class_docstr: Data loader for videos.
class_docstr_tok: ["Data","loader","for","videos","."]
code: def camera_ext(self):
      if self.camera_type == "json":
          return ".json"
  
      raise ValueError(f"Unknown camera_type {self.camera_type}")
  
imports: import json
  from typing import List, Tuple
  from absl import logging
  import cv2
  import numpy
  from nerfies import gpath
  from nerfies import types
  from nerfies import utils
  from nerfies.datasets import core
label_desc: Use image node_id 4 for calling the NerfiesDataSource obj's underlying member method code with example usage: obj.camera_ext() and returns: str