/// <summary>
/// Data Chunk
/// </summary>
private static void LoadDataChunk(WaveRIFF w, BinaryReader br, string fmt, UInt32 sz)
{
w.dataChunkHeader = fmt;
w.dataSize = sz;
Debug.Assert(w.bitsPerSample == 16); // 16-bit sample only
UInt32 sample_count = w.dataSize / 2;
w.data = new Int16[sample_count];
for (int i = 0; i < sample_count; ++i)
{
w.data[i] = br.ReadInt16();
}
}
/// <summary>
/// Fmt Chunk
/// </summary>
private static void LoadFmtChunk(WaveRIFF w, BinaryReader br, string fmt, UInt32 sz)
{
w.fmtChunkMarker = fmt;
w.lengthOfFmt = sz;
w.formatType = br.ReadUInt16();
//Debug.Log($"w.formatType:{w.formatType}");
w.channels = br.ReadUInt16();
//Debug.Log($"w.channels:{w.channels}");
w.sampleRate = br.ReadUInt32();
//Debug.Log($"w.sampleRate:{w.sampleRate}");
w.byteRate = br.ReadUInt32();
//Debug.Log($"w.byteRate:{w.byteRate}");
w.blockAlign = br.ReadUInt16();
//Debug.Log($"w.blockAlign:{w.blockAlign}");
w.bitsPerSample = br.ReadUInt16();
//Debug.Log($"w.bitsPerSample:{w.bitsPerSample}");
}
/// <summary>
/// Waveファイルのバイト列を解析
/// </summary>
public static WaveRIFF Load(byte[] binary)
{
WaveRIFF w = new WaveRIFF();
using (var ms = new MemoryStream(binary))
using (var br = new BinaryReader(ms))
{
w.riff = br.ReadUTF8String(4);
if (w.riff != "RIFF")
{
return(null);
}
//Debug.Log($"w.riff:{w.riff}");
w.overallSize = br.ReadUInt32();
//Debug.Log($"w.overallSize:{w.overallSize}");
w.wave = br.ReadUTF8String(4);
//Debug.Log($"w.wave:{w.wave}");
while (br.EOF() == false)
{
string chunk_marker = br.ReadUTF8String(4);
//Debug.Log($"chunk_marker:{chunk_marker}");
UInt32 chunk_length = br.ReadUInt32();
//Debug.Log($"chunk_length:{chunk_length}");
if (chunk_marker == "fmt ")
{
LoadFmtChunk(w, br, chunk_marker, chunk_length);
}
else if (chunk_marker == "data")
{
LoadDataChunk(w, br, chunk_marker, chunk_length);
}
else
{
//Debug.Log($"IgnoreChunk marker:{chunk_marker} length:{chunk_length}");
br.ReadBytes((int)chunk_length);
}
}
}
return(w);
}
