pcb defect detetcion application
[ealt-edge.git] / example-apps / PDD / pcb-defect-detection / libs / networks / slim_nets / inception_v2.py
diff --git a/example-apps/PDD/pcb-defect-detection/libs/networks/slim_nets/inception_v2.py b/example-apps/PDD/pcb-defect-detection/libs/networks/slim_nets/inception_v2.py
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+# Copyright 2016 The TensorFlow Authors. 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.
+# ==============================================================================
+"""Contains the definition for inception v2 classification network."""
+
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+
+import tensorflow as tf
+
+from nets import inception_utils
+
+slim = tf.contrib.slim
+trunc_normal = lambda stddev: tf.truncated_normal_initializer(0.0, stddev)
+
+
+def inception_v2_base(inputs,
+                      final_endpoint='Mixed_5c',
+                      min_depth=16,
+                      depth_multiplier=1.0,
+                      scope=None):
+  """Inception v2 (6a2).
+
+  Constructs an Inception v2 network from inputs to the given final endpoint.
+  This method can construct the network up to the layer inception(5b) as
+  described in http://arxiv.org/abs/1502.03167.
+
+  Args:
+    inputs: a tensor of shape [batch_size, height, width, channels].
+    final_endpoint: specifies the endpoint to construct the network up to. It
+      can be one of ['Conv2d_1a_7x7', 'MaxPool_2a_3x3', 'Conv2d_2b_1x1',
+      'Conv2d_2c_3x3', 'MaxPool_3a_3x3', 'Mixed_3b', 'Mixed_3c', 'Mixed_4a',
+      'Mixed_4b', 'Mixed_4c', 'Mixed_4d', 'Mixed_4e', 'Mixed_5a', 'Mixed_5b',
+      'Mixed_5c'].
+    min_depth: Minimum depth value (number of channels) for all convolution ops.
+      Enforced when depth_multiplier < 1, and not an active constraint when
+      depth_multiplier >= 1.
+    depth_multiplier: Float multiplier for the depth (number of channels)
+      for all convolution ops. The value must be greater than zero. Typical
+      usage will be to set this value in (0, 1) to reduce the number of
+      parameters or computation cost of the model.
+    scope: Optional variable_scope.
+
+  Returns:
+    tensor_out: output tensor corresponding to the final_endpoint.
+    end_points: a set of activations for external use, for example summaries or
+                losses.
+
+  Raises:
+    ValueError: if final_endpoint is not set to one of the predefined values,
+                or depth_multiplier <= 0
+  """
+
+  # end_points will collect relevant activations for external use, for example
+  # summaries or losses.
+  end_points = {}
+
+  # Used to find thinned depths for each layer.
+  if depth_multiplier <= 0:
+    raise ValueError('depth_multiplier is not greater than zero.')
+  depth = lambda d: max(int(d * depth_multiplier), min_depth)
+
+  with tf.variable_scope(scope, 'InceptionV2', [inputs]):
+    with slim.arg_scope(
+        [slim.conv2d, slim.max_pool2d, slim.avg_pool2d, slim.separable_conv2d],
+        stride=1, padding='SAME'):
+
+      # Note that sizes in the comments below assume an input spatial size of
+      # 224x224, however, the inputs can be of any size greater 32x32.
+
+      # 224 x 224 x 3
+      end_point = 'Conv2d_1a_7x7'
+      # depthwise_multiplier here is different from depth_multiplier.
+      # depthwise_multiplier determines the output channels of the initial
+      # depthwise conv (see docs for tf.nn.separable_conv2d), while
+      # depth_multiplier controls the # channels of the subsequent 1x1
+      # convolution. Must have
+      #   in_channels * depthwise_multipler <= out_channels
+      # so that the separable convolution is not overparameterized.
