# Is it possible to perform p5js.sound FFT for the whole audio input without playing it back?

**URL:** <https://discourse.processing.org/t/is-it-possible-to-perform-p5js-sound-fft-for-the-whole-audio-input-without-playing-it-back/12318>\
**Category:** Libraries\
**Created:** [June 26, 2019, 6:10pm UTC](https://discourse.processing.org/t/is-it-possible-to-perform-p5js-sound-fft-for-the-whole-audio-input-without-playing-it-back/12318 "2019-06-26T18:10:15Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![fftnana](https://avatars.discourse-cdn.com/v4/letter/f/9de053/32.png) [@fftnana](https://discourse.processing.org/u/fftnana)\
**Post date:** [June 26, 2019, 6:10pm UTC](https://discourse.processing.org/t/is-it-possible-to-perform-p5js-sound-fft-for-the-whole-audio-input-without-playing-it-back/12318/1 "2019-06-26T18:10:15Z")

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Hi all,

I am currently working on an audio plotting/visualizer project which takes in amplitude of the audio input and also FFT for more data, so that the resulting plot/image will be more variative.

As for amplitude, I can grab the amplitude of the whole input by modifying p5.sound.getPeaks(). However, as for FFT, it seems that it requires playback though… Does anyone have an idea to tackle this problem as I don’t want to play it back because I want to plot it at once into a static image instead of animation…

Thank You…

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**Author:** ![jeremydouglass](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/jeremydouglass/32/20_2.png) [@jeremydouglass](https://discourse.processing.org/u/jeremydouglass)\
**Post date:** [July 5, 2019, 2:24pm UTC](https://discourse.processing.org/t/is-it-possible-to-perform-p5js-sound-fft-for-the-whole-audio-input-without-playing-it-back/12318/2 "2019-07-05T14:24:14Z")

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Possibly something with WebAudio and OfflineAudioContext?

> <https://stackoverflow.com/questions/8074152/is-there-a-way-to-use-the-web-audio-api-to-sample-audio-faster-than-real-time/8101383#8101383>

> <https://stackoverflow.com/questions/8074152/is-there-a-way-to-use-the-web-audio-api-to-sample-audio-faster-than-real-time/29651911#29651911>

Possibly also:

> <https://stackoverflow.com/questions/13590999/offline-non-realtime-rendering-with-the-web-audio-api>