Problem with 'Unknown image file format' error for GCS image in Tensorflow style transfer demo

Question

I'm wanting to use my own images for this Tensorflow Style Transfer demo, which I've copied to my own Colab notebook.

[https://www.tensorflow.org/hub/tutorials/tf2_arbitrary_image_stylization][1]

I have images stored in a GCS bucket but have been getting image format errors. To test this, I took one of the images from the Tensorflow demo, downloaded it and put it in my GCS bucket, added the link to the "Let's try it on more images" section of my demo code, and am getting the same file format error message I was previously getting with my own images.

Here's where I've inserted the GCS version of the image:

content_urls = dict(
  tueblingen02='https://storage.cloud.google.com/01_bucket-02/Tuebingen_Neckarfront-vox.jpeg',
  sea_turtle='https://upload.wikimedia.org/wikipedia/commons/d/d7/Green_Sea_Turtle_grazing_seagrass.jpg',
  tuebingen='https://upload.wikimedia.org/wikipedia/commons/0/00/Tuebingen_Neckarfront.jpg',
  grace_hopper='https://storage.googleapis.com/download.tensorflow.org/example_images/grace_hopper.jpg',
  )
style_urls = dict(
  kanagawa_great_wave='https://upload.wikimedia.org/wikipedia/commons/0/0a/The_Great_Wave_off_Kanagawa.jpg',
  kandinsky_composition_7='https://upload.wikimedia.org/wikipedia/commons/b/b4/Vassily_Kandinsky%2C_1913_-_Composition_7.jpg',

etc ...

The resulting error message:

InvalidArgumentError: Unknown image file format. One of JPEG, PNG, GIF, BMP required. [Op:DecodeImage]

Full message:

---------------------------------------------------------------------------
InvalidArgumentError                      Traceback (most recent call last)
<ipython-input-16-3ded16359898> in <module>()
     26 content_image_size = 384
     27 style_image_size = 256
---> 28 content_images = {k: load_image(v, (content_image_size, content_image_size)) for k, v in content_urls.items()}
     29 style_images = {k: load_image(v, (style_image_size, style_image_size)) for k, v in style_urls.items()}
     30 style_images = {k: tf.nn.avg_pool(style_image, ksize=[3,3], strides=[1,1], padding='SAME') for k, style_image in style_images.items()}

3 frames
<ipython-input-16-3ded16359898> in <dictcomp>(.0)
     26 content_image_size = 384
     27 style_image_size = 256
---> 28 content_images = {k: load_image(v, (content_image_size, content_image_size)) for k, v in content_urls.items()}
     29 style_images = {k: load_image(v, (style_image_size, style_image_size)) for k, v in style_urls.items()}
     30 style_images = {k: tf.nn.avg_pool(style_image, ksize=[3,3], strides=[1,1], padding='SAME') for k, style_image in style_images.items()}

<ipython-input-2-1485a3082999> in load_image(image_url, image_size, preserve_aspect_ratio)
     19   img = tf.io.decode_image(
     20       tf.io.read_file(image_path),
---> 21       channels=3, dtype=tf.float32)[tf.newaxis, ...]
     22   img = crop_center(img)
     23   img = tf.image.resize(img, image_size, preserve_aspect_ratio=True)

/usr/local/lib/python3.7/dist-packages/tensorflow/python/util/traceback_utils.py in error_handler(*args, **kwargs)
    151     except Exception as e:
    152       filtered_tb = _process_traceback_frames(e.__traceback__)
--> 153       raise e.with_traceback(filtered_tb) from None
    154     finally:
    155       del filtered_tb

/usr/local/lib/python3.7/dist-packages/tensorflow/python/framework/ops.py in raise_from_not_ok_status(e, name)
   7184 def raise_from_not_ok_status(e, name):
   7185   e.message += (" name: " + name if name is not None else "")
-> 7186   raise core._status_to_exception(e) from None  # pylint: disable=protected-access
   7187 
   7188 

InvalidArgumentError: Unknown image file format. One of JPEG, PNG, GIF, BMP required. [Op:DecodeImage]

So that's confusing me because the image works fine when it's hosted elsewhere, leading me to believe it's not an image format issue, but something else.

I'd greatly appreciate any input or suggestions on what might be happening here. thx