+      depthwise_multiplier = min(int(depth(64) / 3), 8)
+      net = slim.separable_conv2d(
+          inputs, depth(64), [7, 7], depth_multiplier=depthwise_multiplier,
+          stride=2, weights_initializer=trunc_normal(1.0),
+          scope=end_point)
+      end_points[end_point] = net
+      if end_point == final_endpoint: return net, end_points
+      # 112 x 112 x 64
+      end_point = 'MaxPool_2a_3x3'
+      net = slim.max_pool2d(net, [3, 3], scope=end_point, stride=2)
+      end_points[end_point] = net
+      if end_point == final_endpoint: return net, end_points
+      # 56 x 56 x 64
+      end_point = 'Conv2d_2b_1x1'
+      net = slim.conv2d(net, depth(64), [1, 1], scope=end_point,
+                        weights_initializer=trunc_normal(0.1))
+      end_points[end_point] = net
+      if end_point == final_endpoint: return net, end_points
+      # 56 x 56 x 64
+      end_point = 'Conv2d_2c_3x3'
+      net = slim.conv2d(net, depth(192), [3, 3], scope=end_point)
+      end_points[end_point] = net
+      if end_point == final_endpoint: return net, end_points
+      # 56 x 56 x 192
+      end_point = 'MaxPool_3a_3x3'
+      net = slim.max_pool2d(net, [3, 3], scope=end_point, stride=2)
+      end_points[end_point] = net
+      if end_point == final_endpoint: return net, end_points
+      # 28 x 28 x 192
+      # Inception module.
+      end_point = 'Mixed_3b'
+      with tf.variable_scope(end_point):
+        with tf.variable_scope('Branch_0'):
+          branch_0 = slim.conv2d(net, depth(64), [1, 1], scope='Conv2d_0a_1x1')
+        with tf.variable_scope('Branch_1'):
+          branch_1 = slim.conv2d(
+              net, depth(64), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_1 = slim.conv2d(branch_1, depth(64), [3, 3],
+                                 scope='Conv2d_0b_3x3')
+        with tf.variable_scope('Branch_2'):
+          branch_2 = slim.conv2d(
+              net, depth(64), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_2 = slim.conv2d(branch_2, depth(96), [3, 3],
+                                 scope='Conv2d_0b_3x3')
+          branch_2 = slim.conv2d(branch_2, depth(96), [3, 3],
+                                 scope='Conv2d_0c_3x3')
+        with tf.variable_scope('Branch_3'):
+          branch_3 = slim.avg_pool2d(net, [3, 3], scope='AvgPool_0a_3x3')
+          branch_3 = slim.conv2d(
+              branch_3, depth(32), [1, 1],
+              weights_initializer=trunc_normal(0.1),
+              scope='Conv2d_0b_1x1')
+        net = tf.concat(axis=3, values=[branch_0, branch_1, branch_2, branch_3])
+        end_points[end_point] = net
+        if end_point == final_endpoint: return net, end_points
+      # 28 x 28 x 256
+      end_point = 'Mixed_3c'
+      with tf.variable_scope(end_point):
+        with tf.variable_scope('Branch_0'):
+          branch_0 = slim.conv2d(net, depth(64), [1, 1], scope='Conv2d_0a_1x1')
+        with tf.variable_scope('Branch_1'):
+          branch_1 = slim.conv2d(
+              net, depth(64), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_1 = slim.conv2d(branch_1, depth(96), [3, 3],
+                                 scope='Conv2d_0b_3x3')
+        with tf.variable_scope('Branch_2'):
+          branch_2 = slim.conv2d(
+              net, depth(64), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_2 = slim.conv2d(branch_2, depth(96), [3, 3],
+                                 scope='Conv2d_0b_3x3')
+          branch_2 = slim.conv2d(branch_2, depth(96), [3, 3],
+                                 scope='Conv2d_0c_3x3')
+        with tf.variable_scope('Branch_3'):
+          branch_3 = slim.avg_pool2d(net, [3, 3], scope='AvgPool_0a_3x3')
+          branch_3 = slim.conv2d(
+              branch_3, depth(64), [1, 1],
