code: def _save_images_bin(self, output_file):
      with open(output_file, "wb") as fid:
          fid.write(struct.pack("L", len(self.images)))
  
          for image_id, image in self.images.items():
              fid.write(struct.pack("I", image_id))
              fid.write(image.q.q.tobytes())
              fid.write(image.tvec.tobytes())
              fid.write(struct.pack("I", image.camera_id))
              fid.write(image.name + "\0")
              fid.write(struct.pack("L", len(image.points2D)))
              data = np.rec.fromarrays(
                  (
                      image.points2D[:, 0],
                      image.points2D[:, 1],
                      image.point3D_ids,
                  )
              )
              fid.write(data.tobytes())
  
imports: from collections import OrderedDict, defaultdict
  from io import StringIO
  from itertools import combinations
  import os
  import struct
  from .camera import Camera
  from .image import Image
  import numpy
  from .rotation import Quaternion
label_desc: Use image node_id 18 for calling the SceneManager obj's underlying member method code with example usage: obj._save_images_bin(output_file) without return types