Few Questions regarding usage of Cyclegan

[sparshgarg23]

First of all thank you for opensourcing this project.I have some queries and I hope you will be able to help me in resolving them.
1.I was experimenting with the colab tutorial and it seems that during the training the following stack trace was reported

Traceback (most recent call last):
  File "/usr/local/lib/python3.7/dist-packages/urllib3/connection.py", line 159, in _new_conn
    (self._dns_host, self.port), self.timeout, **extra_kw)
  File "/usr/local/lib/python3.7/dist-packages/urllib3/util/connection.py", line 80, in create_connection
    raise err
  File "/usr/local/lib/python3.7/dist-packages/urllib3/util/connection.py", line 70, in create_connection
    sock.connect(sa)
ConnectionRefusedError: [Errno 111] Connection refused

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/lib/python3.7/dist-packages/urllib3/connectionpool.py", line 600, in urlopen
    chunked=chunked)
  File "/usr/local/lib/python3.7/dist-packages/urllib3/connectionpool.py", line 354, in _make_request
    conn.request(method, url, **httplib_request_kw)
  File "/usr/lib/python3.7/http/client.py", line 1281, in request
    self._send_request(method, url, body, headers, encode_chunked)
  File "/usr/lib/python3.7/http/client.py", line 1327, in _send_request
    self.endheaders(body, encode_chunked=encode_chunked)
  File "/usr/lib/python3.7/http/client.py", line 1276, in endheaders
    self._send_output(message_body, encode_chunked=encode_chunked)
  File "/usr/lib/python3.7/http/client.py", line 1036, in _send_output
    self.send(msg)
  File "/usr/lib/python3.7/http/client.py", line 976, in send
    self.connect()
  File "/usr/local/lib/python3.7/dist-packages/urllib3/connection.py", line 181, in connect
    conn = self._new_conn()
  File "/usr/local/lib/python3.7/dist-packages/urllib3/connection.py", line 168, in _new_conn
    self, "Failed to establish a new connection: %s" % e)
urllib3.exceptions.NewConnectionError: <urllib3.connection.HTTPConnection object at 0x7ff679139850>: Failed to establish a new connection: [Errno 111] Connection refused

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/lib/python3.7/dist-packages/requests/adapters.py", line 449, in send
    timeout=timeout
  File "/usr/local/lib/python3.7/dist-packages/urllib3/connectionpool.py", line 638, in urlopen
    _stacktrace=sys.exc_info()[2])
  File "/usr/local/lib/python3.7/dist-packages/urllib3/util/retry.py", line 399, in increment
    raise MaxRetryError(_pool, url, error or ResponseError(cause))
urllib3.exceptions.MaxRetryError: HTTPConnectionPool(host='localhost', port=8097): Max retries exceeded with url: /env/main (Caused by NewConnectionError('<urllib3.connection.HTTPConnection object at 0x7ff679139850>: Failed to establish a new connection: [Errno 111] Connection refused'))

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/lib/python3.7/dist-packages/visdom/__init__.py", line 711, in _send
    data=json.dumps(msg),
  File "/usr/local/lib/python3.7/dist-packages/visdom/__init__.py", line 677, in _handle_post
    r = self.session.post(url, data=data)
  File "/usr/local/lib/python3.7/dist-packages/requests/sessions.py", line 578, in post
    return self.request('POST', url, data=data, json=json, **kwargs)
  File "/usr/local/lib/python3.7/dist-packages/requests/sessions.py", line 530, in request
    resp = self.send(prep, **send_kwargs)
  File "/usr/local/lib/python3.7/dist-packages/requests/sessions.py", line 643, in send
    r = adapter.send(request, **kwargs)
  File "/usr/local/lib/python3.7/dist-packages/requests/adapters.py", line 516, in send
    raise ConnectionError(e, request=request)
requests.exceptions.ConnectionError: HTTPConnectionPool(host='localhost', port=8097): Max retries exceeded with url: /env/main (Caused by NewConnectionError('<urllib3.connection.HTTPConnection object at 0x7ff679139850>: Failed to establish a new connection: [Errno 111] Connection refused'))
[Errno 99] Cannot assign requested address
on_close() takes 1 positional argument but 3 were given
[Errno 99] Cannot assign requested address
on_close() takes 1 positional argument but 3 were given
[Errno 99] Cannot assign requested address
on_close() takes 1 positional argument but 3 were given
Visdom python client failed to establish socket to get messages from the server. This feature is optional and can be disabled by initializing Visdom with `use_incoming_socket=False`, which will prevent waiting for this request to timeout.


Could not connect to Visdom server. 
 Trying to start a server....
Command: /usr/bin/python3 -m visdom.server -p 8097 &>/dev/null &
wandb: (1) Create a W&B account
wandb: (2) Use an existing W&B account
wandb: (3) Don't visualize my results
wandb: Enter your choice: [Errno 99] Cannot assign requested address
on_close() takes 1 positional argument but 3 were given
[Errno 99] Cannot assign requested address
on_close() takes 1 positional argument but 3 were given

I am assuming that wandb here is similar to tensorboard's logging .Plus isn't visdom incompatible with colab?

Question 2
I am interested in using cyclegan to perform image translation on the following tasks
GTA/Synthia to cityscape
VKitti to real kitti
But since GTA contains at most 22000 images and cityscapes contains apprx 5000 images.Wouldn't there be an imbalance between the two datasets.

so the training script will be like this

python train.py --dataroot path to gta2cityscape dataset model=one_direction_test phase=train loadSize=1024 fineSize=1024 resize_or_crop="scale_width_and_crop"

Dataset Organization

 data
│   ├── cityscapes
│   │   ├── leftImg8bit
│   │   │   ├── train
│   │   │   ├── val
│   │   ├── gtFine
│   │   │   ├── train
│   │   │   ├── val
│   ├── gta
│   │   ├── images
│   │   ├── labels

Let me know if my understanding of reproducing the result for GTA2Cityscape is correct.Also if possible any help in resolving query 1 will be helpful.Looking at colab,it seems the training process is stuck

[sparshgarg23]

@junyanz I was able to get the training process initiated.At epoch 67 the current translation for zebra2horse looks like this.
Any reason why the results are coming out to be like this
zebra->horse