand have letter forms very different from today's.
• Non-standardized abbreviations: each priest or notary had their own abbreviations.
• Ecclesiastical Latin: many parish records prior to the 20th century were written in Latin.
• Physical deterioration: moisture stains, holes, faded ink and paper folds make any reading difficult.
• Multiple entries per page: parish records often have 3 to 8 entries per page without clear separation.

AI can help in three complementary ways:

1. OCR adapted for historical documents: modern computer vision models (such as Gemini Vision) can interpret cursive scripts far better than conventional OCR on handwritten documents. The result is a preliminary transcription — not perfect, but sufficient for identifying fields and names.

2. Structured extraction: beyond transcribing the text, AI identifies which parts correspond to each field (name, date, location, kinship). This saves complete reading time when the researcher only needs the main fields.

3. Variant normalization: common names have multiple historical spellings (Surname A / variant A1 / variant A2; Surname B / variant B1; Surname C / variant C1). AI can group variants of the same surname and cross-reference occurrences across different documents.

1. Quality scanning: the scan should have at least 200–300 DPI. Mobile camera scans with poor lighting greatly reduce transcription quality.
2. Document type identification: telling the system whether it is a baptism, marriage, death or other record type helps the AI use the correct field schema.
3. Initial extraction: the AI produces a preliminary transcription with identified fields. Names, dates and locations are the first candidates.
4. Researcher review: the AI transcription is a starting point, not a final result. The researcher corrects incorrect readings and fills in fields the AI could not identify.
5. Cross-referencing with other sources: with corrected fields, it is possible to cross-reference with other documents to confirm dates, kinship and locations.

• Kurrent: German cursive with very specific letter forms. Letters like 'n', 'u', 'm' and 'i' are nearly identical without context.
• Suetterlin: simplified variant of Kurrent, used in German schools until 1941.
• Colonial Brazilian scripts: mix of Portuguese, Italian and Germanic influences depending on region and period.
• Abbreviated ecclesiastical Latin: standard Latin ritual formulas often appeared abbreviated differently by region.