DirectShow学习之二做一个简单的媒体文件播放器
DirectShow学习之二做一个简单的媒体文件播放器
分类： J:DirectShow学习
2008-03-16 11:10
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作者：liguisen
Blog： http://blog.csdn.net/liguisen
或许你现在还不知道directshow是什么东西，不过你应该知道它可以用来播放电影，ok，我们就做一个简单的媒体文件播放器。什么？我还不知道ds的原理呢，我不懂com呢，我甚至没有什么windows程序的经验呢。都没关系，我们先有一点成就感，再逐步深入。愣是够！
首先，我们需要找两个叫做CDXGraph.h和CDXGraph.cpp的文件。在DX90SDK安装目录搜索了一遍，没有，在网上搜索一把，嗯，有很多，原来是一个“使用directShow播放mpeg的基类”，是“自定义的Filter Graph Manager的一个封装类”，（不知道Filter Graph Manager？没关系），作者不详，本文后面将列出。
第一步：（本文使用vs2005）建立一个名叫MyPlayer的MFC dialog based工程。
第二步：配置链接库，假设当前工程是debug版本（这都不清楚的话，嗯，还是慢慢来，先掌握基础好了），则打开project->properties->configuration properties->Linker ->Input->Additional Dependencies增加strmbasd.lib uuid.lib winmm.lib（以后不会说这么详细了）。
自己的话：项目---xxxx属性----配置属性---链接器-----输入-----附加依赖项 增加strmbasd.lib uuid.lib winmm.lib三项，需要手工输入，分行
第三步：COM库的初始化和清除，直接列出代码了（把系统的注释去掉了）
BOOL CMyPlayerApp::InitInstance()
{
INITCOMMONCONTROLSEX InitCtrls;
InitCtrls.dwSize = sizeof(InitCtrls);
InitCtrls.dwICC = ICC_WIN95_CLASSES;
InitCommonControlsEx(&InitCtrls);
CWinApp::InitInstance();
AfxEnableControlContainer();
SetRegistryKey(_T("Local AppWizard-Generated Applications"));
CoInitialize(NULL);//这是我们要增加的，com库的初始化
CMyPlayerDlg dlg;
m_pMainWnd = &dlg;
INT_PTR nResponse = dlg.DoModal();
if (nResponse == IDOK)
{
}
else if (nResponse == IDCANCEL)
{
}
return FALSE;
}
//友情提示，下面这个函数系统并没有自动添加，在CMyPlayerApp类
//的properties里单击overrides可找到，发现很多用惯了vc6的“老程序员”
//没有了向导很不习惯呢。
int CMyPlayerApp::ExitInstance()
{
CoUninitialize();//这是我们要增加的，清除com库
return CWinApp::ExitInstance();
}
第四步：界面开发。
在对话框上放置一个Picture Control，（此类静态控件默认ID为IDC_STATIC,如果在程序中不对它们进行控制,不用修改ID,如果要控制,必须修改其ID号,才可对它进行代码控制,包括添加变量），修改ID为IDC_VIDEO_WINDOW，关联一个Control变量mVideoWindow。
添加一个“打开”和“播放”按钮。
第五步：添加CDXGraph.h和CDXGraph.cpp到工程。首先把这两个文件复制到工程源代码所在的地方，然后打开Project->Add Existing Item把它们真正加到工程。
第六步： MyPlayerDlg.h 增加include，如下：
#include "afxwin.h"
#include <streams.h>
#include "CDXGraph.h"
再增加两个成员变量：
CDXGraph *
mFilterGraph; // Filter Graph封装
CString
mSourceFile; // 源文件
并做一些初始化工作：
CMyPlayerDlg::CMyPlayerDlg(CWnd* pParent /*=NULL*/)
: CDialog(CMyPlayerDlg::IDD, pParent)
{
m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME);
mFilterGraph = NULL;
mSourceFile = "";
}
此时F7编译，如果出现问题，请参考第一篇
DirectShow学习之一在vs2005中配置directshow开发环境 。
第七步：添加成员函数CreateGraph和DestroyGraph，编写代码如下：
void CMyPlayerDlg::CreateGraph(void)
{
DestroyGraph();
mFilterGraph = new CDXGraph();
if (mFilterGraph->Create())
{
mFilterGraph->RenderFile(mSourceFile);
mFilterGraph->SetDisplayWindow(mVideoWindow.GetSafeHwnd());
mFilterGraph->SetNotifyWindow(this->GetSafeHwnd());
mFilterGraph->Pause();
}
}
void CMyPlayerDlg::DestroyGraph(void)
{
if (mFilterGraph)
{
mFilterGraph->Stop();
mFilterGraph->SetNotifyWindow(NULL);
delete mFilterGraph;
mFilterGraph = NULL;
}
}
第八步：实现“打开”功能。
添加一个实现函数：
void CMyPlayerDlg::OnBnClickedButtonOpen()
{
