You can follow along with the code in the Jupyter notebook ch-12a_VGG16_TensorFlow.
For all examples of VGG16 in TensorFlow, we first download the checkpoint file from http://download.tensorflow.org/models/vgg_16_2016_08_28.tar.gz and initialize variables with the following code:
model_name='vgg_16'
model_url='http://download.tensorflow.org/models/'
model_files=['vgg_16_2016_08_28.tar.gz']
model_home=os.path.join(models_root,model_name)
dsu.download_dataset(source_url=model_url,
source_files=model_files,
dest_dir = model_home,
force=False,
extract=True)
We also define some common imports and variables:
from tensorflow.contrib import slim
from tensorflow.contrib.slim.nets import vgg
image_height=vgg.vgg_16.default_image_size
image_width=vgg.vgg_16.default_image_size