private static PeakStore CreatePeakStore(AudioTrack audioTrack, bool fileSupport)
{
IAudioStream audioInputStream = audioTrack.CreateAudioStream();
PeakStore peakStore = new PeakStore(SAMPLES_PER_PEAK, audioInputStream.Properties.Channels,
(int)Math.Ceiling((float)audioInputStream.Length / audioInputStream.SampleBlockSize / SAMPLES_PER_PEAK));
Action peakStoreFillAction = delegate {
FillPeakStore(audioTrack, fileSupport, audioInputStream, peakStore);
audioInputStream.Close();
};
// add task
peakStoreQueue.Add(peakStoreFillAction);
// create consumer/worker threads
for (; peakStoreQueueThreads < Math.Min(2, Environment.ProcessorCount); peakStoreQueueThreads++)
{
Task.Factory.StartNew(() => {
// process peakstore actions as long as the queue is not empty
Debug.WriteLine("PeakStoreQueue thread started");
while (peakStoreQueue.Count > 0)
{
peakStoreQueue.Take().Invoke();
}
peakStoreQueueThreads--;
Debug.WriteLine("PeakStoreQueue thread stopped");
});
}
return(peakStore);
}
private static void FillPeakStore(AudioTrack audioTrack, bool fileSupport, IAudioStream audioInputStream, PeakStore peakStore)
{
bool peakFileLoaded = false;
// search for existing peakfile
if (audioTrack.HasPeakFile && fileSupport)
{
// load peakfile from disk
try {
peakStore.ReadFrom(File.OpenRead(audioTrack.PeakFile.FullName), audioTrack.FileInfo.LastWriteTimeUtc);
peakStore.CalculateScaledData(8, 6);
peakFileLoaded = true;
}
catch (Exception e) {
Console.WriteLine("peakfile read failed: " + e.Message);
}
}
// generate peakfile
if (!peakFileLoaded)
{
int channels = peakStore.Channels;
byte[] buffer = new byte[65536 * audioInputStream.SampleBlockSize];
float[] min = new float[channels];
float[] max = new float[channels];
BinaryWriter[] peakWriters = peakStore.CreateMemoryStreams().WrapWithBinaryWriters();
IProgressReporter progressReporter = ProgressMonitor.GlobalInstance.BeginTask("Generating peaks for " + audioTrack.Name, true);
DateTime startTime = DateTime.Now;
int sampleBlockCount = 0;
int peakCount = 0;
int bytesRead;
long totalSampleBlocks = audioInputStream.Length / audioInputStream.SampleBlockSize;
long totalSamplesRead = 0;
int progress = 0;
for (int i = 0; i < channels; i++)
{
min[i] = float.MaxValue;
max[i] = float.MinValue;
}
unsafe
{
fixed(byte *bufferB = &buffer[0])
{
float *bufferF = (float *)bufferB;
int samplesRead;
int samplesProcessed;
bool peakStoreFull = false;
while ((bytesRead = StreamUtil.ForceRead(audioInputStream, buffer, 0, buffer.Length)) > 0)
{
samplesRead = bytesRead / audioInputStream.Properties.SampleByteSize;
samplesProcessed = 0;
do
{
for (int channel = 0; channel < channels; channel++)
{
if (min[channel] > bufferF[samplesProcessed])
{
min[channel] = bufferF[samplesProcessed];
}
if (max[channel] < bufferF[samplesProcessed])
{
max[channel] = bufferF[samplesProcessed];
}
samplesProcessed++;
totalSamplesRead++;
}
if (++sampleBlockCount % SAMPLES_PER_PEAK == 0 || sampleBlockCount == totalSampleBlocks)
{
// write peak
peakCount++;
for (int channel = 0; channel < channels; channel++)
{
peakWriters[channel].Write(new Peak(min[channel], max[channel]));
// add last sample of previous peak as first sample of current peak to make consecutive peaks overlap
// this gives the impression of a continuous waveform
min[channel] = max[channel] = bufferF[samplesProcessed - channels];
}
//sampleBlockCount = 0;
}
if (sampleBlockCount == totalSampleBlocks && samplesProcessed < samplesRead)
{
// There's no more space for more peaks
// TODO how to handle this case? why is there still audio data left?
Console.WriteLine("peakstore full, but there are samples left ({0} < {1})", samplesProcessed, samplesRead);
peakStoreFull = true;
break;
}
}while (samplesProcessed < samplesRead);
progressReporter.ReportProgress(100.0f / audioInputStream.Length * audioInputStream.Position);
if ((int)(100.0f / audioInputStream.Length * audioInputStream.Position) > progress)
{
progress = (int)(100.0f / audioInputStream.Length * audioInputStream.Position);
peakStore.OnPeaksChanged();
}
if (peakStoreFull)
{
break;
}
}
}
}
Debug.WriteLine("generating downscaled peaks...");
peakStore.CalculateScaledData(8, 6);
Debug.WriteLine("peak generation finished - " + (DateTime.Now - startTime) + ", " + (peakWriters[0].BaseStream.Length * channels) + " bytes");
progressReporter.Finish();
if (fileSupport)
{
// write peakfile to disk
try {
FileStream peakOutputFile = File.OpenWrite(audioTrack.PeakFile.FullName);
peakStore.StoreTo(peakOutputFile, audioTrack.FileInfo.LastWriteTimeUtc);
peakOutputFile.Close();
}
catch (UnauthorizedAccessException e) {
Debug.WriteLine("peak file writing failed: " + e.Message);
}
}
}
peakStore.OnPeaksChanged();
}
