从流生成波形

我需要根据多个音频文件（.wav / .mp3）生成波形。 我目前正在使用NAudio，但我遇到了一些问题。 我不能使用文件的路径，因为我不允许将文件上传到服务器，大多数浏览器阻止路径（安全原因），所以我的方法是使用流或内存流。 我发现这个项目做了非常相似的事情，但是如果没有文件的直接路径，我就无法让它工作。 这是我从用户那里获取文件的代码

[HttpPost] public ActionResult UploadAudioFile() { if (Request.Files.Count > 0) { List list = new List(); var supportedFileTypes = new[] { "audio/mp3", "audio/wav" }; foreach (string file in Request.Files) { var _file = Request.Files[file]; if (_file != null) { var contentType = _file.ContentType.ToLower(); if (supportedFileTypes.Contains(contentType)) { var s = _file.InputStream; var name = _file.FileName; var song = new MusicViewModel(); System.Drawing.Image img; if (contentType.Equals("audio/mp3")) { song = _musicRepo.GetMetaDataFromMp3File(s, name); img = _musicRepo.GenerateWaveForm(s); } else if (contentType.Equals("audio/wav")) { song = _musicRepo.GetMetaDataFromWavFile(s, name); img = _musicRepo.GenerateWaveForm(s); } if (song != null) { list.Add(song); } } else { return Json(new { isSuccess = false, errorMsg = "We only allow audio files of .mp3 or .wav format. You have attempted to upload a file with " + contentType + "." }); } } } return Json(new { isSuccess = true, musicList = list }); } return Json(new { isSuccess = false }); } 

然后在我的音乐库中使用GenerateWaveForm

 public Image GenerateWaveForm(Stream stream) { Image img = null; WaveFormRenderer wr = new WaveFormRenderer(); try { img = wr.Render(stream); } catch (Exception ex) { throw; } return img; } 

我正在按照这个类的方法，但我收到错误“不是WAVE文件 – 没有RIFF标题”。 这是我创建exception的类

 public Image Render(Stream stream) { int destBytesPerSample = 0; long samples; WaveStream readerStream = new WaveFileReader(stream); if (readerStream.WaveFormat.Encoding != WaveFormatEncoding.Pcm && readerStream.WaveFormat.Encoding != WaveFormatEncoding.IeeeFloat) { readerStream = WaveFormatConversionStream.CreatePcmStream(readerStream); readerStream = new BlockAlignReductionStream(readerStream); var sourceBytesPerSample = (readerStream.WaveFormat.BitsPerSample / 8) * readerStream.WaveFormat.Channels; SampleChannel sampleChannel = new SampleChannel(readerStream, false); destBytesPerSample = 4 * sampleChannel.WaveFormat.Channels; samples = destBytesPerSample * (readerStream.Length / sourceBytesPerSample); var peakProvider = getPeakProvider(); WaveFormRendererSettings settings = GetRendererSettings(); var samplesPerPixel = (int)(samples / settings.Width); var stepSize = settings.PixelsPerPeak + settings.SpacerPixels; //peakProvider.Init(reader, samplesPerPixel * stepSize); return Render(peakProvider, settings); } return null; } 

当我尝试在方法Render中的第3行中创建对象readerStream时发生exception