public string ReadIso639()
{
int bits = ReadUInt16();
StringBuilder result = new StringBuilder();
for (int i = 0; i < 3; i++)
{
int c = (bits >> (2 - i) * 5) & 0x1f;
result.Append((char)(c + 0x60));
}
return result.ToString();
}
public string Read4cc() => Encoding.GetEncoding("ISO-8859-1").GetString(ReadBytes(4));