protected virtual bool InitializeForWriting(Stream underlyingStream, WaveFormat2 wfIn, WaveFormat2 wfOut, bool fAppend)
{
if (fAppend)
{
long position = underlyingStream.Position;
underlyingStream.Seek(0, SeekOrigin.Begin);
LoadHeader();
_ckData.BeginWrite();
_ckData.Seek(position - _ckData.DataStart, SeekOrigin.Begin);
}
else
{
_baseStream.Position = 0;
_mmc = new RiffChunk(underlyingStream);
(_mmc as RiffChunk).BeginWrite();
_ckFmt = new FmtChunk(underlyingStream, wfOut);
_mmc.AppendChunk(_ckFmt);
_ckFmt.BeginWrite();
_ckFmt.Write(_ckFmt.WaveFormat.GetBytes());
_fmt = wfOut;
_ckData = new DataChunk(underlyingStream);
_mmc.AppendChunk(_ckData);
_ckData.BeginWrite();
}
return(true);
}
public override MMChunk CreateSubChunk(FourCC fourCC, Stream st)
{
MMChunk ck = base.CreateSubChunk(fourCC, st);
long size = 0;
foreach (MMChunk cck in m_chunkList)
{
if (cck != ck)
{
size += cck.Size;
}
}
ck.Start = m_posStart + 4 + size;
return(ck);
}
protected virtual void LoadHeader()
{
_mmc = MMChunk.FromStream(_baseStream);
_ckFmt = _mmc.FindChunk(FourCC.Fmt) as FmtChunk;
if (_ckFmt != null)
{
_fmt = _ckFmt.WaveFormat;
}
_ckData = _mmc.FindChunk(FourCC.Data) as DataChunk;
if (_ckData != null)
{
_posData = _ckData.DataStart;
}
_baseStream.Seek(_posData, SeekOrigin.Begin);
}
public override void LoadFromStream(Stream st)
{
byte[] data = new byte[4];
m_posStart = st.Position - 4;
st.Read(data, 0, 4);
m_nSize = BitConverter.ToInt32(data, 0);
st.Read(data, 0, 4);
if (Encoding.ASCII.GetString(data, 0, 4) != "WAVE")
{
throw new InvalidOperationException("Must have WAVE format");
}
while (st.Position - m_posStart != m_nSize + 8)
{
MMChunk ck = MMChunk.FromStream(st);
if (ck == null)
{
break;
}
m_chunkList.Add(ck);
}
}
public virtual void AppendChunk(MMChunk ck)
{
ck.m_fourCC.Write(_stm);
m_chunkList.Add(ck);
}