/// <summary>Marshals a FLAC LPC subframe</summary>
/// <param name="frameHandle">Handle to unmanaged memory containing the frame</param>
/// <param name="offset">Offset at which to begin reading this subframe</param>
/// <returns>The marshaled LPC subframe</returns>
private static LpcSubframe marshalLpcSubframe(IntPtr frameHandle, int offset)
{
LpcSubframe lpcSubframe = new LpcSubframe();
lpcSubframe.EntropyCodingMethod = marshalEntropyCodingMethod(frameHandle, offset);
lpcSubframe.Order = Marshal.ReadInt32(frameHandle, offset + 12);
lpcSubframe.QlpCoefficientPrecision = Marshal.ReadInt32(frameHandle, offset + 16);
lpcSubframe.QuantizationLevel = Marshal.ReadInt32(frameHandle, offset + 20);
offset += 24;
// Marshal the array of QLP Coefficients
lpcSubframe.QlpCoefficients = new int[Constants.MaximumLpcOrder];
for (
int index = 0; index < Constants.MaximumLpcOrder; ++index
)
{
lpcSubframe.QlpCoefficients[index] = Marshal.ReadInt32(
frameHandle, offset + index * 4
);
}
offset += Constants.MaximumLpcOrder * 4;
// Marshal the Warmup values for the LPC decoder
lpcSubframe.Warmup = new int[Constants.MaximumLpcOrder];
for (
int index = 0; index < Constants.MaximumLpcOrder; ++index
)
{
lpcSubframe.Warmup[index] = Marshal.ReadInt32(
frameHandle, offset + index * 4
);
}
offset += Constants.MaximumLpcOrder * 4;
lpcSubframe.Residual = null;
return(lpcSubframe);
}
/// <summary>Marshals a FLAC LPC subframe</summary>
/// <param name="frameHandle">Handle to unmanaged memory containing the frame</param>
/// <param name="offset">Offset at which to begin reading this subframe</param>
/// <returns>The marshaled LPC subframe</returns>
private static LpcSubframe marshalLpcSubframe(IntPtr frameHandle, int offset) {
LpcSubframe lpcSubframe = new LpcSubframe();
lpcSubframe.EntropyCodingMethod = marshalEntropyCodingMethod(frameHandle, offset);
lpcSubframe.Order = Marshal.ReadInt32(frameHandle, offset + 12);
lpcSubframe.QlpCoefficientPrecision = Marshal.ReadInt32(frameHandle, offset + 16);
lpcSubframe.QuantizationLevel = Marshal.ReadInt32(frameHandle, offset + 20);
offset += 24;
// Marshal the array of QLP Coefficients
lpcSubframe.QlpCoefficients = new int[Constants.MaximumLpcOrder];
for(
int index = 0; index < Constants.MaximumLpcOrder; ++index
) {
lpcSubframe.QlpCoefficients[index] = Marshal.ReadInt32(
frameHandle, offset + index * 4
);
}
offset += Constants.MaximumLpcOrder * 4;
// Marshal the Warmup values for the LPC decoder
lpcSubframe.Warmup = new int[Constants.MaximumLpcOrder];
for(
int index = 0; index < Constants.MaximumLpcOrder; ++index
) {
lpcSubframe.Warmup[index] = Marshal.ReadInt32(
frameHandle, offset + index * 4
);
}
offset += Constants.MaximumLpcOrder * 4;
lpcSubframe.Residual = null;
return lpcSubframe;
}