opendatalab/MinerU · error · ValueError

Language not supported. Allowed values

Error message

Language {lang} not supported. Allowed values: {PUBLIC_OCR_LANGUAGES joined by ', '}

What it means

Raised by validate_public_ocr_lang() when an OCR language code passed through MineRU's public API is not in PUBLIC_OCR_LANGUAGES and not one of the Chinese aliases. The public API intentionally exposes a smaller allow-list than the full PaddleOCR language set; inputs are normalized (aliases like 'ch_server'/'chinese' map to 'ch') before the check, so this error means the code is genuinely outside the supported set. The message lists every allowed value.

Solutions

Use one of the values listed in the error message (e.g. 'ch', 'en', and the other PUBLIC_OCR_LANGUAGES entries) — copy the exact code from the message, it enumerates everything allowed.
For Chinese variants use the alias set ('chinese', 'ch_sim', 'ch_server', etc.) which normalize to 'ch'; do not invent new spellings.
If you need a language the public API rejects, check the internal normalization path (normalize_lang, error 151) or open a feature request — do not bypass validation, downstream model loading will fail on unknown keys.

Example fix

# before
result = client.parse(pdf, lang_list=['korean'])

# after
result = client.parse(pdf, lang_list=['ch', 'en'])  # only PUBLIC_OCR_LANGUAGES values

Defensive patterns

Strategy: validation

Validate before calling

from mineru.utils.ocr_language import PUBLIC_OCR_LANGUAGES, validate_public_ocr_lang_list

langs = ['ch', 'en']
assert all(l in PUBLIC_OCR_LANGUAGES or l.lower() in ('chinese', 'ch_sim', 'ch_server') for l in langs)
# or simply let validate_public_ocr_lang_list() run before submitting the job:
langs = validate_public_ocr_lang_list(langs)

Type guard

from typing import TypeGuard

def is_supported_public_lang(lang: object) -> TypeGuard[str]:
    return isinstance(lang, str) and (lang in PUBLIC_OCR_LANGUAGES or lang in _CH_LANG_ALIASES)

Try / catch

try:
    langs = validate_public_ocr_lang_list(request.lang_list)
except ValueError as e:
    return HTTPException(status_code=422, detail=str(e))  # echoes the full allowed list

Prevention

Validate lang_list with validate_public_ocr_lang_list() at the request boundary and return the message verbatim — it lists every legal value.
Expose PUBLIC_OCR_LANGUAGES as the choices in your CLI/OpenAPI schema so invalid values are rejected before MineRU is invoked.
Do not reuse raw PaddleOCR language codes in the public API surface; map them explicitly.

When it happens

Trigger: Calling a public API entry (via validate_public_ocr_lang_list) with e.g. lang='korean', 'jp', 'french', or a typo like 'ch1'/'china' — anything not in PUBLIC_OCR_LANGUAGES and not a registered _CH_LANG_ALIASES entry.

Common situations: Porting code from the internal API that accepts raw PaddleOCR lang codes (like 'korean' or 'japan') to the public API which does not; guessing language codes ('en-US', 'CH', 'zh') instead of using the documented values; passing the display name ('Chinese') rather than the code.

Related errors

AI-assisted analysis of opendatalab/MinerU@4fe4bde114 (2026-08-14). Data as JSON: /api/errors/61109748523be429. Report an issue: GitHub.

Appendix: source

Thrown at mineru/utils/ocr_language.py:121

def format_public_ocr_lang_description() -> str:
    """生成公开 API 使用的 OCR 语言说明，避免入口文案各自维护。"""
    option_lines = [
        f"- {lang}: {_PUBLIC_OCR_LANGUAGE_DESCRIPTIONS[lang]}."
        for lang in PUBLIC_OCR_LANGUAGES
    ]
    return (
        "(Adapted for pipeline backend only) Input the languages in the pdf "
        "to improve OCR accuracy. Options:\n"
        + "\n".join(option_lines)
    )


def validate_public_ocr_lang(lang: str) -> str:
    """校验公开入口允许的 OCR 语言，并将兼容入口规范到实际模型 key。"""
    if lang in _CH_LANG_ALIASES:
        return "ch"
    if lang not in PUBLIC_OCR_LANGUAGES:
        raise ValueError(
            f"Language {lang} not supported. Allowed values: "
            + ", ".join(PUBLIC_OCR_LANGUAGES)
        )
    return lang


def validate_public_ocr_lang_list(lang_list: list[str]) -> list[str]:
    """校验公开 API 的语言列表，返回可安全传入下游的副本。"""
    effective_lang_list = lang_list or ["ch"]
    return [validate_public_ocr_lang(lang) for lang in effective_lang_list]


def normalize_ocr_model_lang(
    lang: str | None,
    *,
    device: str | None = None,
    supported_langs=None,
) -> str:

View on GitHub (pinned to 4fe4bde114)