{
  "pack": {
    "type": "tuple",
    "items": [
      {
        "type": "tensor_from_image",
        "image": "image1",
        "transforms": [
          {
            "type": "image_to_image",
            "name": "center_crop",
            "width": "$width",
            "height": "$height"
          },
          {
            "type": "image_to_image",
            "name": "scale",
            "width": "$width",
            "height": "$height"
          },
          {
            "type": "image_to_tensor",
            "name": "rgb_norm",
            "mean": [
              0.0,
              0.0,
              0.0
            ],
            "std": [
              1.0,
              1.0,
              1.0
            ]
          }
        ]
      },
      {
        "type": "tensor",
        "dtype": "float",
        "sizes": [
          1,
          3
        ],
        "items": [
          "$width",
          "$height",
          "$scale"
        ]
      },
      {
        "type": "tensor",
        "dtype": "float",
        "sizes": [
          1
        ],
        "items": [
          "$should_run_track"
        ]
      },
      {
        "type": "tensor",
        "dtype": "float",
        "sizes": [
          "$rois_n",
          4
        ],
        "items": "$rois"
      }
    ]
  },
  "unpack": {
    "type": "tuple",
    "items": [
      {
        "type": "tensor",
        "key": "image1",
        "dtype": "float"
      },
      {
        "type": "tensor",
        "key": "image_info",
        "dtype": "float"
      },
      {
        "type": "tensor",
        "key": "should_run_track",
        "dtype": "float"
      },
      {
        "type": "tensor",
        "key": "previous_rois",
        "dtype": "float"
      }
    ]
  }
}