public static EffectDefinition CreateAudioEnvelope(double volumePercent, double fadeInDuration,
double fadeOutDuration, double duration)
{
if ((volumePercent < 0) || (volumePercent > 1))
{
throw new SplicerException("Volume percentage must be between 0 and 1");
}
if ((fadeInDuration + fadeOutDuration) > duration)
{
throw new SplicerException(
"Sum of the fade-in and fade-out durations must not exceed the total duration");
}
string volumeValue = volumePercent.ToString(CultureInfo.InvariantCulture);
var definition = new EffectDefinition(AudioMixerEffect);
var volumeParameter = new Parameter();
volumeParameter.Name = "Vol";
if (fadeInDuration > 0)
{
volumeParameter.Value = "0";
volumeParameter.Intervals.Add(new Interval(fadeInDuration, volumeValue));
}
else
{
volumeParameter.Value = volumeValue;
}
if (fadeOutDuration > 0)
{
volumeParameter.Intervals.Add(new Interval(duration - (fadeInDuration + fadeOutDuration), volumeValue));
volumeParameter.Intervals.Add(new Interval(duration, "0"));
}
else
{
volumeParameter.Intervals.Add(new Interval(duration, volumeValue));
}
definition.Parameters.Add(volumeParameter);
return definition;
}
public void JumpVolume()
{
// and audible demonstration of the difference between interpolating
// parameter values for an effect, and jumping directly to them.
string outputFile = "JumpVolume.wma";
using (ITimeline timeline = new DefaultTimeline())
{
IGroup group = timeline.AddAudioGroup();
ITrack track = group.AddTrack();
IClip clip = track.AddClip("testinput.mp3", GroupMediaType.Audio, InsertPosition.Relative, 0, 0, 10);
var effectDefinition = new EffectDefinition(StandardEffects.AudioMixerEffect);
var volumeParameter = new Parameter("Vol", 0.0, 2, 1.0);
volumeParameter.Intervals.Add(new Interval(IntervalMode.Jump, 2.5, "0.2"));
volumeParameter.Intervals.Add(new Interval(IntervalMode.Jump, 3.5, "0.8"));
volumeParameter.Intervals.Add(new Interval(IntervalMode.Jump, 4.5, "0.2"));
volumeParameter.Intervals.Add(new Interval(IntervalMode.Jump, 5, "1.0"));
volumeParameter.Intervals.Add(new Interval(IntervalMode.Interpolate, clip.Duration, "0.0"));
effectDefinition.Parameters.Add(volumeParameter);
clip.AddEffect(0, clip.Duration, effectDefinition);
using (
var renderer =
new WindowsMediaRenderer(timeline, outputFile, WindowsMediaProfiles.MediumQualityAudio))
{
renderer.Render();
}
}
}