Virtu/Library/Silverlight/WaveMediaStreamSource.cs

77 lines
2.9 KiB
C#
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using System;
using System.Collections.Generic;
using System.IO;
using System.Windows.Media;
namespace Jellyfish.Library
{
public sealed class WaveMediaStreamSource : MediaStreamSource, IDisposable
{
public WaveMediaStreamSource(int sampleRate, int sampleChannels, int sampleBits, int sampleSize, int sampleLatency, Action<byte[], int> updater)
{
_bufferSize = sampleSize;
_buffer = new byte[_bufferSize];
_bufferStream = new MemoryStream(_buffer);
_waveFormat = new WaveFormat(sampleRate, sampleChannels, sampleBits);
AudioBufferLength = sampleLatency; // ms; avoids audio delay
_updater = updater;
}
public void Dispose()
{
_bufferStream.Dispose();
}
protected override void CloseMedia()
{
_audioDescription = null;
}
protected override void GetDiagnosticAsync(MediaStreamSourceDiagnosticKind diagnosticKind)
{
throw new NotImplementedException();
}
protected override void GetSampleAsync(MediaStreamType mediaStreamType)
{
_updater(_buffer, _bufferSize);
var sample = new MediaStreamSample(_audioDescription, _bufferStream, 0, _bufferSize, _timestamp, _emptySampleDict);
_timestamp += _bufferSize * 10000000L / _waveFormat.AverageBytesPerSec; // 100 ns
ReportGetSampleCompleted(sample);
}
protected override void OpenMediaAsync()
{
_timestamp = 0;
var sourceAttributes = new Dictionary<MediaSourceAttributesKeys, string>() { { MediaSourceAttributesKeys.Duration, "0" }, { MediaSourceAttributesKeys.CanSeek, "false" } };
var streamAttributes = new Dictionary<MediaStreamAttributeKeys, string>() { { MediaStreamAttributeKeys.CodecPrivateData, _waveFormat.ToHexString() } };
_audioDescription = new MediaStreamDescription(MediaStreamType.Audio, streamAttributes);
var availableStreams = new List<MediaStreamDescription>() { _audioDescription };
ReportOpenMediaCompleted(sourceAttributes, availableStreams);
}
protected override void SeekAsync(long seekToTime)
{
ReportSeekCompleted(seekToTime);
}
protected override void SwitchMediaStreamAsync(MediaStreamDescription mediaStreamDescription)
{
throw new NotImplementedException();
}
private byte[] _buffer;
private int _bufferSize;
private MemoryStream _bufferStream;
private Action<byte[], int> _updater;
private WaveFormat _waveFormat;
private long _timestamp;
private MediaStreamDescription _audioDescription;
private Dictionary<MediaSampleAttributeKeys, string> _emptySampleDict = new Dictionary<MediaSampleAttributeKeys, string>();
}
}