DeepLearningExamples/TensorFlow/Segmentation/UNet_Medical/model/unet.py

50 lines
1.6 KiB
Python

# Copyright (c) 2019, NVIDIA CORPORATION. All rights reserved.
#
# 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.
""" Model construction utils
This module provides a convenient way to create different topologies
based around UNet.
"""
import tensorflow as tf
from model.layers import output_block, upsample_block, bottleneck, downsample_block, input_block
def unet_v1(features, mode):
""" U-Net: Convolutional Networks for Biomedical Image Segmentation
Source:
https://arxiv.org/pdf/1505.04597
"""
skip_connections = []
out, skip = input_block(features, filters=64)
skip_connections.append(skip)
for idx, filters in enumerate([128, 256, 512]):
out, skip = downsample_block(out, filters=filters, idx=idx)
skip_connections.append(skip)
out = bottleneck(out, filters=1024, mode=mode)
for idx, filters in enumerate([512, 256, 128]):
out = upsample_block(out,
residual_input=skip_connections.pop(),
filters=filters,
idx=idx)
return output_block(out, residual_input=skip_connections.pop(), filters=64, n_classes=2)