public static void EncodeWaveFile(string WaveIn, string BPCMOut, Parameters Parameters, dgUpdate StatusCallback = null, double UpdateInterval = 250, dgFrameEncoded FrameEncodedCallback = null)
{
using (FileStream streamIn = new FileStream(WaveIn, FileMode.Open, FileAccess.Read, FileShare.Read, 1048576, FileOptions.RandomAccess))
{
WAVEReader w = new WAVEReader(streamIn);
//Check parameters and if in doubt, set default ones
if (Parameters.BlockSize < 10)
{
Parameters.BlockSize = 10;
}
if (Parameters.BlockSize > 1000)
{
Parameters.BlockSize = 1000;
}
//Check if wFormatTag is 1 (PCM signed integer) and if not, crash!
if (w.Info.fmtHeader.wFormatTag != 1)
{
throw new Exception("BPCM 2.0 only supports PCM integer input (wFormatTag = 0x1)");
}
//Check if bits per sample is 16, if not crash!
if (w.Info.fmtHeader.nBitsPerSample != 16)
{
throw new Exception("BPCM 2.0 only supports 16 bit signed short integer input");
}
//Check if sampling rate is supported
if (!new uint[] { 48000, 44100, 32000, 24000 }.Contains(w.Info.fmtHeader.nSamplesPerSec))
{
throw new Exception("BPCM 2.0 only supports the sampling rates 48000, 44100, 32000 and 24000 Hz.");
}
//Check number of channels to be either mono or stereo
if (!new ushort[] { 1, 2 }.Contains(w.Info.fmtHeader.nChannels))
{
throw new Exception("BPCM 2.0 only supports mono or stereo source wave files.");
}
if (Parameters.SilenceThreshold == 0)
{
Parameters.SilenceThreshold = 4;
}
//Create BPCM output file stream
using (FileStream f = new FileStream(BPCMOut, FileMode.Create, FileAccess.Write, FileShare.Read, 1048576, FileOptions.SequentialScan))
{
//Data for the frame builder to use later
byte[] data = null;
byte compression = (byte)Parameters.Compression;
//Init ADPCM codec
ADPCM4BIT a = new ADPCM4BIT();
ADPCM4BIT_MONO am = new ADPCM4BIT_MONO();
//Stopwatch for the status callback
Stopwatch sw = new Stopwatch();
int currentFrame = 0;
long samplets = 0;
int silentSamples = 0;
double precisepos = 0;
TimeSpan pos;
sw.Start();
while (w.Position < streamIn.Length)
{
//Read the PCM data from the WAVE file, encode it with ADPCM and then wether requested compress it!
w.Read(out byte[] pcmBuffer, (uint)Parameters.BlockSize);
bool afterSilence = false;
byte[] compressedADPCM;
byte[] frame = new byte[0];
int nSamplesFromPCMBuffer;
int nSamplesSilent = 0;
int nSamplesFromMilliSeconds = (int)((Parameters.BlockSize / 1000.0) * w.Info.fmtHeader.nSamplesPerSec);
Compression.Compressed c = new Compression.Compressed();
Tunings.SilenceInfoBean silence_inf = Tunings.GetSilenceInfo(pcmBuffer, Parameters.SilenceThreshold);
switch (silence_inf.is_silent)
{
case Tunings.Silence.TotalSilence:
silentSamples += pcmBuffer.Length / ((w.Info.fmtHeader.nBitsPerSample / 8) * w.Info.fmtHeader.nChannels);
nSamplesSilent = silentSamples;
nSamplesFromPCMBuffer = silentSamples;
goto skip_write;
case Tunings.Silence.PartiallySilent:
case Tunings.Silence.FullSignal:
if (silence_inf.is_silent == Tunings.Silence.PartiallySilent &&
(silence_inf.silence_from == Tunings.SilenceAt.Beginning ||
silentSamples + silence_inf.buffer_pos / ((w.Info.fmtHeader.nBitsPerSample / 8) * w.Info.fmtHeader.nChannels) >= 16777215) &&
silentSamples > 0)
{
//We just have silence at the beginning of the frame, but pathway through there is signal
//Output a silent frame with extended length information
frame = Composer.ComposeFrame(null, (int)w.Info.fmtHeader.nSamplesPerSec, w.Info.fmtHeader.nChannels, InfoByte.CompressionType.None, true, (UInt32)silentSamples);
f.Write(frame, 0, frame.Length);
if (silentSamples != nSamplesFromMilliSeconds)
{
afterSilence = true;
}
else
{
afterSilence = false;
}
nSamplesSilent = silentSamples;
silentSamples = 0;
}
else
{
afterSilence = false;
}
//Prepare regular data
if (w.Info.fmtHeader.nChannels == 2)
{
compressedADPCM = a.encode(pcmBuffer, false);
}
else
{
compressedADPCM = am.encode(pcmBuffer);
}
c = Compression.Compress(compressedADPCM, Parameters.Compression);
data = c.data;
compression = (byte)c.usedAlgo;
break;
}
//Recalculate the blocksize when it differs from the setting, in example when the stream ends.
