audio_dataset_curation/README.md

Audio Dataset Curation

Curate high-quality speech clips from the Common Voice dataset by validating duration, audio format, and language tags.

What this example shows

• Loading multimodal audio datasets with @hf_dataset_asset
• Validating audio objects: checking array structure and duration ranges
• Filtering by language locale tags
• Quantifying dataset retention through materialization metadata
• Processing audio fields with nested dict structures (audio["array"], audio["duration"])

Dataset

mozilla-foundation/common_voice_11_0 (English split) — 240K+ crowdsourced speech recordings across diverse speakers, ages, accents, and recording conditions. High-quality audio resource for training speech recognition and speech-to-text models.

Metric	Value
Language	English (en)
Total clips	~240K
Duration range	2–6 seconds (typical)
Audio format	PCM, 48kHz

Curation rules

Rule	Threshold	Reason
Duration	1–20 seconds	Filter too-short (noise) and too-long (out-of-spec) clips
Audio array	Must exist and be non-null	Reject corrupted/malformed samples
Language tag	Must start with en	English-only filtering

Key API

@hf_dataset_asset(
    path="mozilla-foundation/common_voice_11_0",
    config="en",
    split="train",
)
def curated_audio_dataset(context, dataset: Dataset) -> MaterializeResult:
    def is_valid(example):
        audio = example.get("audio")
        if audio is None or "array" not in audio:
            return False
        if audio.get("duration", 0) < MIN_DURATION or > MAX_DURATION:
            return False
        return example.get("locale", "").startswith("en")

    curated = dataset.filter(is_valid)
    return MaterializeResult(value=curated, metadata={
        "original_rows": len(dataset),
        "curated_rows": len(curated),
        "retention_pct": round(100 * len(curated) / len(dataset), 1),
    })

Metadata returned

Key	Description
original_rows	Row count before filtering
curated_rows	Row count after filtering
removed_rows	Count of invalid samples dropped
dataset	Source dataset identifier
fingerprint	Reproducibility hash from the datasets library

Storage layout

.dagster_hf_storage/
└── curated_audio_dataset/     # Arrow format via save_to_disk()

How to run

cd dagster_hf_datasets_examples

dagster dev -m audio_dataset_curation.definitions

Then navigate to the Asset Catalog in the Dagster UI (http://localhost:3000) and materialize curated_audio_dataset.