public DiscreteSignal GetSignal()
{
stopwatch.Restart();
// unique NoteSegments
Dictionary <(int Track, byte Channel, int DurationSamples, byte Note, byte Velocity), NoteSegment> noteSegmentsToRender = new Dictionary <(int Track, byte Channel, int DurationSamples, byte Note, byte Velocity), NoteSegment>();
// find unique note segments
foreach (var segment in Interpretation.NoteSegments)
{
// If the dictionary does not contain the segment's identifierr, add the segment
if (!noteSegmentsToRender.ContainsKey(segment.ReuseIdentifier))
{
noteSegmentsToRender[segment.ReuseIdentifier] = segment; // cache the first of a repeated signal
}
}
OnProgressChanged(new GenerationProgressChangedEventArgs(1, 5, "Duplicate note consolidation", stopwatch.Elapsed));
stopwatch.Restart();
int notesRendered = 0;
int totalToRender = noteSegmentsToRender.Count;
// unique DiscreteSignals
ConcurrentDictionary <(int Track, byte Channel, int DurationSamples, byte Note, byte Velocity), DiscreteSignal> signalCache = new ConcurrentDictionary <(int Track, byte Channel, int DurationSamples, byte Note, byte Velocity), DiscreteSignal>();
// generate unique signals in parallel
Parallel.ForEach(noteSegmentsToRender, segment =>
{
signalCache[segment.Value.ReuseIdentifier] = Render(segment.Value);
Interlocked.Increment(ref notesRendered);
OnProgressChanged(new NoteRenderedEventArguments(notesRendered, totalToRender, "Note rendered in parallel"));
});
OnProgressChanged(new GenerationProgressChangedEventArgs(2, 5, "Unique note rendering", stopwatch.Elapsed));
stopwatch.Restart();
float[] samples = new float[Interpretation.TotalDurationSamples];
// assemble the final wav
foreach (NoteSegment segment in Interpretation.NoteSegments)
{
DiscreteSignal segmentSignal = signalCache[segment.ReuseIdentifier];
long startSample = segment.StartSample;
for (long i = 0; i < segmentSignal.Samples.Length; i++)
{
samples[startSample + i] = samples[startSample + i] + segmentSignal.Samples[i]; // add the samples together
}
}
OnProgressChanged(new GenerationProgressChangedEventArgs(3, 5, "Wave assembly", stopwatch.Elapsed));
stopwatch.Restart();
DiscreteSignal signal = new DiscreteSignal(44100, samples);
signal.ScaleAmplitude(0.9f); // adjust the samples to fit between [-1, 1] (using a value of 1 sometimes seems to cause clipping)
OnProgressChanged(new GenerationProgressChangedEventArgs(4, 5, "Wave normalization", stopwatch.Elapsed));
stopwatch.Stop();
return(signal);
}
