{
  "frames": [
    {
      "requested_t": -1.5,
      "actual_t": -1.505541257946911
    },
    {
      "requested_t": -1.0,
      "actual_t": -1.005541257946911
    },
    {
      "requested_t": -0.5,
      "actual_t": -0.505541257946911
    },
    {
      "requested_t": 0.0,
      "actual_t": -0.00554125794691096
    },
    {
      "requested_t": 2.0,
      "actual_t": 1.994458742053089
    },
    {
      "requested_t": 3.0,
      "actual_t": 2.9944587420530886
    },
    {
      "requested_t": 4.0,
      "actual_t": 3.9944587420530886
    },
    {
      "requested_t": 5.0,
      "actual_t": 4.994458742053089
    },
    {
      "requested_t": 6.0,
      "actual_t": 5.994458742053089
    }
  ],
  "purpose": "核查道路机动、停止或起步与信号对应，不移动元数据锚点",
  "video_anchor_s": 1.855541257946911,
  "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。"
}