Gabriel Peyré on Twitter: "The spectrogram (aka short time Fourier transform) reveals the geometry of sounds. Evolving harmonics of a birds singing become smooth curves. Sounds are intrinsically (at least) 2-D (time-frequency).
![Anna University Wikipedia University of Toronto Lund University, Fast Fourier Transform, angle, digital png | PNGEgg Anna University Wikipedia University of Toronto Lund University, Fast Fourier Transform, angle, digital png | PNGEgg](https://e7.pngegg.com/pngimages/910/242/png-clipart-anna-university-wikipedia-university-of-toronto-lund-university-fast-fourier-transform-angle-digital.png)
Anna University Wikipedia University of Toronto Lund University, Fast Fourier Transform, angle, digital png | PNGEgg
Gabriel Peyré on Twitter: "Representation theory defines a Fourier transform on groups. Finite commutative groups correspond to the classical discrete Fourier transform. https://t.co/Kany2ueLmN https://t.co/agPR4YMypg https://t.co/V3LsEBEPPX" / Twitter
![Fourier transform infrared spectroscopy - Wikipedia, the free encyclopedia | Chimie, Science, Astronomie Fourier transform infrared spectroscopy - Wikipedia, the free encyclopedia | Chimie, Science, Astronomie](https://i.pinimg.com/474x/b7/0a/36/b70a3634b756d522f3b949f2dfd24b42--astrophysics-mathematics.jpg)