{
  "schema_version": 2,
  "benchmark": "Speakmac vs Wispr Flow 27-clip licensed real-speech benchmark corpus",
  "benchmark_date": "2026-07-28",
  "corpus_version": "2026-07-28-real-speech-v1",
  "selection": {
    "svarah": "18 deterministic spread offsets; first eligible 3.0-10.5 second, 7-22 word row",
    "librispeech": "9 deterministic offsets; first eligible 7-22 word row from a new speaker"
  },
  "normalization": {
    "change_notice": "Source audio was resampled and loudness-normalized for this benchmark.",
    "ffmpeg_filter": "loudnorm=I=-20:TP=-2:LRA=7",
    "sample_rate_hz": 16000,
    "channels": 1,
    "codec": "pcm_s16le"
  },
  "sources": {
    "svarah": {
      "title": "Svarah: Evaluating English ASR Systems on Indian Accents",
      "creators": [
        "Tahir Javed",
        "Sakshi Joshi",
        "Vignesh Nagarajan",
        "Sai Sundaresan",
        "Janki Nawale",
        "Abhigyan Raman",
        "Kaushal Santosh Bhogale",
        "Pratyush Kumar",
        "Mitesh M. Khapra"
      ],
      "official_url": "https://huggingface.co/datasets/ai4bharat/Svarah",
      "acquisition_url": "https://huggingface.co/datasets/amrithanandini/svarah",
      "license": "CC BY 4.0",
      "license_url": "https://creativecommons.org/licenses/by/4.0/",
      "attribution_note": "18 normalized derivatives from the Svarah test material. No endorsement is implied.",
      "provenance_limit": "The historical corpus acquired these fixed rows through the listed public mirror. The official repository license was rechecked on 2026-08-31; official row-level access remained gated, so mirror-to-official bit identity was not independently rechecked."
    },
    "librispeech": {
      "title": "LibriSpeech: an ASR corpus based on public domain audio books",
      "creators": [
        "Vassil Panayotov",
        "Guoguo Chen",
        "Daniel Povey",
        "Sanjeev Khudanpur"
      ],
      "official_url": "https://www.openslr.org/12",
      "acquisition_url": "https://huggingface.co/datasets/openslr/librispeech_asr",
      "license": "CC BY 4.0",
      "license_url": "https://creativecommons.org/licenses/by/4.0/",
      "attribution_note": "9 normalized derivatives from LibriSpeech test-clean. No endorsement is implied."
    }
  },
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