C# MP3 伴奏

使用建议：

参数调节指南：
- 低频人声残留：降低CenterFrequency(800-1500Hz)
- 高频人声残留：提高CenterFrequency(2500-3500Hz)
- 消除力度不足：提高EliminationStrength(0.9-1.0)
- 伴奏失真：降低EliminationStrength(0.7-0.9) 并提高GainCompensation(1.3-1.5)

using System;
using System.IO;
using NAudio.Wave;
using NAudio.Lame;public class AudioConverter
{public event EventHandler<int> ProgressChanged;public event EventHandler ConversionCompleted;public float EliminationStrength { get; set; } = 0.95f;    // 消除强度 0-1public void ConvertToAccompaniment(string inputPath, string outputPath){try{if (!File.Exists(inputPath)){throw new FileNotFoundException($"输入文件未找到: {inputPath}");}using (var mp3Reader = new Mp3FileReader(inputPath)){var sampleProvider = mp3Reader.ToSampleProvider();var originalFormat = sampleProvider.WaveFormat;if (originalFormat.Channels != 2){throw new InvalidOperationException("仅支持立体声音频文件");}// 创建16位PCM格式var pcm16Format = new WaveFormat(originalFormat.SampleRate, 16, originalFormat.Channels);long totalBytes = mp3Reader.Length;long processedBytes = 0;using (var pcmMemoryStream = new MemoryStream()){WaveFileWriter wavWriter = null;try{wavWriter = new WaveFileWriter(new IgnoreDisposeStream(pcmMemoryStream), pcm16Format);float[] buffer = new float[originalFormat.SampleRate * originalFormat.Channels];int samplesRead;while ((samplesRead = sampleProvider.Read(buffer, 0, buffer.Length)) > 0){ProcessVocalRemoval(buffer, samplesRead);// 将浮点数组转换为16位PCM字节数组byte[] pcm16Bytes = new byte[samplesRead * 2]; // 每个样本占2字节for (int i = 0; i < samplesRead; i++){// 钳制值并转换为16位整数float sample = Math.Max(-1.0f, Math.Min(1.0f, buffer[i]));short pcmSample = (short)(sample * short.MaxValue);pcm16Bytes[i * 2] = (byte)(pcmSample);pcm16Bytes[i * 2 + 1] = (byte)(pcmSample >> 8);}wavWriter.Write(pcm16Bytes, 0, pcm16Bytes.Length);processedBytes += pcm16Bytes.Length;// 计算进度时可能需要调整总长度，此处假设totalBytes为PCM数据估算长度int percent = (int)((double)processedBytes / (totalBytes * 2) * 100);ProgressChanged?.Invoke(this, percent);}}finally{wavWriter?.Dispose();}pcmMemoryStream.Position = 0;// 使用16位PCM格式初始化LAME编码器using (var mp3Writer = new LameMP3FileWriter(outputPath, pcm16Format, LAMEPreset.VBR_90)){pcmMemoryStream.CopyTo(mp3Writer);}}ProgressChanged?.Invoke(this, 100);ConversionCompleted?.Invoke(this, EventArgs.Empty);}}catch (FileNotFoundException ex){Console.WriteLine($"文件未找到: {ex.FileName}");}catch (InvalidOperationException ex){Console.WriteLine($"处理错误: {ex.Message}");}catch (Exception ex){Console.WriteLine($"发生未知错误: {ex.Message}");}}private void ProcessVocalRemoval(float[] buffer, int samplesRead){for (int i = 0; i < samplesRead; i += 2){float left = buffer[i];float right = buffer[i + 1];float difference = (left - right) * EliminationStrength;buffer[i] = difference;buffer[i + 1] = difference;}}// 修正4：添加流包装器防止WaveFileWriter关闭底层流private class IgnoreDisposeStream : Stream{private readonly Stream _baseStream;public IgnoreDisposeStream(Stream baseStream) => _baseStream = baseStream;public override bool CanRead => _baseStream.CanRead;public override bool CanSeek => _baseStream.CanSeek;public override bool CanWrite => _baseStream.CanWrite;public override long Length => _baseStream.Length;public override long Position{get => _baseStream.Position;set => _baseStream.Position = value;}public override void Flush() => _baseStream.Flush();public override int Read(byte[] buffer, int offset, int count) => _baseStream.Read(buffer, offset, count);public override long Seek(long offset, SeekOrigin origin) => _baseStream.Seek(offset, origin);public override void SetLength(long value) => _baseStream.SetLength(value);public override void Write(byte[] buffer, int offset, int count) => _baseStream.Write(buffer, offset, count);protected override void Dispose(bool disposing){// 不关闭底层流}}
}

效果对比表：

参数组合	适用场景	副作用
Strength=0.9, Freq=1500	清晰人声消除	可能损失部分低频伴奏
Strength=0.8, Freq=2500	保留贝斯/鼓点	高频人声可能有残留
Strength=1.0, Freq=800	消除低沉男声	可能产生金属感失真

注意事项：