Fix MaskRCNN conversion bug (#627)

Signed-off-by: Tyler Zhu <tylerz@nvidia.com>

Co-authored-by: Tyler Zhu <tylerz@nvidia.com>

samples/opensource/sampleUffMaskRCNN/converted/0001-Update-the-Mask_RCNN-model-from-NHWC-to-NCHW.patch

@@ -1,4 +1,4 @@
-From 00cfd7d7ce323df1f71048d959681349ca4fed78 Mon Sep 17 00:00:00 2001
+From 9d7ef2f151d7488ddd06e06924dd04e27c9f92b0 Mon Sep 17 00:00:00 2001
 From: Nine Feng <nfeng@nvidia.com>
 Date: Wed, 24 Jul 2019 09:22:44 +0800
 Subject: [PATCH] Update the Mask_RCNN model from NHWC to NCHW
@@ -17,7 +17,7 @@ Subject: [PATCH] Update the Mask_RCNN model from NHWC to NCHW
  2 files changed, 40 insertions(+), 27 deletions(-)
 
 diff --git a/mrcnn/model.py b/mrcnn/model.py
-index 62cb2b0..1508f2c 100644
+index 67c2e4f..d297ae8 100644
 --- a/mrcnn/model.py
 +++ b/mrcnn/model.py
 @@ -110,17 +110,17 @@ def identity_block(input_tensor, kernel_size, filters, stage, block,
@@ -116,23 +116,23 @@ index 62cb2b0..1508f2c 100644
 
 
  ############################################################
-@@ -853,8 +864,9 @@ def rpn_graph(feature_map, anchors_per_location, anchor_stride):
+@@ -853,8 +864,8 @@ def rpn_graph(feature_map, anchors_per_location, anchor_stride):
                    activation='linear', name='rpn_class_raw')(shared)
 
      # Reshape to [batch, anchors, 2]
 -    rpn_class_logits = KL.Lambda(
 -        lambda t: tf.reshape(t, [tf.shape(t)[0], -1, 2]))(x)
 +    x = KL.Permute((2,3,1))(x)
 +    rpn_class_logits = KL.Reshape((-1, 2))(x)
-+    x = KL.Permute((2,3,1))(x)
 
      # Softmax on last dimension of BG/FG.
      rpn_probs = KL.Activation(
-@@ -866,7 +878,7 @@ def rpn_graph(feature_map, anchors_per_location, anchor_stride):
+@@ -866,7 +877,8 @@ def rpn_graph(feature_map, anchors_per_location, anchor_stride):
                    activation='linear', name='rpn_bbox_pred')(shared)
 
      # Reshape to [batch, anchors, 4]
 -    rpn_bbox = KL.Lambda(lambda t: tf.reshape(t, [tf.shape(t)[0], -1, 4]))(x)
++    x = KL.Permute((2,3,1))(x)
 +    rpn_bbox = KL.Reshape((-1, 4))(x)
 
      return [rpn_class_logits, rpn_probs, rpn_bbox]