This repository contains the reference implementation for our proposed Convolutional CRFs in PyTorch (Tensorflow planned). The two main entry-points are demo.py and benchmark.py. Demo.py performs ConvCRF inference on a single input image while benchmark.py compares ConvCRF with FullCRF. Both scripts output plots similar to the one shown below.

Plattform: Linux, python3 >= 3.4 (or python2 >= 2.7), pytorch 0.4 (or pytorch 0.3 + pyinn), cuda, cudnn

Python Packages: numpy, imageio, cython, scikit-image, matplotlib

To install those python packages run pip install -r requirements.txt or pip install numpy imageio cython scikit-image matplotlib. I recommand using a python virtualenv.

Pydensecrf is required to run FullCRF, which is only needed for the benchmark. To install pydensecrf, follow the instructions here or simply run pip install git+https://github.com/lucasb-eyer/pydensecrf.git. Warning Running pip install git+ downloads and installs external code from the internet.

PyINN allows us to write native cuda operations and compile them on-the-fly during runtime. PyINN is used for our initial ConvCRF implementation and required for PyTorch 0.3 users. PyTorch 0.4 introduces an Im2Col layer, making it possible to implement ConvCRFs entirely in PyTorch. PyINN can be used as alternative backend. Run pip install git+https://github.com/szagoruyko/pyinn.git@master to install PyINN.

Demo: Run python demo.py data/2007_001288_0img.png data/2007_001288_5labels.png to perform ConvCRF inference on a single image. Try python demo.py --help to see more options.

Benchmark: Run python benchmark.py data/2007_001288_0img.png data/2007_001288_5labels.png to compare the performance of ConvCRFs to FullCRFs. This script will also tell you how much faster ConvCRFs are. On my system ConvCRF7 is more then 40 and ConvCRF5 more then 60 times faster.

If you benefit from this project, please consider citing our paper.

• Build a native PyTorch 0.4 implementation of ConvCRF
• Provide python 2 implementation
• Build a Tensorflow implementation of ConvCRF