// TODO: Add your control notification handler code here
CString strFilter = "MPEG File (*.mpg;*.mpeg)|*.mpg;*.mpeg|";
strFilter += "AVI File (*.avi)|*.avi|";
strFilter += "Mp3 File (*.mp3)|*.mp3|";
strFilter += "Wave File (*.wav)|*.wav|";
strFilter += "All Files (*.*)|*.*|";
CFileDialog dlgOpen(TRUE, NULL, NULL, OFN_PATHMUSTEXIST | OFN_HIDEREADONLY,
strFilter, this);
if (IDOK == dlgOpen.DoModal())
{
mSourceFile = dlgOpen.GetPathName();
CreateGraph();
}
}
此时，编译运行程序，打开一个mpeg文件，应该能显示第一帧的画面了。
第九步：实现“播放”功能。
添加一个实现函数：
void CMyPlayerDlg::OnBnClickedButtonPlay()
{
// TODO: Add your control notification handler code here
if (mFilterGraph)
{
mFilterGraph->Run();
}
}
基本上，我们现在就可以用它来看电影了，呵呵。不过，还是有点小问题，当画面被其它窗口挡住之后，再重新出来，画面没了，不能更新，这是小问题：在OnInitDialog()里的return TRUE;前加一句mVideoWindow.ModifyStyle(0, WS_CLIPCHILDREN);然后添加主对话框的WM_ERASEBKGND消息响应：
BOOL CMyPlayerDlg::OnEraseBkgnd(CDC* pDC)
{
// TODO: Add your message handler code here and/or call default
CRect rc;
mVideoWindow.GetWindowRect(&rc);
ScreenToClient(&rc);
pDC->ExcludeClipRect(&rc);
return CDialog::OnEraseBkgnd(pDC);
}
尽管太过于简陋，但是，毕竟是一个播放器了，下一篇将详细分析程序的实现过程，重点是CDXGraph类。
附：CDXGraph.h和CDXGraph.cpp
//
// CDXGraph.h
//
#ifndef __H_CDXGraph__
#define __H_CDXGraph__
// Filter graph notification to the specified window
#define WM_GRAPHNOTIFY (WM_USER+20)
class CDXGraph
{
private:
IGraphBuilder * mGraph;
IMediaControl * mMediaControl;
IMediaEventEx * mEvent;
IBasicVideo * mBasicVideo;
IBasicAudio * mBasicAudio;
IVideoWindow * mVideoWindow;
IMediaSeeking * mSeeking;
DWORD mObjectTableEntry;
public:
CDXGraph();
virtual ~CDXGraph();
public:
virtual bool Create(void);
virtual void Release(void);
virtual bool Attach(IGraphBuilder * inGraphBuilder);
IGraphBuilder * GetGraph(void); // Not outstanding reference count
IMediaEventEx * GetEventHandle(void);
bool ConnectFilters(IPin * inOutputPin, IPin * inInputPin, const AM_MEDIA_TYPE * inMediaType = 0);
void DisconnectFilters(IPin * inOutputPin);
bool SetDisplayWindow(HWND inWindow);
bool SetNotifyWindow(HWND inWindow);
bool ResizeVideoWindow(long inLeft, long inTop, long inWidth, long inHeight);
void HandleEvent(WPARAM inWParam, LPARAM inLParam);
bool Run(void); // Control filter graph
bool Stop(void);
bool Pause(void);
bool IsRunning(void); // Filter graph status
bool IsStopped(void);
bool IsPaused(void);
bool SetFullScreen(BOOL inEnabled);
bool GetFullScreen(void);
// IMediaSeeking
bool GetCurrentPosition(double * outPosition);
bool GetStopPosition(double * outPosition);
bool SetCurrentPosition(double inPosition);
bool SetStartStopPosition(double inStart, double inStop);
bool GetDuration(double * outDuration);
bool SetPlaybackRate(double inRate);
// Attention: range from -10000 to 0, and 0 is FULL_VOLUME.
bool SetAudioVolume(long inVolume);
long GetAudioVolume(void);
// Attention: range from -10000(left) to 10000(right), and 0 is both.