+              weights_initializer=trunc_normal(0.1),
+              scope='Conv2d_0b_1x1')
+        net = tf.concat(axis=3, values=[branch_0, branch_1, branch_2, branch_3])
+        end_points[end_point] = net
+        if end_point == final_endpoint: return net, end_points
+      # 28 x 28 x 320
+      end_point = 'Mixed_4a'
+      with tf.variable_scope(end_point):
+        with tf.variable_scope('Branch_0'):
+          branch_0 = slim.conv2d(
+              net, depth(128), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_0 = slim.conv2d(branch_0, depth(160), [3, 3], stride=2,
+                                 scope='Conv2d_1a_3x3')
+        with tf.variable_scope('Branch_1'):
+          branch_1 = slim.conv2d(
+              net, depth(64), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_1 = slim.conv2d(
+              branch_1, depth(96), [3, 3], scope='Conv2d_0b_3x3')
+          branch_1 = slim.conv2d(
+              branch_1, depth(96), [3, 3], stride=2, scope='Conv2d_1a_3x3')
+        with tf.variable_scope('Branch_2'):
+          branch_2 = slim.max_pool2d(
+              net, [3, 3], stride=2, scope='MaxPool_1a_3x3')
+        net = tf.concat(axis=3, values=[branch_0, branch_1, branch_2])
+        end_points[end_point] = net
+        if end_point == final_endpoint: return net, end_points
+      # 14 x 14 x 576
+      end_point = 'Mixed_4b'
+      with tf.variable_scope(end_point):
+        with tf.variable_scope('Branch_0'):
+          branch_0 = slim.conv2d(net, depth(224), [1, 1], scope='Conv2d_0a_1x1')
+        with tf.variable_scope('Branch_1'):
+          branch_1 = slim.conv2d(
+              net, depth(64), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_1 = slim.conv2d(
+              branch_1, depth(96), [3, 3], scope='Conv2d_0b_3x3')
+        with tf.variable_scope('Branch_2'):
+          branch_2 = slim.conv2d(
+              net, depth(96), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_2 = slim.conv2d(branch_2, depth(128), [3, 3],
+                                 scope='Conv2d_0b_3x3')
+          branch_2 = slim.conv2d(branch_2, depth(128), [3, 3],
+                                 scope='Conv2d_0c_3x3')
+        with tf.variable_scope('Branch_3'):
+          branch_3 = slim.avg_pool2d(net, [3, 3], scope='AvgPool_0a_3x3')
+          branch_3 = slim.conv2d(
+              branch_3, depth(128), [1, 1],
+              weights_initializer=trunc_normal(0.1),
+              scope='Conv2d_0b_1x1')
+        net = tf.concat(axis=3, values=[branch_0, branch_1, branch_2, branch_3])
+        end_points[end_point] = net
+        if end_point == final_endpoint: return net, end_points
+      # 14 x 14 x 576
+      end_point = 'Mixed_4c'
+      with tf.variable_scope(end_point):
+        with tf.variable_scope('Branch_0'):
+          branch_0 = slim.conv2d(net, depth(192), [1, 1], scope='Conv2d_0a_1x1')
+        with tf.variable_scope('Branch_1'):
+          branch_1 = slim.conv2d(
+              net, depth(96), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_1 = slim.conv2d(branch_1, depth(128), [3, 3],
+                                 scope='Conv2d_0b_3x3')
+        with tf.variable_scope('Branch_2'):
+          branch_2 = slim.conv2d(
+              net, depth(96), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_2 = slim.conv2d(branch_2, depth(128), [3, 3],
+                                 scope='Conv2d_0b_3x3')
+          branch_2 = slim.conv2d(branch_2, depth(128), [3, 3],
+                                 scope='Conv2d_0c_3x3')
+        with tf.variable_scope('Branch_3'):
+          branch_3 = slim.avg_pool2d(net, [3, 3], scope='AvgPool_0a_3x3')
+          branch_3 = slim.conv2d(
+              branch_3, depth(128), [1, 1],
+              weights_initializer=trunc_normal(0.1),
