{
  "frames": [
    {
      "requested_t": -4.5,
      "actual_t": -4.5
    },
    {
      "requested_t": -2.5,
      "actual_t": -2.5
    },
    {
      "requested_t": -1.5,
      "actual_t": -1.5
    },
    {
      "requested_t": -0.75,
      "actual_t": -0.75
    },
    {
      "requested_t": -0.25,
      "actual_t": -0.25
    },
    {
      "requested_t": 1.5,
      "actual_t": 1.5
    },
    {
      "requested_t": 3.5,
      "actual_t": 3.5
    },
    {
      "requested_t": 5.5,
      "actual_t": 5.5
    },
    {
      "requested_t": 8.5,
      "actual_t": 8.5
    }
  ],
  "purpose": "复核拥堵车流中白SUV离开正前方、红车接续与本车横向位置变化；雷达有效不等于目标身份不变。",
  "video_anchor_s": 10.0,
  "note": "使用元数据锚点，不按主观场景判断移动视频；不从未标定画面测算距离或推断路权。"
}