Write a React-Native library to change Pitch (Frequency) of mp3

Hi everyone, hope you're having an amazing day! I am working on a react-native app in the sound niche.

This is basically what I need:


"[login to view URL]"


"[login to view URL]" pitch has changed to a different frequency without changing tempo

How the code could look like in react-native:

[login to view URL]("[login to view URL]", "[login to view URL]", "A4"); //A4 is the musical note, frequency of 440 hz

So all I want is 1 line of code which I can use in React-Native that changes the pitch without changing tempo.

If you know Audacity, it has an Effect called "Change Pitch (without Changing Tempo)". I basically want to do this in a react-native app. I have already done extensive research, but couldn't find a working way so far.

I tried it with ffmpeg and I am actually able to change the pitch without changing tempo, but I don't know what frequency or what pitch it is.

This is the command I am using to change a pitch. But I want to be able to change it to a musical note C5 for example.

" ffmpeg -i [login to view URL] -af asetrate=44100*0.9,aresample=44100,atempo=1.1 [login to view URL]"

Here is what it is supposed to mapped with [login to view URL]~suits/[login to view URL]


[login to view URL] is recognized at Frequency 440 hz (musical note A4)


[login to view URL] is now at Frequency 587 hz (musical note D5)

How the code could look like in react-native:

[login to view URL]("[login to view URL]", "[login to view URL]", "A4"); //A4 is the musical note, frequency of 440 hz

Solutions would be:

1. Write own native library in iOS / Android to change pitch without changing tempo

2. Find a way to do it with ffmpeg

3. Find a way to do it directly in react-native. With only JavaScript.

4. Other react-native compatible libraries or suggestions

Here are some links that might help:

Lower/raise pitch with ffmpeg (here is the problem: I don't know what frequency it is at)

[login to view URL]

Audacitys implementation of change pitch without changing tempo

[login to view URL]

[login to view URL]

JavaScript implementation of changing pitch

[login to view URL]

I am grateful for any hints or suggestions!! Please only bid if you're 100% certain you can solve this challenge! And please remember I need this for react-native. Thanks alot!


Habilidades: Audio Processing, Mobile App Development, React Native, React.js, Sound Design

Veja mais: react-native-audio-toolkit npm, tone.js piano, react native audio editor, react-native-audio-toolkit, react native audio visualization, react native equalizer, react native audio api, react-native-audio-player-recorder, ffmpeg change movie audio mp3, project pitch frequency, create native library, java audio native library, change icon design mp3 player, write good native writer, write msg file library, change wimax frequency evo, android change wimax frequency, htc evo change center frequency, java jmf change pitch, ipod touch music change pitch

Acerca do Empregador:
( 0 comentários ) Laatzen, Germany

ID do Projeto: #18554410

4 freelancers estão ofertando em média $172 para esse trabalho


Dear employer! I read your project proposal carefully and I am sure I can perform this project perfectly. I have around 10 years of experience in Mobile app development and having 4 years of experience in ReactNative Mais

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I am a React Native Mobile application developer with experience in social apps. I have developed more that 15 apps in React Native from scratch and for clients across the globe, All of apps are live now on Google Pla Mais

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hello? how are you? i checked your project details carefully, so that i feel very confident in your project because i am talented mobile app developer with react native. If you give me all data for the project, I wil Mais

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