void BwDoWork(object sender, DoWorkEventArgs e)
{
var args = e.Argument as BackgroundWorkerArgs;
e.Result = args;
short nCh = 1;
int sampleFreq = 44100;
int sineFreq = sampleFreq / 4;
long nPeriod = (long)(args.durationSec * sineFreq);
long nFrames = nPeriod * 4;
long nFrameBytes = nFrames * nCh * 4; // 8==sizeof float
if (0x7fff0000 < nFrameBytes)
{
args.errMsg = "Error: Sound Duration is too long!";
}
try {
using (var bw = new BinaryWriter(File.Open(args.path, FileMode.Create))) {
var wwl = new WavWriterLowLevel();
int dataChunkSize = (int)(nFrameBytes);
int riffChunkSize = 4 /* RIFF */
+ 26 /* fmt */
+ 8 /* DATA */
+ dataChunkSize;
wwl.RiffChunkWrite(bw, riffChunkSize);
wwl.FmtChunkWriteEx(bw, nCh, sampleFreq, 32, WavWriterLowLevel.WAVE_FORMAT_IEEE_FLOAT, 0);
wwl.DataChunkHeaderWrite(bw, dataChunkSize);
for (int i = 0; i < nPeriod; ++i)
{
var signal = new float[] {
0.0f,
+(float)Math.Pow(10, args.magnitude / 20.0),
0.0f,
-(float)Math.Pow(10, args.magnitude / 20.0),
};
bw.Write(signal[0]);
bw.Write(signal[1]);
bw.Write(signal[2]);
bw.Write(signal[3]);
}
}
} catch (System.Exception ex) {
args.errMsg = ex.ToString();
}
args.errMsg = "";
}
public static bool WriteWav(BinaryWriter bw, PcmData pcm, List <WavChunkParams> wavParamList)
{
var writer = new WavWriterLowLevel();
bool isDs64 = wavParamList.Find((WavChunkParams p) => { return(p.ChunkType == WavChunkType.DS64); }) != null;
long posDS64 = -1;
long posRiff = -1;
foreach (var i in wavParamList)
{
switch (i.ChunkType)
{
case WavChunkType.RIFF: {
// 仮。ファイルサイズが決まった時に書き直す。
posRiff = bw.BaseStream.Position;
writer.RiffChunkWrite(bw, -1);
}
break;
case WavChunkType.fmt: {
var fmt = i as FmtChunkParams;
switch (fmt.StructType)
{
case FmtChunkParams.WaveFormatStructType.WaveFormat:
writer.FmtChunkWrite(bw, (short)pcm.NumChannels, (int)pcm.SampleRate, (short)pcm.BitsPerSample);
break;
case FmtChunkParams.WaveFormatStructType.WaveFormatEx:
writer.FmtChunkWriteEx(bw, (short)pcm.NumChannels, (int)pcm.SampleRate,
(short)pcm.BitsPerSample,
pcm.SampleValueRepresentationType == PcmData.ValueRepresentationType.SFloat ? WavWriterLowLevel.WAVE_FORMAT_IEEE_FLOAT : WavWriterLowLevel.WAVE_FORMAT_PCM,
(short)fmt.CbSize);
break;
case FmtChunkParams.WaveFormatStructType.WaveFormatExtensible: {
int dwChannelMask = 0;
if (pcm.NumChannels == 2)
{
dwChannelMask = 3;
}
writer.FmtChunkWriteExtensible(bw, (short)pcm.NumChannels, (int)pcm.SampleRate,
(short)pcm.BitsPerSample, (short)pcm.ValidBitsPerSample,
pcm.SampleValueRepresentationType, (int)dwChannelMask);
}
break;
default:
System.Diagnostics.Debug.Assert(false);
break;
}
}
break;
case WavChunkType.DATA: {
var data = i as DataChunkParams;
long posDataStart = bw.BaseStream.Position;
writer.DataChunkWrite(bw, isDs64, pcm.GetSampleArray());
if (!isDs64 && 0 < data.ExtraChunkBytes)
{
// 実際よりも長いチャンクサイズを書き込む。
long posDataEnd = bw.BaseStream.Position;
bw.BaseStream.Seek(posDataStart + 4, SeekOrigin.Begin);
int chunkSize = pcm.GetSampleArray().Length + data.ExtraChunkBytes;
bw.Write(chunkSize);
bw.BaseStream.Seek(posDataEnd, SeekOrigin.Begin);
}
}
break;
case WavChunkType.JUNK: {
var junk = i as JunkChunkParams;
writer.JunkChunkWrite(bw, (ushort)junk.ContentBytes);
}
break;
case WavChunkType.bext: {
var bext = i as BextChunkParams;
writer.BextChunkWrite(bw, bext.Description, bext.Originator, bext.OriginatorReference,
bext.OriginationDate, bext.OriginationTime, bext.TimeReference, null, 0,
0, 0, 0, 0, null);
}
break;
case WavChunkType.DS64: {
posDS64 = bw.BaseStream.Position;
var ds64 = i as DS64ChunkParams;
writer.Ds64ChunkWrite(bw, ds64.RiffSize, ds64.DataSize, ds64.SampleCount);
}
break;
case WavChunkType.ID3: {
var id3 = i as ID3ChunkParams;
writer.ID3ChunkWrite(bw, id3.Title, id3.Album, id3.Artists, id3.AlbumCoverArt, id3.AlbumCoverArtMimeType);
}
break;
}
}
long posEnd = bw.BaseStream.Position;
RiffChunkParams riff = wavParamList.Find((WavChunkParams p) => { return(p.ChunkType == WavChunkType.RIFF); }) as RiffChunkParams;
if (!isDs64)
{
// RIFFのサイズが決まったので書き込む
int riffSize = (int)(posEnd - posRiff - 8);
riffSize += riff.ExtraChunkBytes;
bw.BaseStream.Seek(posRiff, SeekOrigin.Begin);
writer.RiffChunkWrite(bw, riffSize);
bw.BaseStream.Seek(posEnd, SeekOrigin.Begin);
}
else
{
// DS64のサイズが決まったので書き込む
DataChunkParams dcp = wavParamList.Find((WavChunkParams p) => { return(p.ChunkType == WavChunkType.DATA); }) as DataChunkParams;
long riffSize = posEnd - posRiff - 8;
riffSize += riff.ExtraChunkBytes;
long dataSize = pcm.GetSampleArray().LongLength;
if (0 < dcp.ExtraChunkBytes)
{
dataSize += dcp.ExtraChunkBytes;
}
long sampleCount = pcm.NumFrames;
bw.BaseStream.Seek(posDS64, SeekOrigin.Begin);
writer.Ds64ChunkWrite(bw, riffSize, dataSize, sampleCount);
bw.BaseStream.Seek(posEnd, SeekOrigin.Begin);
}
if (0 < riff.GarbageBytes)
{
// ファイルの最後にごみを書き込む
var zeroes = new byte[riff.GarbageBytes];
bw.Write(zeroes);
}
return(true);
}
