{
  "benchmark": "LiveLingo Real-Time Voice Translation Benchmark 2026",
  "version": "1.0",
  "published": "2026-06-04",
  "metrics": {
    "TTF": {
      "name": "Final Transcript Latency",
      "unit": "ms",
      "definition": "Wall-clock time from speaker end-of-speech (energy-VAD, 500ms silence) to first is_final translation emit.",
      "per_system": {
        "livelingo": {
          "n_utterances": 27,
          "ttf_median_ms": 1518,
          "ttf_ci_lo_ms": 1096,
          "ttf_ci_hi_ms": 1852,
          "ttf_min_ms": 13,
          "ttf_max_ms": 3818
        },
        "google_cloud": {
          "n_utterances": 30,
          "ttf_median_ms": 26736,
          "ttf_ci_lo_ms": 20296,
          "ttf_ci_hi_ms": 51586,
          "ttf_min_ms": 796,
          "ttf_max_ms": 74326
        },
        "azure": {
          "n_utterances": 30,
          "ttf_median_ms": 4755,
          "ttf_ci_lo_ms": 3620,
          "ttf_ci_hi_ms": 9507,
          "ttf_min_ms": 282,
          "ttf_max_ms": 27162
        },
        "whisper_gpt": {
          "n_utterances": 28,
          "ttf_median_ms": 2720,
          "ttf_ci_lo_ms": 1880,
          "ttf_ci_hi_ms": 3396,
          "ttf_min_ms": 249,
          "ttf_max_ms": 8795
        }
      }
    }
  },
  "clips": [
    {
      "id": "voa-zh-001-biden-xi-summit",
      "src": "zh",
      "tgt": "en",
      "youtube_id": "cWEhvlRQBkE",
      "start_s": 90,
      "end_s": 210,
      "duration_s": 120,
      "license": "public-domain (VOA, US fed gov work)"
    },
    {
      "id": "voa-es-002-venezuela-migration",
      "src": "es",
      "tgt": "en",
      "youtube_id": "6Wn5sjiAAoU",
      "start_s": 0,
      "end_s": 120,
      "duration_s": 120,
      "license": "public-domain"
    },
    {
      "id": "voa-pt-001-costa-junior-angola",
      "src": "pt",
      "tgt": "en",
      "youtube_id": "4P3wYdmKWQI",
      "start_s": 30,
      "end_s": 150,
      "duration_s": 120,
      "license": "public-domain"
    }
  ],
  "methodology_url": "https://www.livelingo.io/research/benchmark-2026#methodology",
  "page_url": "https://www.livelingo.io/research/benchmark-2026",
  "license": "CC-BY-4.0"
}