Datasets:
license: cc0-1.0
task_categories:
- image-to-text
language:
- bo
tags:
- ocr
- tibetan
- benchmark
- evaluation
pretty_name: BDRC Tibetan OCR Evaluation Benchmark
size_categories:
- n<1K
configs:
- config_name: default
data_files:
- split: test
path: data/test-*.parquet
BDRC Tibetan OCR Benchmark (open subset)
A hand-transcribed benchmark for evaluating Tibetan OCR across writing styles and technologies. This is an open-access set of 472 page images with ground-truth transcriptions and per-page metadata (script, technology, legibility).
Companion to the model BDRC/tibetan-ocr
and the leaderboard
(dozens of OCR systems scored on this benchmark).
The transcriptions were produced by Dharmaduta.
The images were selected through detailed research on Tibetan writing styles in collaboration with Pentsok W. Rtsang who selected and cataloged the images. Most writing styles are represented in the benchmark, except those only present in images that cannot be made fully open access.
Contents & schema
One row per page. We deliberately keep only fully-documentable metadata; the internal fine-grained numeric script id and the 8-class script label are not published here.
| column | description |
|---|---|
image |
the page scan (embedded bytes; anonymized filename) |
transcription |
Tibetan Unicode ground truth (main text box only), botok-normalized |
id |
stable per-page id (the anonymized page number, e.g. 0002) |
technology |
how the page was produced: manuscripts / blockprints / modern / metal_type / typewriter / … |
script |
coarse writing system: Uchen / Ume |
script_4 |
writing-style family: Uchen / Pedri / Gyuyig / Druma / Tsugdri / Danyig / Non-applicable |
period |
palaeographic period of the writing style (e.g. Medieval (15)-present) |
rarity |
how common the writing style is (e.g. 4 - very common) |
legibility |
annotator legibility grade of the page (e.g. 2 - Fair, 4 - Excellent) |
from datasets import load_dataset
ds = load_dataset("BDRC/tibetan-ocr-benchmark", split="test")
Transcription conventions
- Only the main text box is transcribed (no marginalia or pagination).
- Orthographic shorthands are kept as written.
- Placeholders in ground truth:
Iillegible ·Bbroken paper ·Sstruck-through ·D/Kdakini script ·Oornamental. Scribal inserts are marked with().
See transcription_conventions.md and analysis_conventions.md in this repo for
the full manuals.
How CER is computed
Character Error Rate is computed after normalization, both sides:
- Normalize with botok (hypothesis; ground truth is pre-normalized).
- Strip all whitespace.
- Fold repeated tsheg (
U+0F0B) to one. - Remove placeholder characters (
K O B I S). CER = Levenshtein(hyp, ref) / len(ref)(rapidfuzz).
Aggregate CER is an unweighted mean over pages.
License
- CC0-1.0 for the transcriptions and metadata. Image-rights: BDRC claims no copyright over the scans; verifying the underlying works' copyright is the user's responsibility.
Citation
@misc{bdrc_tibetan_ocr_benchmark_2026,
title = {BDRC Tibetan OCR Benchmark},
author = {Buddhist Digital Resource Center},
year = {2026},
howpublished = {Hugging Face},
note = {https://huggingface.co/datasets/BDRC/tibetan-ocr-benchmark}
}
Funded by the Khyentse Foundation ("The BDRC Etext Corpus").