public override void Read(BinaryReader reader, ulong baselength = 0)
{
InputOffset = (ulong)reader.BaseStream.Position - (ulong)MatroskaExtensions.IdSize(Id);
ulong length;
if (baselength == 0)
reader.Ebml_Read_Length(out length);
else
length = baselength;
Length = length;
InputValueOffset = (ulong)reader.BaseStream.Position;
_inputReader = reader;
reader.BaseStream.Seek((long)length, SeekOrigin.Current);
}