private bool ReadChunk(FileStream fs)
{
if (fs.Position == fs.Length)
{
return(false);
}
Sanity.Requires(fs.Position + 8 <= fs.Length, "Broken header");
string header = GetString(fs, 4);
int chunkSize = GetInt(fs);
Sanity.Requires(fs.Position + chunkSize <= fs.Length, "Broken chunk.");
switch (header)
{
case "fmt ":
FormatChunk = new byte[chunkSize];
fs.Read(FormatChunk, 0, chunkSize);
break;
case "data":
DataLength = chunkSize;
fs.Seek(chunkSize, SeekOrigin.Current);
break;
default:
fs.Seek(chunkSize, SeekOrigin.Current);
break;
}
return(true);
}
private void PostCheck()
{
Sanity.Requires(FormatChunk != null, "Missing format chunk.");
Sanity.Requires(FormatChunk.Length >= 16, "Broken format chunk.");
Sanity.Requires(DataLength >= 0, "Missing data chunk.");
SampleRate = BitConverter.ToInt32(FormatChunk, 4);
ByteRate = BitConverter.ToInt32(FormatChunk, 8);
AudioLength = (double)DataLength / ByteRate;
}
public void Load(string wavPath)
{
using (FileStream fs = new FileStream(wavPath, FileMode.Open, FileAccess.Read))
{
Sanity.Requires(fs.Length >= 44, $"Invalid wave file, length is {fs.Length}.");
Sanity.Requires(GetString(fs, 4) == "RIFF", "Expected RIFF header.");
int riffLength = GetInt(fs);
Sanity.Requires(riffLength + 8 == fs.Length, "Broken RIFF chunk.");
Sanity.Requires(GetString(fs, 4) == "WAVE", "Expected WAVE header.");
while (ReadChunk(fs))
{
;
}
PostCheck();
}
}