Getting model activations with K.function doesn't work since v2.2.0

Hi there,

I’m running into problems with getting the activations of a model using K.function since Keras 2.2.0. With 2.1.6, everything works fine. I’m using the tensorflow backend with a convnet with multiple outputs.

A (shortened) code snippet can be found below:

saved_model = ks.models.load_model('...') # the model has been saved with 2.2.0
inp = saved_model.input

generator = generate_batches_from_hdf5_file(...)
model_inputs, ys = next(generator) 
lp = 0. if learning_phase == 'test' else 1.

outputs = [layer.output for layer in saved_model.layers if
               layer.name == layer_name or layer_name is None]  # all layer outputs -> empty tf.tensors 

funcs = [K.function([inp] + [K.learning_phase()], [out]) for out in outputs]  # evaluation functions

list_inputs = [model_inputs, lp]

layer_outputs = [func(list_inputs)[0] for func in funcs] <- throws an error since Keras 2.2.0
...

The last line yields the following error since 2.2.0:

File ".../visualization_tools.py", line 135, in get_activations_and_weights
    layer_outputs = [func(list_inputs)[0] for func in funcs]
  File "/home/hpc/capn/mppi033h/.local/lib/python2.7/site-packages/keras/backend/tensorflow_backend.py", line 2661, in __call__
    return self._call(inputs)
  File "/home/hpc/capn/mppi033h/.local/lib/python2.7/site-packages/keras/backend/tensorflow_backend.py", line 2630, in _call
    session)
  File "/home/hpc/capn/mppi033h/.local/lib/python2.7/site-packages/keras/backend/tensorflow_backend.py", line 2582, in _make_callable
    callable_fn = session._make_callable_from_options(callable_opts)
  File "/home/hpc/capn/mppi033h/.local/lib/python2.7/site-packages/tensorflow/python/client/session.py", line 1480, in _make_callable_from_options
    return BaseSession._Callable(self, callable_options)
  File "/home/hpc/capn/mppi033h/.local/lib/python2.7/site-packages/tensorflow/python/client/session.py", line 1441, in __init__
    session._session, options_ptr, status)
  File "/home/hpc/capn/mppi033h/.local/lib/python2.7/site-packages/tensorflow/python/framework/errors_impl.py", line 519, in __exit__
    c_api.TF_GetCode(self.status.status))
tensorflow.python.framework.errors_impl.InvalidArgumentError: input_1_1:0 is both fed and fetched.
Exception tensorflow.python.framework.errors_impl.InvalidArgumentError: InvalidArgumentError() in <bound method _Callable.__del__ of <tensorflow.python.client.session._Callable object at 0x7f35b1f20a10>> ignored

Any idea what could have changed in 2.2.0?

[yanboliang]

@ViaFerrata After checking your code, I found the input_layer was passed into both feed and fetch. This is illegal for TF since keras switch to use tf.Session._make_callable_from_options. You can insert outputs = outputs[1:] before

funcs = [K.function(inp + [K.learning_phase()], [out]) for out in outputs]

to remove the first input_layer from fetch, then it can work well.

[JennaElli]

Similar issue here too. I’m trying to run the example script for ‘Activation Maximization on VGGNet’.

Traceback (most recent call last): File “kvis.py”, line 24, in <module> img = visualize_activation(model, layer_idx, filter_indices=20) File “/home/ycc62267/.local/lib/python3.6/site-packages/vis/visualization/activation_maximization.py”, line 107, in visualize_activation return visualize_activation_with_losses(model.input, losses, seed_input, input_range, **optimizer_params) File “/home/ycc62267/.local/lib/python3.6/site-packages/vis/visualization/activation_maximization.py”, line 41, in visualize_activation_with_losses img = opt.minimize(**optimizer_params)[0] File “/home/ycc62267/.local/lib/python3.6/site-packages/vis/optimizer.py”, line 143, in minimize computed_values = self.compute_fn([seed_input, 0]) File “/dls_sw/apps/python/anaconda/1.7.0/64/envs/python3/lib/python3.6/site-packages/keras/backend/tensorflow_backend.py”, line 2661, in call return self._call(inputs) File “/dls_sw/apps/python/anaconda/1.7.0/64/envs/python3/lib/python3.6/site-packages/keras/backend/tensorflow_backend.py”, line 2630, in _call session) File “/dls_sw/apps/python/anaconda/1.7.0/64/envs/python3/lib/python3.6/site-packages/keras/backend/tensorflow_backend.py”, line 2582, in _make_callable callable_fn = session._make_callable_from_options(callable_opts) File “/dls_sw/apps/python/anaconda/1.7.0/64/envs/python3/lib/python3.6/site-packages/tensorflow/python/client/session.py”, line 1480, in _make_callable_from_options return BaseSession._Callable(self, callable_options) File “/dls_sw/apps/python/anaconda/1.7.0/64/envs/python3/lib/python3.6/site-packages/tensorflow/python/client/session.py”, line 1441, in init session._session, options_ptr, status) File “/dls_sw/apps/python/anaconda/1.7.0/64/envs/python3/lib/python3.6/site-packages/tensorflow/python/framework/errors_impl.py”, line 519, in exit c_api.TF_GetCode(self.status.status)) tensorflow.python.framework.errors_impl.InvalidArgumentError: input_1_1:0 is both fed and fetched. Exception ignored in: <bound method BaseSession._Callable.del of <tensorflow.python.client.session.BaseSession._Callable object at 0x7f1417e97be0>> Traceback (most recent call last): File “/dls_sw/apps/python/anaconda/1.7.0/64/envs/python3/lib/python3.6/site-packages/tensorflow/python/client/session.py”, line 1464, in del self._session._session, self._handle, status) File “/dls_sw/apps/python/anaconda/1.7.0/64/envs/python3/lib/python3.6/site-packages/tensorflow/python/framework/errors_impl.py”, line 519, in exit c_api.TF_GetCode(self.status.status)) tensorflow.python.framework.errors_impl.InvalidArgumentError: No such callable handle: 139726883220512