nSamplesFromPCMBuffer = (int)(pcmBuffer.LongLength / w.Info.fmtHeader.nChannels / (w.Info.fmtHeader.nBitsPerSample / 8));
nSamplesFromMilliSeconds = (int)((Parameters.BlockSize / 1000.0) * w.Info.fmtHeader.nSamplesPerSec);
frame = Composer.ComposeFrame(data, (int)w.Info.fmtHeader.nSamplesPerSec, w.Info.fmtHeader.nChannels, (InfoByte.CompressionType)compression, currentFrame == 0 || nSamplesFromPCMBuffer != nSamplesFromMilliSeconds || afterSilence, (UInt16)nSamplesFromPCMBuffer);
f.Write(frame, 0, frame.Length);
skip_write:
currentFrame++;
samplets = w.PCMPosition / w.Info.fmtHeader.nBlockAlign;
precisepos = (double)samplets / w.Info.fmtHeader.nSamplesPerSec;
pos = TimeSpan.FromSeconds(precisepos);
//Fire the frame encoded event
FrameEncodedCallback?.Invoke(new Stats()
{
FrameNumber = currentFrame
, TimeStamp = samplets
, FrameDuration = (nSamplesSilent > 0) ? nSamplesSilent / (double)w.Info.fmtHeader.nSamplesPerSec : nSamplesFromPCMBuffer / (double)w.Info.fmtHeader.nSamplesPerSec
, Bytes = frame.Length
, Bitrate = (int)Math.Round((double)frame.Length / (pcmBuffer.Length / w.Info.fmtHeader.nAvgBytesPerSeconds) * 8, 0)
, Compression = (Compression.Algorithm)compression
});
frame = null;
//Do the status callback after the interval has elapsed and reset the stopwatch
if (sw.ElapsedMilliseconds >= UpdateInterval || w.Position >= streamIn.Length)
{
StatusCallback?.Invoke(new Status()
{
FramesEncoded = currentFrame
, AvgBitrate = (int)Math.Round((f.Length / precisepos) * 8.0, 0)
, Position = precisepos
, PositionSamples = samplets
, PositionString = String.Format("{0:00}d {1:00}h {2:00}m {3:00}s {4:000.000}ms", pos.Days, pos.Hours, pos.Minutes, pos.Seconds, (precisepos - Math.Floor(precisepos)) * 1000)
, BytesWritten = f.Length
, Duration = w.Info.PCMDataLength / w.Info.fmtHeader.nAvgBytesPerSeconds
, DurationSamples = w.Info.PCMDataLength / w.Info.fmtHeader.nBlockAlign
});
sw.Restart();
}
}
//Check if silence was collected first and flush this as a silent frame before composing the current frame
if (silentSamples > 0)
{
byte[] frame = Composer.ComposeFrame(null, (int)w.Info.fmtHeader.nSamplesPerSec, w.Info.fmtHeader.nChannels, InfoByte.CompressionType.None, true, (UInt32)silentSamples);
f.Write(frame, 0, frame.Length);
}
}
}
}