def get_model_file(name, root='./pretrain_models'):
r"""Return location for the pretrained on local file system.
This function will download from online model zoo when model cannot be found or has mismatch.
The root directory will be created if it doesn't exist.
Parameters
----------
name : str
Name of the model.
root : str, default './pretrain_models'
Location for keeping the model parameters.
Returns
-------
file_path
Path to the requested pretrained model file.
"""
file_name = '{name}-{short_hash}'.format(name=name,
short_hash=short_hash(name))
root = os.path.expanduser(root)
file_path = os.path.join(root, file_name + '.pth')
sha1_hash = _model_sha1[name]
if os.path.exists(file_path):
if check_sha1(file_path, sha1_hash):
return file_path
else:
print(
'Mismatch in the content of model file detected. Downloading again.'
)
else:
print('Model file is not found. Downloading.')
if not os.path.exists(root):
os.makedirs(root)
zip_file_path = os.path.join(root, file_name + '.zip')
repo_url = os.environ.get('ENCODING_REPO', encoding_repo_url)
if repo_url[-1] != '/':
repo_url = repo_url + '/'
download(_url_format.format(repo_url=repo_url, file_name=file_name),
path=zip_file_path,
overwrite=True)
with zipfile.ZipFile(zip_file_path) as zf:
zf.extractall(root)
os.remove(zip_file_path)
if check_sha1(file_path, sha1_hash):
return file_path
else:
raise ValueError(
'Downloaded file has different hash. Please try again.')
def download_city(path, overwrite=False):
_CITY_DOWNLOAD_URLS = [('gtFine_trainvaltest.zip',
'99f532cb1af174f5fcc4c5bc8feea8c66246ddbc'),
('leftImg8bit_trainvaltest.zip',
'2c0b77ce9933cc635adda307fbba5566f5d9d404')]
download_dir = os.path.join(path, 'downloads')
mkdir(download_dir)
for filename, checksum in _CITY_DOWNLOAD_URLS:
if not check_sha1(filename, checksum):
raise UserWarning('File {} is downloaded but the content hash does not match. ' \
'The repo may be outdated or download may be incomplete. ' \
'If the "repo_url" is overridden, consider switching to ' \
'the default repo.'.format(filename))
# extract
with zipfile.ZipFile(filename, "r") as zip_ref:
zip_ref.extractall(path=path)
print("Extracted", filename)
def check_file(filename, checksum, sha1):
if not os.path.exists(filename):
raise ValueError('File not found: ' + filename)
if checksum and not check_sha1(filename, sha1):
raise ValueError('Corrupted file: ' + filename)