{
  "method": "manual frame review after coarse and 1-second contact-sheet scans, followed by local Qwen3.5:9b source-frame re-audit for duplicate, conflict, and newly recovered cases",
  "definition": "first clear frame in which Yousuke Yukimatsu is visibly shirtless; the physical removal may be off-camera",
  "population_rule": "YouTube videos with duration >= 900 seconds; short clips excluded",
  "analyzed_long_sets": 23,
  "confirmed": 13,
  "not_observed": 4,
  "inconclusive": 6,
  "statistics_confirmed_only": {
    "mean_seconds": 1065.2,
    "mean_mmss": "17:45.2",
    "median_seconds": 900.0,
    "median_mmss": "15:00",
    "mean_set_position_percent": 29.0932,
    "median_set_position_percent": 22.7959,
    "range_seconds": [
      0.0,
      2755.0
    ],
    "inclusion_note": "Keep Hush Live is an upper-bound first-observed time because the first checked source frame was already shirtless; this can pull the mean later than the physical transition."
  },
  "records": [
    {
      "id": "zf34HLtILKY",
      "title": "CTM Festival Berlin 2025",
      "duration_seconds": 7110,
      "first_clear_shirtless_seconds": 1415,
      "status": "confirmed",
      "precision_seconds": 5
    },
    {
      "id": "EIvt_WrrxW0",
      "title": "DEF TV",
      "duration_seconds": 5931,
      "first_clear_shirtless_seconds": 1050,
      "status": "confirmed",
      "precision_seconds": 5
    },
    {
      "id": "CxflYGeSx7Q",
      "title": "Boiler Room Tokyo x Super Dommune",
      "duration_seconds": 5611,
      "first_clear_shirtless_seconds": null,
      "status": "inconclusive",
      "precision_seconds": null,
      "note": "Local Qwen source frames show the performer shirted through 1200 s and shirtless by 4200 s; the transition window was not recovered, so the old 870 s value is removed.",
      "observation_basis": "local_qwen_decoded_source_frames"
    },
    {
      "id": "ezaZ2zOkAW4",
      "title": "AURA Sofia Bulgaria 2026",
      "duration_seconds": 4987,
      "first_clear_shirtless_seconds": null,
      "status": "inconclusive",
      "note": "coarse scan did not provide an unambiguous view of Yousuke; screen imagery and performer view conflict"
    },
    {
      "id": "LuCzsPYrxYs",
      "title": "Lollapalooza Chile 2026",
      "duration_seconds": 4553,
      "first_clear_shirtless_seconds": 705,
      "status": "confirmed",
      "precision_seconds": 5,
      "note": "Existing 705 s value retained; local Qwen decoded-source windows confirm shirtless state at approximately 704.5 s, while a later 2550 s window is already shirtless.",
      "observation_basis": "local_qwen_decoded_source_frames"
    },
    {
      "id": "T1tcUfUhR5U",
      "title": "Boiler Room Tokyo",
      "duration_seconds": 3595.377778,
      "first_clear_shirtless_seconds": 819.6,
      "status": "confirmed",
      "precision_seconds": 1
    },
    {
      "id": "E7jzrBuFBpA",
      "title": "TheLotRadio 09-10-2025",
      "duration_seconds": 3469,
      "first_clear_shirtless_seconds": 2755,
      "status": "confirmed",
      "note": "Local Qwen decoded-source frames show the first clear shirtless sample at approximately 2754.5 s in the 2700–2800 s verification window.",
      "precision_seconds": 10,
      "observation_kind": "first_clear_source_frame_sample",
      "observation_basis": "local_qwen_decoded_source_frames"
    },
    {
      "id": "UoxUFOYcez0",
      "title": "Ultra Music Festival Miami 2026",
      "duration_seconds": 3469,
      "first_clear_shirtless_seconds": 785,
      "status": "confirmed",
      "precision_seconds": 5
    },
    {
      "id": "ALN8YdAHN5w",
      "title": "BitterSweet Festival 2025",
      "duration_seconds": 3339,
      "first_clear_shirtless_seconds": null,
      "status": "not_observed",
      "note": "stage/crowd framing did not provide an unambiguous confirmation"
    },
    {
      "id": "IP9v-2nEA2E",
      "title": "Coachella 2026 Weekend 2",
      "duration_seconds": 3318,
      "first_clear_shirtless_seconds": 830,
      "status": "confirmed",
      "precision_seconds": 5
    },
    {
      "id": "qhqGGCbQEuI",
      "title": "HÖR Berlin Sep 20 2023",
      "duration_seconds": 3283,
      "first_clear_shirtless_seconds": 1389,
      "status": "confirmed",
      "precision_seconds": 1
    },
    {
      "id": "uzWj241wjvA",
      "title": "Coachella 2026 Weekend 1",
      "duration_seconds": 3268,
      "first_clear_shirtless_seconds": 620,
