private void AddTrack(AudioTrack audioTrack)
{
if (audioTrack.SourceProperties.SampleRate > audioMixer.SampleRate)
{
// The newly added track has a higher samplerate than the current tracks, so we adjust
// the processing samplerate to the highest rate
ChangeMixingSampleRate(audioTrack.SourceProperties.SampleRate);
}
IAudioStream input = audioTrack.CreateAudioStream();
IAudioStream baseStream = new TolerantStream(new BufferedStream(input, 1024 * 256 * input.SampleBlockSize, true));
OffsetStream offsetStream = new OffsetStream(baseStream)
{
Offset = TimeUtil.TimeSpanToBytes(audioTrack.Offset, baseStream.Properties)
};
audioTrack.OffsetChanged += new EventHandler <ValueEventArgs <TimeSpan> >(
delegate(object sender, ValueEventArgs <TimeSpan> e) {
offsetStream.Offset = TimeUtil.TimeSpanToBytes(e.Value, offsetStream.Properties);
audioMixer.UpdateLength();
});
// Upmix mono inputs to dual channel stereo to allow channel balancing
MonoStream stereoStream = new MonoStream(offsetStream, 2);
if (offsetStream.Properties.Channels > 1)
{
stereoStream.Downmix = false;
}
// control the track phase
PhaseInversionStream phaseInversion = new PhaseInversionStream(stereoStream)
{
Invert = audioTrack.InvertedPhase
};
MonoStream monoStream = new MonoStream(phaseInversion, phaseInversion.Properties.Channels)
{
Downmix = audioTrack.MonoDownmix
};
// necessary to control each track individually
VolumeControlStream volumeControl = new VolumeControlStream(monoStream)
{
Mute = audioTrack.Mute,
Volume = audioTrack.Volume,
Balance = audioTrack.Balance
};
// when the AudioTrack.Mute property changes, just set it accordingly on the audio stream
audioTrack.MuteChanged += new EventHandler <ValueEventArgs <bool> >(
delegate(object vsender, ValueEventArgs <bool> ve) {
volumeControl.Mute = ve.Value;
});
// when the AudioTrack.Solo property changes, we have to react in different ways:
audioTrack.SoloChanged += new EventHandler <ValueEventArgs <bool> >(
delegate(object vsender, ValueEventArgs <bool> ve) {
AudioTrack senderTrack = (AudioTrack)vsender;
bool isOtherTrackSoloed = false;
foreach (AudioTrack vaudioTrack in trackList)
{
if (vaudioTrack != senderTrack && vaudioTrack.Solo)
{
isOtherTrackSoloed = true;
break;
}
}
/* if there's at least one other track that is soloed, we set the mute property of
* the current track to the opposite of the solo property:
* - if the track is soloed, we unmute it
* - if the track is unsoloed, we mute it
*/
if (isOtherTrackSoloed)
{
senderTrack.Mute = !ve.Value;
}
/* if this is the only soloed track, we mute all other tracks
* if this track just got unsoloed, we unmute all other tracks
*/
else
{
foreach (AudioTrack vaudioTrack in trackList)
{
if (vaudioTrack != senderTrack && !vaudioTrack.Solo)
{
vaudioTrack.Mute = ve.Value;
}
}
}
});
// when the AudioTrack.Volume property changes, just set it accordingly on the audio stream
audioTrack.VolumeChanged += new EventHandler <ValueEventArgs <float> >(
delegate(object vsender, ValueEventArgs <float> ve) {
volumeControl.Volume = ve.Value;
});
audioTrack.BalanceChanged += new EventHandler <ValueEventArgs <float> >(
delegate(object vsender, ValueEventArgs <float> ve) {
volumeControl.Balance = ve.Value;
});
audioTrack.InvertedPhaseChanged += new EventHandler <ValueEventArgs <bool> >(
delegate(object vsender, ValueEventArgs <bool> ve) {
phaseInversion.Invert = ve.Value;
});
audioTrack.MonoDownmixChanged += new EventHandler <ValueEventArgs <bool> >(
delegate(object vsender, ValueEventArgs <bool> ve) {
monoStream.Downmix = ve.Value;
});
// adjust sample rate to mixer output rate
ResamplingStream resamplingStream = new ResamplingStream(volumeControl,
ResamplingQuality.Medium, audioMixer.Properties.SampleRate);
IAudioStream trackStream = resamplingStream;
if (trackStream.Properties.Channels == 1 && audioMixer.Properties.Channels > 1)
{
trackStream = new MonoStream(trackStream, audioMixer.Properties.Channels);
}
audioMixer.Add(trackStream);
trackListStreams.Add(audioTrack, trackStream);
}