Datasets:

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eacl26-detect-latin

The dataset contains 724 annotated historical document pages. 594 pages contain Latin and 130 pages do not. The data is designed for page-level Latin detection and Latin segment extraction from OCR text and page images.

Source Files

The Zenodo record contains:

File	Size	Checksum
`latin_annotation_final.json`	6,176,204 bytes	`md5:f7dd7b59c2ba90832bfa7f5e2fc16976`
`images.zip`	52,835,690 bytes	`md5:a1f4d0e1ed78561e137ae276d75a89ff`

Recommended Hugging Face Layout

README.md
DATASET_SPEC.md
data/
  pages.jsonl
  latin_annotation_final.json
images.zip

pages.jsonl is the normalized, viewer-friendly file. latin_annotation_final.json preserves the original annotation export. images.zip preserves the original image bundle.

Normalized Record Schema

Each line in data/pages.jsonl is a JSON object:

Field	Type	Description
`page_id`	string	Stable page id, `<ecco_id>_<page_number>`.
`ecco_id`	string	ECCO source identifier.
`page_number`	integer or string	Page number from the source item.
`image_path`	string	Relative image path, e.g. `images/0213801900_151.jpg`.
`has_latin`	boolean	`true` when `page_latin` is non-empty.
`page_text`	string	Original OCR text from the `pageText` field.
`page_text_clean`	string	LLM-corrected OCR text from the `pageTextClean` field.
`page_latin`	string	Latin text associated with the page.
`latin_regions`	list[object]	Bounding boxes for Latin regions.
`latin_spans`	list[object]	Text-span labels for Latin segments.

`latin_regions`

Each region object has:

Field	Type	Description
`x`	float	Left coordinate as percentage of image width.
`y`	float	Top coordinate as percentage of image height.
`width`	float	Box width as percentage of image width.
`height`	float	Box height as percentage of image height.
`rotation`	float	Rotation value from the annotation tool.
`labels`	list[string]	Region labels. All released region annotations use `["Latin"]`.
`original_width`	integer	Original image width in pixels.
`original_height`	integer	Original image height in pixels.

`latin_spans`

Each span object has:

Field	Type	Description
`start`	integer	Start character offset in the annotated text field.
`end`	integer	End character offset in the annotated text field.
`text`	string	Annotated Latin text span.
`labels`	list[string]	Fine-grained Latin use labels.

Observed Label Distribution

Text-span labels:

Label	Count
Direct Quote	389
Independent	230
Footnote	192
Code-switching	183
Side-note	81
Bilingual	55
Emblematic	38
Legal	31
Indices and Catalogs	30
Ecclesiastical	23
Tables and Charts	10
Dictionary	9
Unlocatable	5

The original export contains 2,310 Latin bounding-box annotations.

Splits

No train/validation/test split is included in the released dataset. The release contains all 724 annotated pages as a single benchmark set. Any derived split should be reported by downstream users.

Known Caveats

OCR text is noisy, reflecting the historical print source and OCR pipeline.
Image paths in the JSON are relative to the extracted images/ directory.
The data is licensed for non-commercial use only.