Files
stream-shorts/src/StreamShorts.Library/Media/NAudioService.cs
T

87 lines
2.4 KiB
C#

using NAudio.Wave;
namespace StreamShorts.Library.Media;
/// <summary>
/// Represents a service for processing audio files using NAudio.
/// </summary>
/// <inheritdoc/>
internal sealed class NAudioService : IAudioService
{
public Stream ConvertMp3ToWav16(Stream mp3)
{
return UseStream(mp3, stream =>
{
using var reader = new Mp3FileReader(mp3);
var outFormat = new WaveFormat(16000, reader.WaveFormat.Channels);
using var resampler = new MediaFoundationResampler(reader, outFormat);
var waveStream = new MemoryStream();
WaveFileWriter.WriteWavFileToStream(waveStream, resampler);
waveStream.Position = 0;
return waveStream;
});
}
public int GetNumberOfWavSegments(Stream wavStream, TimeSpan segmentDuration)
{
return UseStream(wavStream, stream =>
{
using var waveReader = new WaveFileReader(wavStream);
var totalDuration = waveReader.TotalTime;
var segmentCount = (int)Math.Ceiling(totalDuration.TotalMilliseconds / segmentDuration.TotalMilliseconds);
return segmentCount;
});
}
public Stream GetWavSegment(Stream wavStream, int segmentNumber, TimeSpan segmentDuration)
{
return UseStream(wavStream, stream =>
{
using var segmentWaveReader = new WaveFileReader(wavStream);
var segment = segmentWaveReader.ToSampleProvider()
.Skip(segmentNumber * segmentDuration)
.Take(segmentDuration);
var segmentProvider = segment.ToWaveProvider16();
var segmentStream = new MemoryStream();
WaveFileWriter.WriteWavFileToStream(segmentStream, segmentProvider);
segmentStream.Position = 0;
return segmentStream;
});
}
private static T UseStream<T>(Stream stream, Func<Stream, T> action)
{
ValidateStream(stream);
var originalPosition = stream.Position;
try
{
stream.Position = 0;
return action(stream);
}
finally
{
stream.Position = originalPosition;
}
}
private static void ValidateStream(Stream stream)
{
if (stream == null)
{
throw new ArgumentNullException(nameof(stream), $"{nameof(stream)} cannot be null");
}
if (stream.CanRead is false)
{
throw new ArgumentException($"{nameof(stream)} must be readable", nameof(stream));
}
if (stream.CanSeek is false)
{
throw new ArgumentException($"{nameof(stream)} must be seekable", nameof(stream));
}
}
}