{
  "requested_second": 154,
  "exact_baseline_frame": {
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    "timestamp_seconds": 154.0,
    "source_pts_seconds": 154.0,
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    "height": 720,
    "selection_reasons": [
      "baseline_1fps_or_last"
    ],
    "source_width": 720,
    "source_height": 1280,
    "image_url": "https://ai-video-relay-check-20261027.pages.dev/frames/frame-00004620.webp"
  },
  "nearby_frames": [
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    },
    {
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      "source_pts_seconds": 154.0,
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      ],
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      "source_height": 1280,
      "image_url": "https://ai-video-relay-check-20261027.pages.dev/frames/frame-00004620.webp"
    },
    {
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      "timestamp_seconds": 154.03333333333333,
      "source_pts_seconds": 154.03333333333333,
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      "width": 405,
      "height": 720,
      "selection_reasons": [
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      ],
      "source_width": 720,
      "source_height": 1280,
      "image_url": "https://ai-video-relay-check-20261027.pages.dev/frames/frame-00004621.webp"
    },
    {
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      "timestamp_seconds": 154.06666666666666,
      "source_pts_seconds": 154.06666666666666,
      "timestamp": "154.066667",
      "reasons": [
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        "scene_context"
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      "image": "https://ai-video-relay-check-20261027.pages.dev/frames/frame-00004622.webp",
      "width": 405,
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      "selection_reasons": [
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      "source_height": 1280,
      "image_url": "https://ai-video-relay-check-20261027.pages.dev/frames/frame-00004622.webp"
    },
    {
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      "source_frame_index": 4626,
      "timestamp_seconds": 154.2,
      "source_pts_seconds": 154.2,
      "timestamp": "154.200000",
      "reasons": [
        "motion_dense"
      ],
      "image": "https://ai-video-relay-check-20261027.pages.dev/frames/frame-00004626.webp",
      "width": 405,
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      "selection_reasons": [
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      "source_height": 1280,
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    }
  ],
  "screen_observation": {
    "time": 154.0,
    "source_frame_index": 4620,
    "raw_ocr": "",
    "raw_caption": "",
    "raw_title": "",
    "screen_caption": "",
    "screen_title": "",
    "reviewed_changes": [],
    "verification": "automatic OCR; not independently verified",
    "timing": "observed frame time; onset/offset not known to subsecond precision",
    "is_confirmed_speech": false
  },
  "raw_ASR_at_estimated_time": [],
  "content_section": {
    "index": 20,
    "start": 153.3,
    "end": 154.066667,
    "title": "彩条过渡",
    "visual_observation": "多色测试条。",
    "camera": "剪辑过渡。",
    "uncertainty": "",
    "provenance": "assistant visual review of source-frame sheets; not an independent human or automatic semantic-model benchmark"
  },
  "unknowns": [
    "ASR not a verified listening transcript",
    "Caption display time can differ from speech time",
    "Assistant observation must be cross-checked by actually opening image"
  ]
}