find frequencies from audio file in javascript

index.tsx
// create an AudioContext
const audioContext = new AudioContext();

// load the audio file into a buffer
fetch('audiofile.wav')
  .then(response => response.arrayBuffer())
  .then(arrayBuffer => audioContext.decodeAudioData(arrayBuffer))
  .then(audioBuffer => {
    
    // create an AnalyserNode
    const analyserNode = audioContext.createAnalyser();
    analyserNode.fftSize = 2048;
    
    // connect the AudioBufferSourceNode to the AnalyserNode
    const sourceNode = audioContext.createBufferSource();
    sourceNode.buffer = audioBuffer;
    sourceNode.connect(analyserNode);
    analyserNode.connect(audioContext.destination);
    
    // get the frequency data from the AnalyserNode
    const frequencyData = new Float32Array(analyserNode.frequencyBinCount);
    analyserNode.getFloatFrequencyData(frequencyData);

    // analyze the frequency data to find the dominant frequency
    const maxFrequencyIndex = frequencyData.indexOf(Math.max(...frequencyData));
    const dominantFrequency = audioContext.sampleRate * maxFrequencyIndex / frequencyData.length;

    console.log(`The dominant frequency is ${dominantFrequency} Hz`);
  });
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