如何在Unity中更改音频采样率

Question

默认音频采样率为48000。是否可以将其更改为其他值，如44100？我记录了AudioSettings.outputSampleRate的值，它显示48000。但似乎不可能改变这个值。

Answer 1

以下是更改Unity音频剪辑采样率的代码：

1. 最简单，但非常粗糙
2. 平均方法，但渠道变得混杂
3. 每个通道的平均方法(最佳质量(

public static AudioClip SetSampleRateSimple(AudioClip clip, int frequency)
{
if (clip.frequency == frequency) return clip;
var samples = new float[clip.samples * clip.channels];
clip.GetData(samples, 0);
var samplesLength = (int)(frequency * clip.length) * clip.channels;
var samplesNew = new float[samplesLength];
var clipNew = AudioClip.Create(clip.name + "_" + frequency, samplesLength, clip.channels, frequency, false);
for (var i = 0; i < samplesLength; i++)
{
var index = (int) ((float) i * samples.Length / samplesLength);
samplesNew[i] = samples[index];
}
clipNew.SetData(samplesNew, 0);
return clipNew;
}

public static AudioClip SetSampleRateAverage(AudioClip clip, int frequency)
{
if (clip.frequency == frequency) return clip;
var samples = new float[clip.samples * clip.channels];
clip.GetData(samples, 0);
var samplesNewLength = (int) (frequency * clip.length) * clip.channels;
var samplesNew = new float[samplesNewLength];
var clipNew = AudioClip.Create(clip.name + "_" + frequency, samplesNewLength, clip.channels, frequency, false);
var index = 0;
var sum = 0f;
var count = 0;
for (var i = 0; i < samples.Length; i++)
{
var index_ = (int)((float)i / samples.Length * samplesNewLength);
if (index_ == index)
{
sum += samples[i];
count++;
}
else
{
samplesNew[index] = sum / count;
index = index_;
sum = samples[i];
count = 1;
}
}
clipNew.SetData(samplesNew, 0);
return clipNew;
}

public static AudioClip SetSampleRate(AudioClip clip, int frequency)
{
if (clip.frequency == frequency) return clip;
if (clip.channels != 1 && clip.channels != 2) return clip;
var samples = new float[clip.samples * clip.channels];
clip.GetData(samples, 0);
var samplesNewLength = (int) (frequency * clip.length) * clip.channels;
var clipNew = AudioClip.Create(clip.name + "_" + frequency, samplesNewLength, clip.channels, frequency, false);
var channelsOriginal = new List<float[]>();
var channelsNew = new List<float[]>();
if (clip.channels == 1)
{
channelsOriginal.Add(samples);
channelsNew.Add(new float[(int) (frequency * clip.length)]);
}
else
{
channelsOriginal.Add(new float[clip.samples]);
channelsOriginal.Add(new float[clip.samples]);
channelsNew.Add(new float[(int) (frequency * clip.length)]);
channelsNew.Add(new float[(int) (frequency * clip.length)]);
for (var i = 0; i < samples.Length; i++)
{
channelsOriginal[i % 2][i / 2] = samples[i];
}
}
for (var c = 0; c < clip.channels; c++)
{
var index = 0;
var sum = 0f;
var count = 0;
var channelSamples = channelsOriginal[c];
for (var i = 0; i < channelSamples.Length; i++)
{
var index_ = (int) ((float) i / channelSamples.Length * channelsNew[c].Length);
if (index_ == index)
{
sum += channelSamples[i];
count++;
}
else
{
channelsNew[c][index] = sum / count;
index = index_;
sum = channelSamples[i];
count = 1;
}
}
}
float[] samplesNew;
if (clip.channels == 1)
{
samplesNew = channelsNew[0];
}
else
{
samplesNew = new float[channelsNew[0].Length + channelsNew[1].Length];
for (var i = 0; i < samplesNew.Length; i++)
{
samplesNew[i] = channelsNew[i % 2][i / 2];
}
}
clipNew.SetData(samplesNew, 0);
return clipNew;
}