小编Doo*_*Won的帖子

我正在尝试使用傅立叶系数创建声音。

首先请让我展示一下我是如何得到傅里叶系数的。

(1) 我对麦克风声音的波形进行了快照。

\n
• 获取麦克风：getUserMedia()
\n
• 获取麦克风声音：MediaStreamAudioSourceNode
\n
• 获取波形数据：AnalyserNode.getByteTimeDomainData()
\n

数据如下所示：（我将 Uint8Array 字符串化，它是 的返回值getByteTimeDomainData()，并添加length属性以便稍后将此对象更改为 Array）

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\xe2\x80\xbb 如果我们将这些数据绘制到画布上，我们可以看到以下内容：（这是元音“i”的声音（听起来像“ee”））

似乎捕获了 2 个周期的波。由于长度为512，我们可以猜测一个周期的数据位于索引0 ~ 255。

(2)我处理了数据。

const parsed = JSON.parse(raw);\nconst arrayfied = Array.from(parsed);\nconst sliced = arrayfied.slice(0, 256);\nconst refined = [];\n\n// According to the Web Audio API specification,\n// "The values stored in the unsigned byte array are computed in the following way.\n// Let x[k] …