SpecAnaSyn
Spectral Analysis and Synthesis of Sounds
...For the analysis phase an STFT is done (using libfftw for doing FFTs), and then harmonic/sinusoidal analysis. For the synthesis phase additive synthesis is used. Using libsndfile for sound loading and saving allows to support many uncompressed sound file formats (WAV, AIFF, AU, headerless RAW, ...), and also OGG and FLAC, but MP3 isn't supported.
Available parameters include window type, size, and overlapping; sinusoid discarding; equalization; time strechting, frequency scaling and shifting; frequency and amplitude interpolation; normalization; dynamic range compression and expansion, etc.
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