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adiModifyEchoCanceller
Description
- Modifes the echo cancellation setting. Available with CT Access 4.0 or higher.
Prototype
- DWORD adiModifyEchoCanceller ( CTAHD ctahd,
ADI_ECHOCANCEL_PARMS *parms )
- ctahd CTA context handle returned by ctaCreateContext.
- parms Pointer to echo cancellation parameters, as shown:
- typedef struct
- /* parameters for echo cancellation */
- DWORD size; /* size of this structure */
- DWORD mode; /* echo canceller mode */
- DWORD filterlength; /* fiter length (msec) */
- DWORD adapttime; /* filter adaptation time (msec) */
- DWORD predelay; /* offset of input sample (msec) */
- INT32 gain; /* receive gain (db) */
- } ADI_ECHOCANCEL_PARMS ;
Return Values
Events
- None.
DSP File
- This function is supported on AG 2000, AG 4000, AG 4000C, and CG 6000C boards running CT Access 4.0. On AG 2000 and AG 4000 boards, echo.m54 must be loaded before adiModifyEchoCanceller will work. On CG 6000C boards, echo.f54 must be loaded before adiModifyEchoCanceller will work.
- Refer to the board-specific installation and developer's manual for more information about MIPS usage.
Details
- This function modifies the echo cancellation setting. The echo canceller must be started before this function will work. For more information on how to start the echo canceller, see adiStartProtocol.
- The various features of the echo canceller can be enabled or disabled by setting the proper bits in the mode parameter. The gain applied to the near end input and the predelay applied to the far end input can also be changed.
- Current implementation of this API does not allow the filterlength and adapttime parameters to be changed. These parameters are ignored.
- For more information about the adiModifyEchoCanceller parameter fields, refer to ADI.START.ECHOCANCEL in Appendix C.
See Also
- adiStartProtocol
Example
int myDisableEchoAdapt( CTAHD ctahd )
{
ADI_START_PARMS startParms;
ADI_ECHOCANCEL_PARMS *echoParms;
/* get echo canceller parameters used by protocol for this ctahd */
ctaGetParms ( ctahd, ADI_START_PARMID,
&startParms, sizeof(startParms) );
echoParms = &startParms.echocancel;
echoParms->mode |= ADI_ECHOCANCEL_NO_ADAPT;
if( adiModifyEchoCanceller( ctahd, echoParms ) !=SUCCESS )
return MYFAILURE;
/* update the parameters */
ctaSetParmByName( ctahd, "adi.start",
&startParms, sizeof(startParms) );
return MYSUCCESS;
}
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