小编Jak*_*kub的帖子

我正试图从AVAudioPCMBufferSwift中生成一个谱图.我安装了一个tap AVAudioMixerNode并接收带有音频缓冲区的回调.我想将缓冲区中的信号转换为[Float:Float]字典,其中键表示频率,值表示相应频率上的音频幅度.

我尝试使用Apple的Accelerate框架,但我得到的结果似乎很可疑.我确定这只是我转换信号的方式.

我查看了这篇博客文章以供参考.

这是我有的:

self.audioEngine.mainMixerNode.installTapOnBus(0, bufferSize: 1024, format: nil, block: { buffer, when in
    let bufferSize: Int = Int(buffer.frameLength)

    // Set up the transform
    let log2n = UInt(round(log2(Double(bufferSize))))
    let fftSetup = vDSP_create_fftsetup(log2n, Int32(kFFTRadix2))

    // Create the complex split value to hold the output of the transform
    var realp = [Float](count: bufferSize/2, repeatedValue: 0)
    var imagp = [Float](count: bufferSize/2, repeatedValue: 0)
    var output = DSPSplitComplex(realp: &realp, imagp: &imagp)

    // Now I need to …