/// <param name="audioFormat">WavWriterLowLevel.WAVE_FORMAT_PCM or WavWriterLowLevel.WAVE_FORMAT_IEEE_FLOAT</param>
public static bool WriteRiffHeader(BinaryWriter bw,
int numChannels,
int bitsPerSample,
int audioFormat,
int sampleRate,
long sampleBytes)
{
int riffChunkBytes = 12;
int fmtChunkBytes = 26;
int dataChunkHeaderBytes = 8;
int padBytes = ((sampleBytes & 1) == 1) ? 1 : 0;
long fileBytes = riffChunkBytes + fmtChunkBytes + dataChunkHeaderBytes + sampleBytes + padBytes;
if (0xffffffffL < fileBytes)
{
System.Diagnostics.Debug.Assert(false);
return(false);
}
var wav = new WavWriterLowLevel();
wav.RiffChunkWrite(bw, (int)(fileBytes - 8));
wav.FmtChunkWriteEx(bw, (short)numChannels, sampleRate, (short)bitsPerSample, (short)audioFormat, 0);
wav.DataChunkHeaderWrite(bw, (int)sampleBytes);
return(true);
}
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;
}
