detect_landmark.py

#!/usr/bin/python

# Copyright 2016 Google, Inc
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

"""Identifies the landmark for the given image."""

import argparse

from googleapiclient import discovery
import httplib2
from oauth2client.client import GoogleCredentials


# [START get_vision_service]
# The url template to retrieve the discovery document for trusted testers.
DISCOVERY_URL='https://{api}.googleapis.com/$discovery/rest?version={apiVersion}'


def get_vision_service():
    credentials = GoogleCredentials.get_application_default()
    return discovery.build('vision', 'v1', credentials=credentials,
                           discoveryServiceUrl=DISCOVERY_URL)
# [END get_vision_service]


# [START identify_landmark]
def identify_landmark(gcs_uri, max_results=4):
    """Uses the Vision API to identify the landmark in the given image.

    Args:
        gcs_uri: A uri of the form: gs://bucket/object

    Returns:
        An array of dicts with information about the landmarks in the picture.
    """
    batch_request = [{
        'image': {
            'source': {
                'gcs_image_uri': gcs_uri
            }
        },
        'features': [{
            'type': 'LANDMARK_DETECTION',
            'maxResults': max_results,
            }]
        }]

    service = get_vision_service()
    request = service.images().annotate(body={
        'requests': batch_request,
        })
    response = request.execute()

    return response['responses'][0].get('landmarkAnnotations', None)
# [END identify_landmark]


# [START main]
def main(gcs_uri):
    if gcs_uri[:5] != 'gs://':
        raise Exception('Image uri must be of the form gs://bucket/object')
    annotations = identify_landmark(gcs_uri)
    if not annotations:
        print('No landmark identified')
    else:
        print('\n'.join(a['description'] for a in annotations))
# [END main]


if __name__ == '__main__':
    parser = argparse.ArgumentParser(
        description='Identifies the landmark in the given image.')
    parser.add_argument(
        'gcs_uri', help=('The Google Cloud Storage uri to the image to identify'
                         ', of the form: gs://bucket_name/object_name.jpg'))
    args = parser.parse_args()

    main(args.gcs_uri)