Version: 2022.3
LanguageEnglish
  • C#

AudioSource.GetSpectrumData

Suggest a change

Success!

Thank you for helping us improve the quality of Unity Documentation. Although we cannot accept all submissions, we do read each suggested change from our users and will make updates where applicable.

Close

Submission failed

For some reason your suggested change could not be submitted. Please <a>try again</a> in a few minutes. And thank you for taking the time to help us improve the quality of Unity Documentation.

Close

Cancel

Switch to Manual

Declaration

public void GetSpectrumData(float[] samples, int channel, FFTWindow window);

Parameters

samples The array to populate with audio samples. Its length must be a power of 2.
channel The channel to sample from.
window The FFTWindow type to use when sampling.

Description

Provides a block of the currently playing audio source's spectrum data.

The array given in the samples parameter will be filled with the requested data.

Number of values (the length of the samples array provided) must be a power of 2. (ie 128/256/512 etc). Min = 64. Max = 8192. Use window to reduce leakage between frequency bins/bands. Note, the more complex window type, the better the quality, but reduced speed.

This function will use the sampling rate specified in AudioSettings.outputSampleRate, and NOT the sampling rate specified for the audio clip.

Additional resources: AudioSource.GetOutputData, AudioListener.GetSpectrumData, AudioListener.GetOutputData.

using UnityEngine;

[RequireComponent(typeof(AudioSource))] public class AudioSourceGetSpectrumDataExample : MonoBehaviour { AudioSource m_MyAudioSource;

void Start() { m_MyAudioSource = GetComponent<AudioSource>(); } void Update() { float[] spectrum = new float[256];

m_MyAudioSource.GetSpectrumData(spectrum, 0, FFTWindow.Rectangular);

for (int i = 1; i < spectrum.Length - 1; i++) { Debug.DrawLine(new Vector3(i - 1, spectrum[i] + 10, 0), new Vector3(i, spectrum[i + 1] + 10, 0), Color.red); Debug.DrawLine(new Vector3(i - 1, Mathf.Log(spectrum[i - 1]) + 10, 2), new Vector3(i, Mathf.Log(spectrum[i]) + 10, 2), Color.cyan); Debug.DrawLine(new Vector3(Mathf.Log(i - 1), spectrum[i - 1] - 10, 1), new Vector3(Mathf.Log(i), spectrum[i] - 10, 1), Color.green); Debug.DrawLine(new Vector3(Mathf.Log(i - 1), Mathf.Log(spectrum[i - 1]), 3), new Vector3(Mathf.Log(i), Mathf.Log(spectrum[i]), 3), Color.blue); } } }

Obsolete GetSpectrumData returning a float[] is deprecated, use GetSpectrumData and pass a pre allocated array instead.

Declaration

public float[] GetSpectrumData(int numSamples, int channel, FFTWindow window);

Parameters

numSamples The number of samples to retrieve. Must be a power of 2.
channel The channel to sample from.
window The FFTWindow type to use when sampling.

Description

Deprecated Version. Returns a block of the currently playing source's spectrum data.

This variation of the function allocates a new array each time it is called. Use the Non-alloc version instead for better performance.

Number of values (numSamples) must be a power of 2. (ie 128/256/512 etc). Min = 64. Max = 8192. Use window to reduce leakage between frequency bins/bands. Note, the more complex window type, the better the quality, but reduced speed.