Start the passive decoding.
LONG NET_DVR_MatrixStartPassiveDecode( LONG lUserID, DWORD dwDecChanNum, NET_DVR_MATRIX_PASSIVEMODE *lpPassiveMode );
[IN] Value returned by NET_DVR_Login_V40
[IN] Decoding channel No.
[IN] Passive decoding parameters, see details in the structure NET_DVR_MATRIX_PASSIVEMODE.
Return -1 for failure, and return other values as the parameters of API NET_DVR_MatrixSendData.
If -1 is returned, you can call NET_DVR_GetLastError to get the error code.