+              scope='Conv2d_0b_1x1')
+        net = tf.concat(axis=3, values=[branch_0, branch_1, branch_2, branch_3])
+        end_points[end_point] = net
+        if end_point == final_endpoint: return net, end_points
+      # 14 x 14 x 576
+      end_point = 'Mixed_4d'
+      with tf.variable_scope(end_point):
+        with tf.variable_scope('Branch_0'):
+          branch_0 = slim.conv2d(net, depth(160), [1, 1], scope='Conv2d_0a_1x1')
+        with tf.variable_scope('Branch_1'):
+          branch_1 = slim.conv2d(
+              net, depth(128), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_1 = slim.conv2d(branch_1, depth(160), [3, 3],
+                                 scope='Conv2d_0b_3x3')
+        with tf.variable_scope('Branch_2'):
+          branch_2 = slim.conv2d(
+              net, depth(128), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_2 = slim.conv2d(branch_2, depth(160), [3, 3],
+                                 scope='Conv2d_0b_3x3')
+          branch_2 = slim.conv2d(branch_2, depth(160), [3, 3],
+                                 scope='Conv2d_0c_3x3')
+        with tf.variable_scope('Branch_3'):
+          branch_3 = slim.avg_pool2d(net, [3, 3], scope='AvgPool_0a_3x3')
+          branch_3 = slim.conv2d(
+              branch_3, depth(96), [1, 1],
+              weights_initializer=trunc_normal(0.1),
+              scope='Conv2d_0b_1x1')
+        net = tf.concat(axis=3, values=[branch_0, branch_1, branch_2, branch_3])
+        end_points[end_point] = net
+        if end_point == final_endpoint: return net, end_points
+
+      # 14 x 14 x 576
+      end_point = 'Mixed_4e'
+      with tf.variable_scope(end_point):
+        with tf.variable_scope('Branch_0'):
+          branch_0 = slim.conv2d(net, depth(96), [1, 1], scope='Conv2d_0a_1x1')
+        with tf.variable_scope('Branch_1'):
+          branch_1 = slim.conv2d(
+              net, depth(128), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_1 = slim.conv2d(branch_1, depth(192), [3, 3],
+                                 scope='Conv2d_0b_3x3')
+        with tf.variable_scope('Branch_2'):
+          branch_2 = slim.conv2d(
+              net, depth(160), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_2 = slim.conv2d(branch_2, depth(192), [3, 3],
+                                 scope='Conv2d_0b_3x3')
+          branch_2 = slim.conv2d(branch_2, depth(192), [3, 3],
+                                 scope='Conv2d_0c_3x3')
+        with tf.variable_scope('Branch_3'):
+          branch_3 = slim.avg_pool2d(net, [3, 3], scope='AvgPool_0a_3x3')
+          branch_3 = slim.conv2d(
+              branch_3, depth(96), [1, 1],
+              weights_initializer=trunc_normal(0.1),
+              scope='Conv2d_0b_1x1')
+        net = tf.concat(axis=3, values=[branch_0, branch_1, branch_2, branch_3])
+        end_points[end_point] = net
+        if end_point == final_endpoint: return net, end_points
+      # 14 x 14 x 576
+      end_point = 'Mixed_5a'
+      with tf.variable_scope(end_point):
+        with tf.variable_scope('Branch_0'):
+          branch_0 = slim.conv2d(
+              net, depth(128), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_0 = slim.conv2d(branch_0, depth(192), [3, 3], stride=2,
+                                 scope='Conv2d_1a_3x3')
+        with tf.variable_scope('Branch_1'):
+          branch_1 = slim.conv2d(
+              net, depth(192), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_1 = slim.conv2d(branch_1, depth(256), [3, 3],
+                                 scope='Conv2d_0b_3x3')
+          branch_1 = slim.conv2d(branch_1, depth(256), [3, 3], stride=2,
+                                 scope='Conv2d_1a_3x3')
+        with tf.variable_scope('Branch_2'):
+          branch_2 = slim.max_pool2d(net, [3, 3], stride=2,
