This SW is released under both 3-clause BSD and Boost licenses. Note that this SW uses OpenCV. Please see relevant license files for that project.
See:
LICNESE.bsd LICENSE.boost
A concise implementation of separable steerable filters via Freeman and Adelson, including second derivative of Gaussian and its Hilbert transform (G2 H2), implemented with the OpenCV C++ API
wget https://github.com/ruslo/polly/archive/master.zip unzip master.zip POLLY_ROOT="`pwd`/polly-master" export PATH="${POLLY_ROOT}/bin:${PATH}"
polly.py --install --reconfig --verbose --fwd CVSTEER_BUILD_EXAMPLE=ON
_install/default/bin/cvsteer-run --input=/tmp/some_file.png --output=/tmp --gain=1.0