IWMEncAudienceObj::get_AudioPeakBitrate

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The get_AudioPeakBitrate method retrieves the peak audio bit rate in the current audience when using peak VBR mode.

Syntax

HRESULT get_AudioPeakBitrate(
  short  iRenderSiteIndex,
  long*  plBitrate
);

Parameters

iRenderSiteIndex

[in]  short containing the audience stream index. Because an audience can only contain one stream of each type, iRenderSiteIndex must be zero.

plBitrate

[out]  Pointer to a long that indicates the peak audio bit rate, in bits per second (bps).

Return Values

If the method succeeds, it returns S_OK. If it fails, it supports the IErrorInfo interface and returns an HRESULT error code.

Return code Number Description
E_POINTER 0x80004003 The pointer to the bit rate is NULL.

Remarks

This method is only relevant when the profile is using peak VBR mode for audio. You can determine which mode is used with the IWMEncProfile2::get_VBRMode method.

Example Code

// Include libraries.
#include <windows.h>
#include <atlbase.h>
#include <comdef.h>
#include "C:\WMSDK\WMEncSDK9\include\wmencode.h"

    // Declare variables.
    HRESULT hr;
    IWMEncoder* pEncoder;
    IWMEncProfileCollection* pProColl;
    IWMEncProfile* pPro;

    IWMEncProfile2* pPro2;
    IWMEncAudienceObj* pAudnc;

    // Initialize the COM library and retrieve a pointer to an IWMEncoder interface.
    hr = CoInitialize(NULL);
    if ( SUCCEEDED( hr ) )
    {
        hr = CoCreateInstance(CLSID_WMEncoder,
            NULL,
            CLSCTX_INPROC_SERVER,
            IID_IWMEncoder,
            (void**) &pEncoder);
    }

    // Retrieve a specific profile.
    if ( SUCCEEDED( hr ) )
    {
        hr = pEncoder->get_ProfileCollection(&pProColl);
    }
    if ( SUCCEEDED( hr ) )
    {
        hr = pProColl->Item(11, &pPro);
    }

    if ( SUCCEEDED( hr ) )
    {
        hr = CoCreateInstance(CLSID_WMEncProfile2,
            NULL,
            CLSCTX_INPROC_SERVER,
            IID_IWMEncProfile2,
            (void**) &pPro2);
    }

    if ( SUCCEEDED( hr ) )
    {
        hr = pPro2->LoadFromIWMProfile(pPro);
    }

    // Retrieve the first audience in the profile.
    if ( SUCCEEDED( hr ) )
    {
        hr = pPro2->get_Audience(0, &pAudnc);
    }

    // Retrieve the value for the peak bit rate for audio.
    long lAudPeakBRate;
    if ( SUCCEEDED( hr ) )
    {
        hr = pAudnc->get_AudioPeakBitrate(0, &lAudPeakBRate); 
    }

    // Release pointers.
    if ( pAudnc )
    {
        pAudnc->Release();
        pAudnc = NULL;
    }
    if ( pPro2 )
    {
        pPro2->Release();
        pPro2 = NULL;
    }

Requirements

Header: wmencode.h

Library: wmenc.exe

See Also