Siamese Network using Rstudio Keras
I'm trying to implement a siamese network using Rstudio Keras package. The network I'm trying to implement is the same network that you can see in this post.
So, basically, I'm porting the code to R and using Rstudio Keras implementation. So far my code looks like this:
library(keras)
inputShape <- c(105, 105, 1)
leftInput <- layer_input(inputShape)
rightInput <- layer_input(inputShape)
model<- keras_model_sequential()
model %>%
layer_conv_2d(filter=64,
kernel_size=c(10,10),
activation = "relu",
input_shape=inputShape,
kernel_initializer = initializer_random_normal(0, 1e-2),
kernel_regularizer = regularizer_l2(2e-4)) %>%
layer_max_pooling_2d() %>%
layer_conv_2d(filter=128,
kernel_size=c(7,7),
activation = "relu",
kernel_initializer = initializer_random_normal(0, 1e-2),
kernel_regularizer = regularizer_l2(2e-4),
bias_initializer = initializer_random_normal(0.5, 1e-2)) %>%
layer_max_pooling_2d() %>%
layer_conv_2d(filter=128,
kernel_size=c(4,4),
activation = "relu",
kernel_initializer = initializer_random_normal(0, 1e-2),
kernel_regularizer = regularizer_l2(2e-4),
bias_initializer = initializer_random_normal(0.5, 1e-2)) %>%
layer_max_pooling_2d() %>%
layer_conv_2d(filter=256,
kernel_size=c(4,4),
activation = "relu",
kernel_initializer = initializer_random_normal(0, 1e-2),
kernel_regularizer = regularizer_l2(2e-4),
bias_initializer = initializer_random_normal(0.5, 1e-2)) %>%
layer_flatten() %>%
layer_dense(4096,
activation = "sigmoid",
kernel_initializer = initializer_random_normal(0, 1e-2),
kernel_regularizer = regularizer_l2(1e-3),
bias_initializer = initializer_random_normal(0.5, 1e-2))
encoded_left <- leftInput %>% model
encoded_right <- rightInput %>% model
However, when running the last two lines, I get the following error:
Error in py_call_impl(callable, dots$args, dots$keywords) :
AttributeError: 'Model' object has no attribute '_losses'
Detailed traceback:
File "/home/rstudio/.virtualenvs/r-tensorflow/lib/python2.7/site-packages/tensorflow/contrib/keras/python/keras/engine/topology.py", line 432, in __call__
output = super(Layer, self).__call__(inputs, **kwargs)
File "/home/rstudio/.virtualenvs/r-tensorflow/lib/python2.7/site-packages/tensorflow/python/layers/base.py", line 441, in __call__
outputs = self.call(inputs, *args, **kwargs)
File "/home/rstudio/.virtualenvs/r-tensorflow/lib/python2.7/site-packages/tensorflow/contrib/keras/python/keras/models.py", line 560, in call
return self.model.call(inputs, mask)
File "/home/rstudio/.virtualenvs/r-tensorflow/lib/python2.7/site-packages/tensorflow/contrib/keras/python/keras/engine/topology.py", line 1743, in call
output_tensors, _, _ = self.run_internal_graph(inputs, masks)
File "/home/rstudio/.virtualenvs/r-tensorflow/lib/python2.7/site-packages/tensorflow/contrib/keras/python
I have been looking at similar implementations and questions all over StackOverflow, but I could not find a solution. I think I might be missing something really obvious.
Any ideas how to solve this?
Solution 1:
As pointed out by Daniel Falbel in his comment, the solution was updating R-keras package and then updating the tensorflow installation.
However, tensorflow package in R was not installing the latest 1.3 tensorflow version (it was reinstalling the 1.2 version).
To fix this problem, the URL to the correct version can be supplied to the install_tensorflow function. The URLs for the different implementations can be found here. I was using Linux in this case. Running this command should solve the problem for anyone who comes across the same issue:
library(tensorflow)
install_tensorflow(package_url = "https://pypi.python.org/packages/b8/d6/af3d52dd52150ec4a6ceb7788bfeb2f62ecb6aa2d1172211c4db39b349a2/tensorflow-1.3.0rc0-cp27-cp27mu-manylinux1_x86_64.whl#md5=1cf77a2360ae2e38dd3578618eacc03b")
Solution 2:
I tried GAN and also got this error. When I use the same code on the CPU version of tensorflow is was ok, but on the GPU version wasn't.
I found that this problem was caused by using the kernel_regularizer
parameter on the GPU version. You can remove the parameter and try it again. I don't know why this solved the issue. I guess it may be a bug when processing reused models.