/// <summary>
/// Detect BPM rate of <paramref name="inFile"/> and adjust tempo
/// setting accordingly if necessary.
/// </summary>
private static void DetectBpm(WavInFile inFile, RunParameters parameters)
{
var bpm = BpmDetect <TSampleType, TLongSampleType> .NewInstance(inFile.GetNumChannels(), inFile.GetSampleRate());
var sampleBuffer = new TSampleType[BUFF_SIZE];
// detect bpm rate
Console.Error.Write("Detecting BPM rate...");
Console.Error.Flush();
int nChannels = inFile.GetNumChannels();
Debug.Assert(BUFF_SIZE % nChannels == 0);
// Process the 'inFile' in small blocks, repeat until whole file has
// been processed
while (inFile.Eof() == false)
{
// Read sample data from input file
int num = inFile.Read(sampleBuffer, BUFF_SIZE);
// Enter the new samples to the bpm analyzer class
int samples = num / nChannels;
bpm.InputSamples(sampleBuffer, samples);
}
// Now the whole song data has been analyzed. Read the resulting bpm.
float bpmValue = bpm.GetBpm();
Console.Error.WriteLine("Done!");
// rewind the file after bpm detection
inFile.Rewind();
if (bpmValue > 0)
{
Console.Error.WriteLine("Detected BPM rate {0:0.0}\n", bpmValue);
}
else
{
Console.Error.WriteLine("Couldn't detect BPM rate.\n");
return;
}
if (parameters.GoalBpm > 0)
{
// adjust tempo to given bpm
parameters.TempoDelta = (parameters.GoalBpm / bpmValue - 1.0f) * 100.0f;
Console.Error.WriteLine("The file will be converted to {0:0.0} BPM\n", parameters.GoalBpm);
}
}
/// <summary>
/// Processes the sound.
/// </summary>
private static void Process(SoundTouch <TSampleType, TLongSampleType> pSoundTouch, WavInFile inFile, WavOutFile outFile)
{
int nSamples;
var sampleBuffer = new TSampleType[BUFF_SIZE];
if ((inFile == null) || (outFile == null))
{
return; // nothing to do.
}
int nChannels = inFile.GetNumChannels();
Debug.Assert(nChannels > 0);
int buffSizeSamples = BUFF_SIZE / nChannels;
// Process samples read from the input file
while (!inFile.Eof())
{
// Read a chunk of samples from the input file
int num = inFile.Read(sampleBuffer, BUFF_SIZE);
nSamples = num / inFile.GetNumChannels();
// Feed the samples into SoundTouch processor
pSoundTouch.PutSamples(sampleBuffer, nSamples);
// Read ready samples from SoundTouch processor & write them output file.
// NOTES:
// - 'receiveSamples' doesn't necessarily return any samples at all
// during some rounds!
// - On the other hand, during some round 'receiveSamples' may have more
// ready samples than would fit into 'sampleBuffer', and for this reason
// the 'receiveSamples' call is iterated for as many times as it
// outputs samples.
do
{
nSamples = pSoundTouch.ReceiveSamples(sampleBuffer, buffSizeSamples);
outFile.Write(sampleBuffer, nSamples * nChannels);
} while (nSamples != 0);
}
// Now the input file is processed, yet 'flush' few last samples that are
// hiding in the SoundTouch's internal processing pipeline.
pSoundTouch.Flush();
do
{
nSamples = pSoundTouch.ReceiveSamples(sampleBuffer, buffSizeSamples);
outFile.Write(sampleBuffer, nSamples * nChannels);
} while (nSamples != 0);
}