bool SetAudioBalance(long inBalance);
long GetAudioBalance(void);
bool RenderFile(const char * inFile);
bool SnapshotBitmap(const char * outFile);
private:
void AddToObjectTable(void) ;
void RemoveFromObjectTable(void);
bool QueryInterfaces(void);
};
#endif // __H_CDXGraph__
//
// CDXGraph.cpp
//
#include "stdafx.h"
#include <streams.h>
#include "CDXGraph.h"
#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif
////////////////////////////////////////////////////////////////////////////////
CDXGraph::CDXGraph()
{
mGraph = NULL;
mMediaControl = NULL;
mEvent = NULL;
mBasicVideo = NULL;
mBasicAudio = NULL;
mVideoWindow = NULL;
mSeeking = NULL;
mObjectTableEntry = 0;
}
CDXGraph::~CDXGraph()
{
Release();
}
bool CDXGraph::Create(void)
{
if (!mGraph)
{
if (SUCCEEDED(CoCreateInstance(CLSID_FilterGraph, NULL, CLSCTX_INPROC_SERVER,
IID_IGraphBuilder, (void **)&mGraph)))
{
AddToObjectTable();
return QueryInterfaces();
}
mGraph = 0;
}
return false;
}
bool CDXGraph::QueryInterfaces(void)
{
if (mGraph)
{
HRESULT hr = NOERROR;
hr |= mGraph->QueryInterface(IID_IMediaControl, (void **)&mMediaControl);
hr |= mGraph->QueryInterface(IID_IMediaEventEx, (void **)&mEvent);
hr |= mGraph->QueryInterface(IID_IBasicVideo, (void **)&mBasicVideo);
hr |= mGraph->QueryInterface(IID_IBasicAudio, (void **)&mBasicAudio);
hr |= mGraph->QueryInterface(IID_IVideoWindow, (void **)&mVideoWindow);
hr |= mGraph->QueryInterface(IID_IMediaSeeking, (void **)&mSeeking);
if (mSeeking)
{
mSeeking->SetTimeFormat(&TIME_FORMAT_MEDIA_TIME);
}
return SUCCEEDED(hr);
}
return false;
}
void CDXGraph::Release(void)
{
if (mSeeking)
{
mSeeking->Release();
mSeeking = NULL;
}
if (mMediaControl)
{
mMediaControl->Release();
mMediaControl = NULL;
}
if (mEvent)
{
mEvent->Release();
mEvent = NULL;
}
if (mBasicVideo)
{
mBasicVideo->Release();
mBasicVideo = NULL;
}
if (mBasicAudio)
{
mBasicAudio->Release();
mBasicAudio = NULL;
}
if (mVideoWindow)
{
mVideoWindow->put_Visible(OAFALSE);
mVideoWindow->put_MessageDrain((OAHWND)NULL);
mVideoWindow->put_Owner(OAHWND(0));
mVideoWindow->Release();
mVideoWindow = NULL;
}
RemoveFromObjectTable();
if (mGraph)
{
mGraph->Release();
mGraph = NULL;
}
}
bool CDXGraph::Attach(IGraphBuilder * inGraphBuilder)
{
Release();
if (inGraphBuilder)
{
inGraphBuilder->AddRef();
mGraph = inGraphBuilder;
AddToObjectTable();
return QueryInterfaces();
}
return true;
}
IGraphBuilder * CDXGraph::GetGraph(void)
{
return mGraph;
}
IMediaEventEx * CDXGraph::GetEventHandle(void)
{
return mEvent;
}
// Connect filter from the upstream output pin to the downstream input pin
bool CDXGraph::ConnectFilters(IPin * inOutputPin, IPin * inInputPin,
const AM_MEDIA_TYPE * inMediaType)
{
if (mGraph && inOutputPin && inInputPin)
{
HRESULT hr = mGraph->ConnectDirect(inOutputPin, inInputPin, inMediaType);
return SUCCEEDED(hr) ? true : false;
}
return false;
}
void CDXGraph::DisconnectFilters(IPin * inOutputPin)
{
if (mGraph && inOutputPin)
{
HRESULT hr = mGraph->Disconnect(inOutputPin);
}
}
bool CDXGraph::SetDisplayWindow(HWND inWindow)
{
if (mVideoWindow)
{
// long lVisible;
// mVideoWindow->get_Visible(&lVisible);
// Hide the video window first
mVideoWindow->put_Visible(OAFALSE);
mVideoWindow->put_Owner((OAHWND)inWindow);
RECT windowRect;
::GetClientRect(inWindow, &windowRect);