+                                     scope='MaxPool_1a_3x3')
+        net = tf.concat(axis=3, values=[branch_0, branch_1, branch_2])
+        end_points[end_point] = net
+        if end_point == final_endpoint: return net, end_points
+      # 7 x 7 x 1024
+      end_point = 'Mixed_5b'
+      with tf.variable_scope(end_point):
+        with tf.variable_scope('Branch_0'):
+          branch_0 = slim.conv2d(net, depth(352), [1, 1], scope='Conv2d_0a_1x1')
+        with tf.variable_scope('Branch_1'):
+          branch_1 = slim.conv2d(
+              net, depth(192), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_1 = slim.conv2d(branch_1, depth(320), [3, 3],
+                                 scope='Conv2d_0b_3x3')
+        with tf.variable_scope('Branch_2'):
+          branch_2 = slim.conv2d(
+              net, depth(160), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_2 = slim.conv2d(branch_2, depth(224), [3, 3],
+                                 scope='Conv2d_0b_3x3')
+          branch_2 = slim.conv2d(branch_2, depth(224), [3, 3],
+                                 scope='Conv2d_0c_3x3')
+        with tf.variable_scope('Branch_3'):
+          branch_3 = slim.avg_pool2d(net, [3, 3], scope='AvgPool_0a_3x3')
+          branch_3 = slim.conv2d(
+              branch_3, depth(128), [1, 1],
+              weights_initializer=trunc_normal(0.1),
+              scope='Conv2d_0b_1x1')
+        net = tf.concat(axis=3, values=[branch_0, branch_1, branch_2, branch_3])
+        end_points[end_point] = net
+        if end_point == final_endpoint: return net, end_points
+
+      # 7 x 7 x 1024
+      end_point = 'Mixed_5c'
+      with tf.variable_scope(end_point):
+        with tf.variable_scope('Branch_0'):
+          branch_0 = slim.conv2d(net, depth(352), [1, 1], scope='Conv2d_0a_1x1')
+        with tf.variable_scope('Branch_1'):
+          branch_1 = slim.conv2d(
+              net, depth(192), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_1 = slim.conv2d(branch_1, depth(320), [3, 3],
+                                 scope='Conv2d_0b_3x3')
+        with tf.variable_scope('Branch_2'):
+          branch_2 = slim.conv2d(
+              net, depth(192), [1, 1],
+              weights_initializer=trunc_normal(0.09),
+              scope='Conv2d_0a_1x1')
+          branch_2 = slim.conv2d(branch_2, depth(224), [3, 3],
+                                 scope='Conv2d_0b_3x3')
+          branch_2 = slim.conv2d(branch_2, depth(224), [3, 3],
+                                 scope='Conv2d_0c_3x3')
+        with tf.variable_scope('Branch_3'):
+          branch_3 = slim.max_pool2d(net, [3, 3], scope='MaxPool_0a_3x3')
+          branch_3 = slim.conv2d(
+              branch_3, depth(128), [1, 1],
+              weights_initializer=trunc_normal(0.1),
+              scope='Conv2d_0b_1x1')
+        net = tf.concat(axis=3, values=[branch_0, branch_1, branch_2, branch_3])
+        end_points[end_point] = net
+        if end_point == final_endpoint: return net, end_points
+    raise ValueError('Unknown final endpoint %s' % final_endpoint)
+
+
+def inception_v2(inputs,
+                 num_classes=1000,
+                 is_training=True,
+                 dropout_keep_prob=0.8,
+                 min_depth=16,
+                 depth_multiplier=1.0,
+                 prediction_fn=slim.softmax,
+                 spatial_squeeze=True,
+                 reuse=None,
+                 scope='InceptionV2'):
+  """Inception v2 model for classification.
+
+  Constructs an Inception v2 network for classification as described in
+  http://arxiv.org/abs/1502.03167.
+
+  The default image size used to train this network is 224x224.
+
+  Args:
+    inputs: a tensor of shape [batch_size, height, width, channels].
