Essentia is the result of more than 10 years of research and development at Music Technology Group and it incorporates the work done by many researchers during all this time. The library has been designed to support large-scale industrial applications. It is being used to support applications such as music and sound classification, semantic auto-tagging, music similarity and recommendation, visualization and interaction with music, sound indexing, musical instruments detection, cover detection, and beat detection among many others.
Essentia is available under an open licence, Affero GPLv3, for non-commercial applications, thus it is possible to test the library before deciding to licence it under a comercial licence.
Contact Music Technology Group (UPF) for more information about licensing conditions and for consulting how Essentia can suit your application.
Some Essentia library algorithms use third-party libraries with licenses such as GPL, LGPL, and others for which UPF is not able to provide full sublicensing rights to third parties. If a third party plans to release a product based on Essentia, it needs to make sure to have cleared the rights over the required libraries for itself.
Essentia can interoperate with these libraries but it does not force any third-party application to use them. It is possible to compile Essentia with reduced dependencies ignoring undesired 3rd-party libraries and algorithms. UPF will not be liable for any illegal use of these libraries.
This is the set of libraries which can be used within Essentia:
GPL (with dual license option to allow Commercial license. Commercial license has to be obtained from the software author)
NNLS Chroma - http://www.isophonics.net/nnls-chroma – used by LogSpectrum and NNLSChroma algorithms. Alternatively, Essentia’s ConstantQ and HPCP native algorithms should provide equilavent results.
LGPL (the original copyright notice as well as a copy of the LGPL has to be supplied This can be achieved through dynamic linking)
libavcodec/libavformat/libavutil/libavresample - https://www.ffmpeg.org - used by the AudioLoader, MonoLoader, EasyLoader and EqloudLoader algorithms
Taglib - http://developer.kde.org/~wheeler/taglib.html - used by the MetadataReader algorithm
Chromaprint - https://github.com/acoustid/chromaprint - used by the Chromaprinter algorithm
splineutil.hpp and splineutil.cpp - http://people.sc.fsu.edu/~jburkardt/cpp_src/spline/spline.html - used by the Spline and CubicSpline algorithms
Others (the original copyright notice must be retained. They can be linked dynamically or statically)
Libsamplerate - http://www.mega-nerd.com/SRC/ - used by the Resample algorithm, and MonoLoader, EasyLoader and EqloudLoader. Originally released under GPL, it is licensed under BSD-2-Clause since 2016
MersenneTwister - http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/emt.html (BSD-style license)
NumPy - http://www.numpy.org/
Accelerate - https://developer.apple.com/reference/accelerate