KFR

KFR is an industry-proven open-source/commercial C++ DSP library and is packed with optimised building blocks for creating audio applications and plug-ins.

It is dual-licensed under GPLv2+ and a commercial license.

Among its features:

• Discrete Fourier Transform (aka DFT), Fast Fourier Transform (aka FFT) and related algorithms, such as convolution and correlation.
• High quality Sample Rate Conversion.
• Biquad filters and filter design.
• IIR filter design.
• FIR filters and design.
• EBU R 128 Loudness.
• Window functions.
• Tensor and matrix operations.
• Goertzel, Stereo mixing, DC removal, A-, B- and C- weighting.
• Mathematical and statistical functions.
• Audio file reading/writing.
• Pseudorandom number generator.