LocalDoc/azerbaijani-ocr-lines

Azerbaijani OCR Lines

Line-level training data for Azerbaijani text recognition, in Latin and Cyrillic script, extracted from scanned books.

Fields

field	description
image	cropped text line, grayscale, height 48 px
text	transcription
script	az_latin or az_cyrillic
book	anonymised source-book id

How it was built

Pages come from scanned PDFs that already carried an OCR text layer. Line boxes were taken from that layer, rendered at 300 dpi and cropped. Books were kept only when at least 85% of a page's ink fell inside the layer's line boxes, which rejects documents whose text layer is misaligned with the image.

Labels are not human-verified

Transcriptions come from the pre-existing OCR layer, so the systematic errors of that engine are present in this data. Measured against an independently verified benchmark, roughly 40% of lines differ from what two vision-language models read from the same crop, most often where the engine dropped Azerbaijani-specific letters (a for ə, к for ҝ, ч for ҹ).

Train on this; do not evaluate on it. Use LocalDoc/azerbaijani-ocr-benchmark for evaluation — its books are disjoint from this set.

Composition

Cyrillic is a small minority of lines. Sample with reweighting, or measure per-script performance separately, or the recogniser will underfit it.

Normalisation

Unicode NFC, typographic quotes and apostrophes folded to ASCII, soft hyphens removed. Pre-2004 orthography (ən'ənə), end-of-line hyphens and original typos are preserved as printed.