'Declaration
Public Function TwainGetBitDepth() As Integer
public int TwainGetBitDepth()
public function TwainGetBitDepth(): Integer;
public function TwainGetBitDepth() : int;
public: int TwainGetBitDepth();
public: int TwainGetBitDepth();
Return Value
If success: bit depth value. Else 0 if fail -> Use TwainGetLastResultCode() and
TwainGetLastConditionCode() methods for diagnosing the error.