+    num_classes: number of predicted classes.
+    is_training: whether is training or not.
+    dropout_keep_prob: the percentage of activation values that are retained.
+    min_depth: Minimum depth value (number of channels) for all convolution ops.
+      Enforced when depth_multiplier < 1, and not an active constraint when
+      depth_multiplier >= 1.
+    depth_multiplier: Float multiplier for the depth (number of channels)
+      for all convolution ops. The value must be greater than zero. Typical
+      usage will be to set this value in (0, 1) to reduce the number of
+      parameters or computation cost of the model.
+    prediction_fn: a function to get predictions out of logits.
+    spatial_squeeze: if True, logits is of shape [B, C], if false logits is
+        of shape [B, 1, 1, C], where B is batch_size and C is number of classes.
+    reuse: whether or not the network and its variables should be reused. To be
+      able to reuse 'scope' must be given.
+    scope: Optional variable_scope.
+
+  Returns:
+    logits: the pre-softmax activations, a tensor of size
+      [batch_size, num_classes]
+    end_points: a dictionary from components of the network to the corresponding
+      activation.
+
+  Raises:
+    ValueError: if final_endpoint is not set to one of the predefined values,
+                or depth_multiplier <= 0
+  """
+  if depth_multiplier <= 0:
+    raise ValueError('depth_multiplier is not greater than zero.')
+
+  # Final pooling and prediction
+  with tf.variable_scope(scope, 'InceptionV2', [inputs, num_classes],
+                         reuse=reuse) as scope:
+    with slim.arg_scope([slim.batch_norm, slim.dropout],
+                        is_training=is_training):
+      net, end_points = inception_v2_base(
+          inputs, scope=scope, min_depth=min_depth,
+          depth_multiplier=depth_multiplier)
+      with tf.variable_scope('Logits'):
+        kernel_size = _reduced_kernel_size_for_small_input(net, [7, 7])
+        net = slim.avg_pool2d(net, kernel_size, padding='VALID',
+                              scope='AvgPool_1a_{}x{}'.format(*kernel_size))
+        # 1 x 1 x 1024
+        net = slim.dropout(net, keep_prob=dropout_keep_prob, scope='Dropout_1b')
+        logits = slim.conv2d(net, num_classes, [1, 1], activation_fn=None,
+                             normalizer_fn=None, scope='Conv2d_1c_1x1')
+        if spatial_squeeze:
+          logits = tf.squeeze(logits, [1, 2], name='SpatialSqueeze')
+      end_points['Logits'] = logits
+      end_points['Predictions'] = prediction_fn(logits, scope='Predictions')
+  return logits, end_points
+inception_v2.default_image_size = 224
+
+
+def _reduced_kernel_size_for_small_input(input_tensor, kernel_size):
+  """Define kernel size which is automatically reduced for small input.
+
+  If the shape of the input images is unknown at graph construction time this
+  function assumes that the input images are is large enough.
+
+  Args:
+    input_tensor: input tensor of size [batch_size, height, width, channels].
+    kernel_size: desired kernel size of length 2: [kernel_height, kernel_width]
+
+  Returns:
+    a tensor with the kernel size.
+
+  TODO(jrru): Make this function work with unknown shapes. Theoretically, this
+  can be done with the code below. Problems are two-fold: (1) If the shape was
+  known, it will be lost. (2) inception.slim.ops._two_element_tuple cannot
+  handle tensors that define the kernel size.
+      shape = tf.shape(input_tensor)
+      return = tf.pack([tf.minimum(shape[1], kernel_size[0]),
+                        tf.minimum(shape[2], kernel_size[1])])
+
+  """
+  shape = input_tensor.get_shape().as_list()
+  if shape[1] is None or shape[2] is None:
+    kernel_size_out = kernel_size
+  else:
+    kernel_size_out = [min(shape[1], kernel_size[0]),
+                       min(shape[2], kernel_size[1])]
+  return kernel_size_out
+
+
+inception_v2_arg_scope = inception_utils.inception_arg_scope