      "status": "confirmed",
      "precision_seconds": 5
    },
    {
      "id": "WvyvwlowHWM",
      "title": "HÖR Berlin Nov 19 2022",
      "duration_seconds": 3258,
      "first_clear_shirtless_seconds": 1409,
      "status": "confirmed",
      "precision_seconds": 1
    },
    {
      "id": "5K65xwSXlUw",
      "title": "Keep Hush Live",
      "duration_seconds": 3221,
      "first_clear_shirtless_seconds": 900,
      "status": "confirmed",
      "note": "Local Qwen decoded-source frames are already clearly shirtless at the first checked frame (900 s); the physical transition may be earlier.",
      "precision_seconds": 100,
      "observation_kind": "first_observed_upper_bound",
      "observation_basis": "local_qwen_decoded_source_frames"
    },
    {
      "id": "6khzv8R8gi4",
      "title": "OneUniverse Festival 2026",
      "duration_seconds": 3155,
      "first_clear_shirtless_seconds": null,
      "status": "inconclusive",
      "note": "very dark festival footage; performer cannot be reliably identified"
    },
    {
      "id": "yzaZHb9SP3k",
      "title": "Outside Lands 2026",
      "duration_seconds": 2734,
      "first_clear_shirtless_seconds": 1170,
      "status": "confirmed",
      "precision_seconds": 5
    },
    {
      "id": "ueyHaBHvUdQ",
      "title": "Limassol Cyprus 2025",
      "duration_seconds": 2090,
      "first_clear_shirtless_seconds": null,
      "status": "not_observed",
      "note": "full coarse review; no clear shirtless frame"
    },
    {
      "id": "mU7821DXt7Y",
      "title": "LIVE EXIT 2025",
      "duration_seconds": 1218,
      "first_clear_shirtless_seconds": null,
      "status": "not_observed",
      "note": "available cut is crowd/stage-heavy; no clear confirmation"
    },
    {
      "id": "NSFxajndRcQ",
      "title": "EDC Mexico 2026",
      "duration_seconds": 1214,
      "first_clear_shirtless_seconds": null,
      "status": "inconclusive",
      "note": "Storyboard Qwen produced a candidate near 192 s, but source-frame verification was blocked by HTTP 403; no exact time is published.",
      "observation_basis": "local_qwen_storyboard_candidate_source_unverified"
    },
    {
      "id": "fgtRMwxLdFo",
      "title": "Atlanta Debut 2025",
      "duration_seconds": 1125,
      "first_clear_shirtless_seconds": null,
      "status": "not_observed",
      "note": "full coarse review; crowd/stage framing did not show a clear shirtless frame"
    },
    {
      "id": "TG8nZ9p-Mf0",
      "title": "Yousuke Yukimatsu x BRDG 2020",
      "duration_seconds": 994,
      "first_clear_shirtless_seconds": null,
      "status": "inconclusive",
      "precision_seconds": null,
      "note": "Local Qwen decoded-source frames from 0–180 s are too dark and obstructed to observe the performer; the old 30 s value is not retained without later coverage.",
      "observation_basis": "local_qwen_decoded_source_frames"
    },
    {
      "id": "brFcf6sXY6A",
      "title": "Dallas 2026",
      "duration_seconds": 1424,
      "first_clear_shirtless_seconds": 0,
      "status": "confirmed",
      "precision_seconds": 1,
      "note": "already visibly shirtless in the first clear frame"
    },
    {
      "id": "nriNdf862F4",
      "title": "Roskilde Festival 2026",
      "duration_seconds": 1409,
      "first_clear_shirtless_seconds": null,
      "status": "inconclusive",
      "note": "dark crowd/stage-heavy cut; no reliable performer-body view"
    }
  ],
  "reanalysis": {
    "model": "qwen3.5:9b",
    "runtime": "local Ollama vision mode on Mac",
    "scope": "23 retained videos for the storyboard pass; source-frame verification on six high-risk cases",
    "source_frame_verification": [
      {
        "id": "LuCzsPYrxYs",
        "result": "supports existing value",
        "observed_seconds": 704.5
      },
      {
        "id": "5K65xwSXlUw",
        "result": "already shirtless at first checked frame",
        "observed_seconds": 900
      },
      {
        "id": "E7jzrBuFBpA",
        "result": "shirtless in transition window",
        "observed_seconds": 2754.5
      },
      {
        "id": "CxflYGeSx7Q",
        "result": "shirted through 1200 s; shirtless by 4200 s; transition unresolved"
      },
      {
        "id": "TG8nZ9p-Mf0",
        "result": "performer not observable in checked 0–180 s window"
      },
      {
        "id": "NSFxajndRcQ",
        "result": "source verification blocked by HTTP 403"
      }
    ]
  }
}