public float[] getLevelAt(double seconds, double duration)
{
if (levelStream == 0 && File != "")
{
levelStream = Bass.BASS_StreamCreateFile(File, 0, 0, BASSFlag.BASS_STREAM_DECODE | BASSFlag.BASS_SAMPLE_FLOAT | BASSFlag.BASS_STREAM_PRESCAN);
if (levelStream == 0)
{
return(new float[2]);
}
}
Bass.BASS_ChannelSetPosition(levelStream, seconds);
float[] levels = new float[2];
return(Bass.BASS_ChannelGetLevels(levelStream, (float)duration, BASSLevel.BASS_LEVEL_STEREO));
}
private void waveformGenerateWorker_DoWork(object sender, DoWorkEventArgs e)
{
WaveformGenerationParams waveformParams = e.Argument as WaveformGenerationParams;
int stream = Bass.BASS_StreamCreateFile(waveformParams.Path, 0, 0, BASSFlag.BASS_STREAM_DECODE | BASSFlag.BASS_SAMPLE_FLOAT | BASSFlag.BASS_STREAM_PRESCAN);
int frameLength = (int)Bass.BASS_ChannelSeconds2Bytes(stream, 0.02);
long streamLength = Bass.BASS_ChannelGetLength(stream, 0);
int frameCount = (int)((double)streamLength / (double)frameLength);
int waveformLength = frameCount * 2;
float[] waveformData = new float[waveformLength];
float[] levels = new float[2];
int actualPoints = Math.Min(waveformParams.Points, frameCount);
int compressedPointCount = actualPoints * 2;
float[] waveformCompressedPoints = new float[compressedPointCount];
List <int> waveMaxPointIndexes = new List <int>();
for (int i = 1; i <= actualPoints; i++)
{
waveMaxPointIndexes.Add((int)Math.Round(waveformLength * ((double)i / (double)actualPoints), 0));
}
float maxLeftPointLevel = float.MinValue;
float maxRightPointLevel = float.MinValue;
int currentPointIndex = 0;
for (int i = 0; i < waveformLength; i += 2)
{
levels = Bass.BASS_ChannelGetLevels(stream);
waveformData[i] = levels[0];
waveformData[i + 1] = levels[1];
if (levels[0] > maxLeftPointLevel)
{
maxLeftPointLevel = levels[0];
}
if (levels[1] > maxRightPointLevel)
{
maxRightPointLevel = levels[1];
}
if (i > waveMaxPointIndexes[currentPointIndex])
{
waveformCompressedPoints[(currentPointIndex * 2)] = maxLeftPointLevel;
waveformCompressedPoints[(currentPointIndex * 2) + 1] = maxRightPointLevel;
maxLeftPointLevel = float.MinValue;
maxRightPointLevel = float.MinValue;
currentPointIndex++;
}
if (i % 3000 == 0)
{
float[] clonedData = (float[])waveformCompressedPoints.Clone();
Application.Current.Dispatcher.Invoke(new Action(() =>
{
WaveformData = clonedData;
}));
}
if (waveformGenerateWorker.CancellationPending)
{
e.Cancel = true;
break;
;
}
}
float[] finalClonedData = (float[])waveformCompressedPoints.Clone();
Application.Current.Dispatcher.Invoke(new Action(() =>
{
fullLevelData = waveformData;
WaveformData = finalClonedData;
}));
Bass.BASS_StreamFree(stream);
}