Wav转换与NAudio

Question

将常规wav转换为a-law声音时遇到问题。这样做时我的质量很差：

var image: UIImage? { 
    guard let url = try? FileManager.default.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: false).appendingPathComponent(self).appendingPathExtension("‌​png"), 
          let data = try? Data(contentsOf: url) else { return nil }
    return UIImage(data: data) 
}

或者说twise减慢声音：

WaveStream stream = new WaveFileReader(in.wav);
var s = new RawSourceWaveStream(new WaveFormatConversionStream(new WaveFormat(8000, 16, 1), stream), new WaveFormat(8000, 16, 1));
var c = new WaveFormatConversionStream(WaveFormat.CreateALawFormat(8000, 1), s);
WaveFileWriter.CreateWaveFile(AppDomain.CurrentDomain.BaseDirectory + "\\out.alaw", c);

如何将wav转换为高质量的a-law？

Answer 1

在任何一个示例中，您都不需要RawSourceStream，第二个示例将无效，除非in.wav恰好具有正确的格式。

试试这个：

var stream = new WaveFileReader(in.wav);
var s = new WaveFormatConversionStream(new WaveFormat(8000, 16, 1), stream);
var c = new WaveFormatConversionStream(WaveFormat.CreateALawFormat(8000, 1), s);
WaveFileWriter.CreateWaveFile(AppDomain.CurrentDomain.BaseDirectory + "\\out.alaw", c);