如何使用内存流、NAudio和LameMP3将音频aiff转换为MP3

Question

我尝试将一个音频文件从IFormFile转换为MP3，并将其上传到Azure Storage。我不明白NAudio的内存流是如何工作的.我不想复制临时文件中的文件，只想使用streams。有可能吗？

using (var retMs = new MemoryStream())
{
   file.CopyTo(retMs);
   var fileBytes = retMs.ToArray();
   string s = Convert.ToBase64String(fileBytes);

    using (var ms = new MemoryStream(fileBytes))
    using (var reader = new AiffFileReader(ms))
    using (var writer = new LameMP3FileWriter(retMs, reader.WaveFormat, 128))
    {
       reader.CopyTo(writer);

       var result = await _blobService.UploadFileBlobAsync(
                              reader,
                              "audio/mpeg3",
                              "fr2.mp3");

       toReturn = result.AbsoluteUri; 
      }
                                
   }

Answer 1

我认为下面的演示代码可能会对你有所帮助。

using Azure.Storage.Blobs;
using NAudio.Lame;
using NAudio.Wave;
using System;
using System.IO;

namespace blobUpload
{
    class Program
    {
        static void Main(string[] args)
        {
            string containerName = "<container name>";
            string blobName = "test.mp3";
            string storageConnStr = "<storage account conn str>";

            var blobServiceClient = new BlobServiceClient(storageConnStr);
            var blobClient = blobServiceClient.GetBlobContainerClient(containerName).GetBlobClient(blobName);

            using (var retMs = new MemoryStream())
            {
                FileStream inputfileStream = new FileStream(@"<aiff file path>", FileMode.Open, FileAccess.Read);
                inputfileStream.CopyTo(retMs);
                var fileBytes = retMs.ToArray();
                
                var bytes = ConvertWavToMp3(fileBytes);

                blobClient.UploadAsync(new MemoryStream(bytes)).GetAwaiter().GetResult();

            }

        }

        public static byte[] ConvertWavToMp3(byte[] wavFile)
        {

            using (var retMs = new MemoryStream())
            using (var ms = new MemoryStream(wavFile))
            using (var rdr = new AiffFileReader(ms))
            using (var wtr = new LameMP3FileWriter(retMs, rdr.WaveFormat, 128))
            {
                rdr.CopyTo(wtr);
                return retMs.ToArray();
            }

       }
    }

结果：

​

我已经在我这边测试过了，这个.MP3文件可以完美地播放。