AudioClip.GetData

Description

Fills an array with sample data from the clip.

The sample data will contain float values within the range -1.0f to 1.0f. The sample count is determined by the length of the Span or float array. Use the offsetSamples parameter to start the read from a specific position in the clip. If the read length from the offset is longer than the clip length, the read will wrap around and read the remaining samples from the start of the clip.

With compressed audio files, the sample data can only be retrieved when the Load Type is set to Decompress on Load in the Audio Clip importer. GetData doesn't work with streamed audio clips, including clips streamed from the disk and clips created with AudioClip.Create where the stream parameter has been set to true. If GetData can't read the audio clip, the data argument will contain zeroes for all sample values, the console will log an error, and GetData will return false.

For best performance, the Span version is preferred as it does not require allocating managed memory.

using UnityEngine;
using Unity.Collections;

public class Example : MonoBehaviour
{
    // Read all the samples from the clip and halve the gain
    void Start()
    {
        AudioSource audioSource = GetComponent<AudioSource>();
        var numSamples = audioSource.clip.samples * audioSource.clip.channels;
        var samples = new NativeArray<float>(numSamples, Allocator.Temp);
        audioSource.clip.GetData(samples, 0);

        for (int i = 0; i < samples.Length; ++i)
        {
            samples[i] = samples[i] * 0.5f;
        }

        audioSource.clip.SetData(samples, 0);
    }
}

WebGL: The sample data of audio clips is loaded asynchronously in the WebGL platform. This makes it necessary to check the loadState of an AudioClip before reading the sample data.

using UnityEngine;
using Unity.Collections;
using System.Collections;

public class ExampleGetDataCoroutine : MonoBehaviour
{
    void Start()
    {
        StartCoroutine(GetAudioData());
    }

    IEnumerator GetAudioData()
    {
        AudioSource audioSource = GetComponent<AudioSource>();
        // Wait for sample data to be loaded
        while (audioSource.clip.loadState != AudioDataLoadState.Loaded)
        {
            yield return null;
        }

        // Read all the samples from the clip and halve the gain
        var numSamples = audioSource.clip.samples * audioSource.clip.channels;
        var samples = new NativeArray<float>(numSamples, Allocator.Temp);
        audioSource.clip.GetData(samples, 0);

        for (int i = 0; i < samples.Length; ++i)
        {
            samples[i] = samples[i] * 0.5f;
        }

        audioSource.clip.SetData(samples, 0);
    }
}