使用directshow播放文件并监听事件的简单例子

编者:李国帅

qq:9611153 微信lgs9611153

时间:2010/8/24

背景原因:

使用directShow进行文件播放,并监听事件。入门例子

播放

Some events are handled silently by the Filter Graph Manager, without the application being notified. Other events are placed on a queue for the application.

#include "stdafx.h"

#include <DShow.h>

 

#pragma comment(lib,"Strmiids.lib")

#pragma comment(lib,"Quartz.lib")

//Strmiids.lib Exports class identifiers (CLSIDs) and interface identifiers (IIDs). All DirectShow applications require this library.

//Quartz.lib Exports the AMGetErrorText function. If you do not call this function, this library is not required.

 

 

int _tmain(int argc, _TCHAR* argv[])

{

    // Initialize the COM library.

    HRESULT hr =CoInitialize(NULL);

    if (FAILED(hr))

    {

        printf("ERROR - Could not initialize COM library");

        perror("CoInitialize failed!");

        exit(-1);

    }

    // Create the filter graph manager and query for interfaces.

    IGraphBuilder *pGraph =NULL;

    hr = CoCreateInstance(CLSID_FilterGraph,NULL,CLSCTX_INPROC_SERVER,IID_IGraphBuilder,(void **)&pGraph);

    if (FAILED(hr))

    {

        printf("ERROR - Could not create the Filter Graph Manager.");

        perror("IGraphBuilder get failed!");

        CoUninitialize();

        exit(-1);

    }

    IMediaControl *pControl =NULL;

    IMediaEvent *pEvent =NULL;

    hr = pGraph->QueryInterface(IID_IMediaControl,(void**)&pControl);

    hr = pGraph->QueryInterface(IID_IMediaEvent,(void**)&pEvent);

 

    // Build the graph. IMPORTANT: Change this string to a file on your system.

    hr = pGraph->RenderFile(L"F:\\Samples\\Media\\chicken_divx.avi",NULL);

    if (SUCCEEDED(hr))

    {

        // Run the graph.

        hr = pControl->Run();

        if (SUCCEEDED(hr))

        {

            // Wait for completion.

            long evCode;

            pEvent->WaitForCompletion(INFINITE, &evCode);

 

            // Note: Do not use INFINITE in a real application, because it can block indefinitely.

        }

    }

    if (FAILED(hr))

    {

        perror("RenderFile failed!");

        pGraph->Release();

        CoUninitialize();

        exit(-1);

    }

 

    pControl->Release();

    pEvent->Release();

    pGraph->Release();

    CoUninitialize();

 

    return 0;

}

 

 

使用窗口句柄接收事件

 

#define WM_GRAPHNOTIFY  WM_APP + 1

IMediaEventEx *g_pEvent = NULL;

 

pGraph->QueryInterface(IID_IMediaEventEx, (void **)&g_pEvent);

g_pEvent->SetNotifyWindow((OAHWND)g_hwnd, WM_GRAPHNOTIFY, 0);

 

//In your application's WindowProc function, add a case statement for the WM_GRAPHNOTIFY message:

case WM_GRAPHNOTIFY:    HandleGraphEvent(); break;

void HandleGraphEvent()

{

    // Disregard if we don't have an IMediaEventEx pointer.

    if (g_pEvent == NULL) return;

 

    // Get all the events

    long evCode, param1, param2;

    HRESULT hr;

    while (SUCCEEDED(g_pEvent->GetEvent(&evCode, &param1, &param2, 0)))

    {

        g_pEvent->FreeEventParams(evCode, param1, param2);

        switch (evCode)

        {

        case EC_COMPLETE:  // Fall through.

        case EC_USERABORT: // Fall through.

        case EC_ERRORABORT:

            CleanUp();

            PostQuitMessage(0);

            return;

        }

    }

}

 

// Disable event notification before releasing the graph.

g_pEvent->SetNotifyWindow(NULL, 0, 0);

g_pEvent->Release();

g_pEvent = NULL;

 

 

 

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转载自blog.csdn.net/lgs790709/article/details/84821377
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