IWMSActiveStream::get_BitRate

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IWMSActiveStream::get_BitRate

The get_BitRate method retrieves the maximum bit rate of a stream.

Syntax

  HRESULT get_BitRate(
  long*  pVal
);

Parameters

pVal

[out] Pointer to a long containing the maximum bit rate in Kbps.

Return Values

If the method succeeds, it returns S_OK. If it fails, it returns an HRESULT error code.

Return code Number Description
E_POINTER 0x80004003 pVal is a NULL pointer argument.

Remarks

Optimizing codecs encode streams at variable bit rates. Complex items in the stream require a higher bit rate to be properly rendered by the client.

Example Code

#include <windows.h>
#include <atlbase.h>    // Includes CComVariant.
#include "wmsserver.h"

// Declare variables and interfaces.
HRESULT             hr;
IWMSServer          *pServer;
IWMSPlayers         *pPlayers;
IWMSPlayer          *pPlayer;
IWMSPlaylist        *pPlaylist;
IWMSActiveMedia     *pActiveMedia;
IWMSActiveStreams   *pActiveStreams;
IWMSActiveStream    *pActiveStream;

CComVariant         varIndex;
long                lCount;
long                lBitRate;

// Initialize the COM library and retrieve a pointer
// to the IWMSServer interface.
hr = CoInitialize(NULL);
hr = CoCreateInstance(CLSID_WMSServer,
                      NULL,
                      CLSCTX_ALL,
                      IID_IWMSServer,
                      (void **)&pServer);
if (FAILED(hr)) goto EXIT;

// Retrieve a pointer to the IWMSPlayers interface
// and retrieve the number of connected players.
hr = pServer->get_Players(&pPlayers);
if (FAILED(hr)) goto EXIT;
hr = pPlayers->get_Count(&lCount);
if (FAILED(hr)) goto EXIT;

// If players are connected, retrieve a pointer to
// an IWMSPlayer interface containing the first player.
if (lCount > 0)
{
    varIndex = 0;
    hr = pPlayers->get_Item(varIndex, &pPlayer);
    if (FAILED(hr)) goto EXIT;
}

// Retrieve the playlist for the player.
// NOTE: A valid playlist file is not always returned. This may be
// the case, for example, if the user requested a specific content
// file or if a broadcast publishing point is being used.
hr = pPlayer->get_RequestedPlaylist(&pPlaylist);
if (FAILED(hr)) goto EXIT;
if (pPlaylist != NULL)
{
    // Retrieve a pointer to the IWMSActiveMedia interface.
    hr = pPlaylist->get_CurrentMediaInformation(&pActiveMedia);
    if (FAILED(hr)) goto EXIT;

    // Retrieve a pointer to the IWMSActiveStreams interface
    // and retrieve the total number of active streams.
    hr = pActiveMedia->get_Streams(&pActiveStreams);
    if (FAILED(hr)) goto EXIT;
    hr = pActiveStreams->get_Count(&lCount);
    if (FAILED(hr)) goto EXIT;

    // Retrieve information about each active stream.
    for (int x = 0; x < lCount; x++) {

        // Retrieve a pointer to the IWMSActiveStream interface.
        varIndex = x;
        hr = pActiveStreams->get_Item(varIndex, &pActiveStream);
        if (FAILED(hr)) goto EXIT;

        // Retrieve the bit rate.
        hr = pActiveStream->get_BitRate(&lBitRate);
        if (FAILED(hr)) goto EXIT;

        // Release temporary COM objects.
        pActiveStream->Release();
    }
}

EXIT:
    // TODO: Release temporary COM objects and uninitialize COM.

Requirements

Header: wmsserver.h.

Library: WMSServerTypeLib.dll.

Platform: Windows ServerĀ 2003 family, Windows ServerĀ 2008 family.

See Also

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