ValueError: The shape of the input to "Flatten" is not fully defined

[muthiyanbhushan]

Hello @pplonski,

Thank you for this tutorial to convert simple keras to cpp.

when I run the first command to generate ".h5 " and ".json" file I get following error:

I tried changing backends to both Theano and Tensorflow in keras.json file but still could not resolve this error.

$ python example/mnist_cnn_one_iteration.py

error:

Using Theano backend.
X_train shape: (60000, 1, 28, 28)
60000 train samples
10000 test samples
example/mnist_cnn_one_iteration.py:49: UserWarning: Update your Conv2D call to the Keras 2 API: Conv2D(4, (3, 3), padding="same", input_shape=(1, 28, 28...)
model.add(Convolution2D(nb_filters, nb_conv, nb_conv, border_mode='same',input_shape=(1, img_rows, img_cols)))
example/mnist_cnn_one_iteration.py:51: UserWarning: Update your Conv2D call to the Keras 2 API: Conv2D(4, (3, 3), padding="same")
model.add(Convolution2D(nb_filters, nb_conv, nb_conv, border_mode='same'))
Traceback (most recent call last):
File "example/mnist_cnn_one_iteration.py", line 56, in
model.add(Flatten())
File "/usr/local/lib/python2.7/dist-packages/keras/models.py", line 476, in add
output_tensor = layer(self.outputs[0])
File "/usr/local/lib/python2.7/dist-packages/keras/engine/topology.py", line 615, in call
output_shape = self.compute_output_shape(input_shape)
File "/usr/local/lib/python2.7/dist-packages/keras/layers/core.py", line 481, in compute_output_shape
'(got ' + str(input_shape[1:]) + '. '
ValueError: The shape of the input to "Flatten" is not fully defined (got (0, 14, 4). Make sure to pass a complete "input_shape" or "batch_input_shape" argument to the first layer in your model.

My keras.json file looks like:

{
"image_dim_ordering": "th",
"epsilon": 1e-07,
"floatx": "float32",
"backend": "theano"
}

Please let me know about it.

Thank you.

Regards,
Bhushan

[pplonski]

Hi! I think it can be problem with keras 2.0, it is not tested, could you try with keras 1.2.2 ?

[muthiyanbhushan]

Hello pplonski,

I resolved that issue by changing to keras 1.2.2 but now another issue with Theano ifelse condition

$ python example/mnist_cnn_one_iteration.py

Using Theano backend.
Downloading data from https://s3.amazonaws.com/img-datasets/mnist.pkl.gz
15302656/15296311 [==============================] - 2s
X_train shape: (60000, 1, 28, 28)
60000 train samples
10000 test samples
Traceback (most recent call last):
File "example/mnist_cnn_one_iteration.py", line 54, in
model.add(Dropout(0.25))
File "/usr/local/lib/python2.7/dist-packages/keras/models.py", line 327, in add
output_tensor = layer(self.outputs[0])
File "/usr/local/lib/python2.7/dist-packages/keras/engine/topology.py", line 569, in call
self.add_inbound_node(inbound_layers, node_indices, tensor_indices)
File "/usr/local/lib/python2.7/dist-packages/keras/engine/topology.py", line 632, in add_inbound_node
Node.create_node(self, inbound_layers, node_indices, tensor_indices)
File "/usr/local/lib/python2.7/dist-packages/keras/engine/topology.py", line 164, in create_node
output_tensors = to_list(outbound_layer.call(input_tensors[0], mask=input_masks[0]))
File "/usr/local/lib/python2.7/dist-packages/keras/layers/core.py", line 90, in call
x = K.in_train_phase(K.dropout(x, self.p, noise_shape), x)
File "/usr/local/lib/python2.7/dist-packages/keras/backend/theano_backend.py", line 1120, in in_train_phase
x = theano.ifelse.ifelse(_LEARNING_PHASE, x, alt)
AttributeError: 'module' object has no attribute 'ifelse'

Thanks for your help.

Bhushan

[peacherwu]

Probably you have resolved this issue, just for the sake of completeness.

You can modify the .../theano_backend.py according to this:
https://stackoverflow.com/questions/46253744/getting-error-attributeerror-module-object-has-no-attribute-ifelse