A CNN model visualizer


Picasso uses Python 3.5+ so use a virtual environment if necessary (e.g. virtualenv env --python=python3) and activate it!

  1. Install with pip or from source.

    With pip:

    pip install picasso-viz

    From the repository:

    git clone git@github.com:merantix/picasso.git
    cd picasso
    pip install -e .

    Note: you’ll need the Tensorflow backend for Keras for these examples to work. Make sure your ~/.keras/keras.json file looks like:

        "backend": "tensorflow",
        "image_dim_ordering": "tf",
        "floatx": "float32",
        "epsilon": 1e-07
  2. Optional (untested!): install Tensorflow with GPU support

    pip uninstall tensorflow
    pip install --upgrade tensorflow-gpu
  3. Start the Flask server

    export FLASK_APP=picasso
    flask run

    Point your browser to and you should see the landing page! When you’re done, Ctrl+C in the terminal to kill your Flask server.

  4. By default, the visualizer starts a Keras MNIST example. We’ve also included a Keras VGG16 example. To use, it you’ll need to get the VGG16 graph and weights. We’ve included a small script to do this.

    1. Setup VGG16:

      python picasso/examples/keras-vgg16/prepare_model.py

      NOTE: if you installed with pip, you’ll need to find the location of this file in the site packages. pip show picasso_viz will tell you the location. For instance, if pip show picasso_viz shows you /home/ryan/test/env/lib/python3.5/site-packages, then the above command should be:

      python /home/ryan/test/env/lib/python3.5/site-packages/picasso/examples/keras-vgg16/prepare_model.py

      If this script fails, you might be behind a proxy. You can download the necessary files manually.

      mkdir ~/.keras/models # If directory doesn't exist
      wget --no-check-certificate -P ~/.keras/models/ https://github.com/fchollet/deep-learning-models/releases/download/v0.1/vgg16_weights_tf_dim_ordering_tf_kernels.h5
      wget --no-check-certificate -P ~/.keras/models/ https://s3.amazonaws.com/deep-learning-models/image-models/imagenet_class_index.json

      Run the script again, and you should be good to go!

    2. Point to the correct configuration (making sure to use the correct path to your directory):

      export PICASSO_SETTINGS=/absolute/path/to/repo/picasso/picasso/examples/keras-vgg16/config.py

      Again, if you installed with pip install picasso-viz, this will look something like:

      export PICASSO_SETTINGS=/home/ryan/test/env/lib/python3.5/site-packages/picasso/examples/keras-vgg16/config.py

      You can check the pip show picasso_viz command for the base directory.

    3. Start Flask flask run. If it worked, the “Current checkpoint” label should have changed on the landing page.

Building the docs

Assuming you’ve cloned the repository, install the required packages:

pip install -e .[docs]

Then build them:

cd docs/
make html

Then you can open _build/html/index.html in your browser of choice.

Running the tests

Install the test requirements:

pip install -e .[test]

Then run with:



  1. This should be considered alpha software. You will encounter bugs and issues. Don’t deploy this to a live server, probably…
  2. Models generated on Keras using the Theano backend should in principle be supported. The only difference is the array ordering of convolutions. I haven’t tried this yet though, so an extra config parameter may be needed.


This package was created with Cookiecutter and the audreyr/cookiecutter-pypackage project template.