Skip to main content

A PyTorch framework for developing memory efficient deep invertible networks.

Project description

CircleCI - Status master branch Docker - Status Documentation - Status master branch Codacy - Branch grade Codecov - Status master branch PyPI - Latest release Conda - Latest release PyPI - Implementation PyPI - Python version GitHub - Repository license JOSS - DOI

A PyTorch framework for developing memory-efficient invertible neural networks.


  • Enable memory savings during training by wrapping arbitrary invertible PyTorch functions with the InvertibleModuleWrapper class.

  • Simple toggling of memory saving by setting the keep_input property of the InvertibleModuleWrapper.

  • Turn arbitrary non-linear PyTorch functions into invertible versions using the AdditiveCoupling or the AffineCoupling classes.

  • Training and evaluation code for reproducing RevNet experiments using MemCNN.

  • CI tests for Python v3.7 and torch v1.0, v1.1, v1.4 and v1.7 with good code coverage.


Creating an AdditiveCoupling with memory savings

import torch
import torch.nn as nn
import memcnn

# define a new torch Module with a sequence of operations: Relu o BatchNorm2d o Conv2d
class ExampleOperation(nn.Module):
    def __init__(self, channels):
        super(ExampleOperation, self).__init__()
        self.seq = nn.Sequential(
                                    nn.Conv2d(in_channels=channels, out_channels=channels,
                                              kernel_size=(3, 3), padding=1),

    def forward(self, x):
        return self.seq(x)

# generate some random input data (batch_size, num_channels, y_elements, x_elements)
X = torch.rand(2, 10, 8, 8)

# application of the operation(s) the normal way
model_normal = ExampleOperation(channels=10)

Y = model_normal(X)

# turn the ExampleOperation invertible using an additive coupling
invertible_module = memcnn.AdditiveCoupling(
    Fm=ExampleOperation(channels=10 // 2),
    Gm=ExampleOperation(channels=10 // 2)

# test that it is actually a valid invertible module (has a valid inverse method)
assert memcnn.is_invertible_module(invertible_module, test_input_shape=X.shape)

# wrap our invertible_module using the InvertibleModuleWrapper and benefit from memory savings during training
invertible_module_wrapper = memcnn.InvertibleModuleWrapper(fn=invertible_module, keep_input=True, keep_input_inverse=True)

# by default the module is set to training, the following sets this to evaluation
# note that this is required to pass input tensors to the model with requires_grad=False (inference only)

# test that the wrapped module is also a valid invertible module
assert memcnn.is_invertible_module(invertible_module_wrapper, test_input_shape=X.shape)

# compute the forward pass using the wrapper
Y2 = invertible_module_wrapper.forward(X)

# the input (X) can be approximated (X2) by applying the inverse method of the wrapper on Y2
X2 = invertible_module_wrapper.inverse(Y2)

# test that the input and approximation are similar
assert torch.allclose(X, X2, atol=1e-06)

Run PyTorch Experiments

After installing MemCNN run:

python -m memcnn.train [MODEL] [DATASET] [--fresh] [--no-cuda]
  • Available values for DATASET are cifar10 and cifar100.

  • Available values for MODEL are resnet32, resnet110, resnet164, revnet38, revnet110, revnet164

  • Use the --fresh flag to remove earlier experiment results.

  • Use the --no-cuda flag to train on the CPU rather than the GPU through CUDA.

Datasets are automatically downloaded if they are not available.

When using Python 3.* replace the python directive with the appropriate Python 3 directive. For example when using the MemCNN docker image use python3.6.

When MemCNN was installed using pip or from sources you might need to setup a configuration file before running this command. Read the corresponding section about how to do this here:

Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

memcnn-1.5.2.tar.gz (50.6 kB view hashes)

Uploaded source

Built Distribution

memcnn-1.5.2-py2.py3-none-any.whl (50.3 kB view hashes)

Uploaded py2 py3

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page