mVideoWindow->put_Left(0);
mVideoWindow->put_Top(0);
mVideoWindow->put_Width(windowRect.right - windowRect.left);
mVideoWindow->put_Height(windowRect.bottom - windowRect.top);
mVideoWindow->put_WindowStyle(WS_CHILD|WS_CLIPCHILDREN|WS_CLIPSIBLINGS);
mVideoWindow->put_MessageDrain((OAHWND) inWindow);
// Restore the video window
if (inWindow != NULL)
{
// mVideoWindow->put_Visible(lVisible);
mVideoWindow->put_Visible(OATRUE);
}
else
{
mVideoWindow->put_Visible(OAFALSE);
}
return true;
}
return false;
}
bool CDXGraph::ResizeVideoWindow(long inLeft, long inTop, long inWidth, long inHeight)
{
if (mVideoWindow)
{
long lVisible = OATRUE;
mVideoWindow->get_Visible(&lVisible);
// Hide the video window first
mVideoWindow->put_Visible(OAFALSE);
mVideoWindow->put_Left(inLeft);
mVideoWindow->put_Top(inTop);
mVideoWindow->put_Width(inWidth);
mVideoWindow->put_Height(inHeight);
// Restore the video window
mVideoWindow->put_Visible(lVisible);
return true;
}
return false;
}
bool CDXGraph::SetNotifyWindow(HWND inWindow)
{
if (mEvent)
{
mEvent->SetNotifyWindow((OAHWND)inWindow, WM_GRAPHNOTIFY, 0);
return true;
}
return false;
}
void CDXGraph::HandleEvent(WPARAM inWParam, LPARAM inLParam)
{
if (mEvent)
{
LONG eventCode = 0, eventParam1 = 0, eventParam2 = 0;
while (SUCCEEDED(mEvent->GetEvent(&eventCode, &eventParam1, &eventParam2, 0)))
{
mEvent->FreeEventParams(eventCode, eventParam1, eventParam2);
switch (eventCode)
{
case EC_COMPLETE:
break;
case EC_USERABORT:
case EC_ERRORABORT:
break;
default:
break;
}
}
}
}
bool CDXGraph::Run(void)
{
if (mGraph && mMediaControl)
{
if (!IsRunning())
{
if (SUCCEEDED(mMediaControl->Run()))
{
return true;
}
}
else
{
return true;
}
}
return false;
}
bool CDXGraph::Stop(void)
{
if (mGraph && mMediaControl)
{
if (!IsStopped())
{
if (SUCCEEDED(mMediaControl->Stop()))
{
return true;
}
}
else
{
return true;
}
}
return false;
}
bool CDXGraph::Pause(void)
{
if (mGraph && mMediaControl)
{
if (!IsPaused())
{
if (SUCCEEDED(mMediaControl->Pause()))
{
return true;
}
}
else
{
return true;
}
}
return false;
}
bool CDXGraph::IsRunning(void)
{
if (mGraph && mMediaControl)
{
OAFilterState state = State_Stopped;
if (SUCCEEDED(mMediaControl->GetState(10, &state)))
{
return state == State_Running;
}
}
return false;
}
bool CDXGraph::IsStopped(void)
{
if (mGraph && mMediaControl)
{
OAFilterState state = State_Stopped;
if (SUCCEEDED(mMediaControl->GetState(10, &state)))
{
return state == State_Stopped;
}
}
return false;
}
bool CDXGraph::IsPaused(void)
{
if (mGraph && mMediaControl)
{
OAFilterState state = State_Stopped;
if (SUCCEEDED(mMediaControl->GetState(10, &state)))
{
return state == State_Paused;
}
}
return false;
}
bool CDXGraph::SetFullScreen(BOOL inEnabled)
{
if (mVideoWindow)
{
HRESULT hr = mVideoWindow->put_FullScreenMode(inEnabled ? OATRUE : OAFALSE);
return SUCCEEDED(hr);
}
return false;
}
bool CDXGraph::GetFullScreen(void)
{
if (mVideoWindow)
{
long fullScreenMode = OAFALSE;
mVideoWindow->get_FullScreenMode(&fullScreenMode);
return (fullScreenMode == OATRUE);
}
return false;
}
// IMediaSeeking features
bool CDXGraph::GetCurrentPosition(double * outPosition)
{
if (mSeeking)
{
__int64 position = 0;
if (SUCCEEDED(mSeeking->GetCurrentPosition(&position)))
{
*outPosition = ((double)position) / 10000000.;
return true;
}
}
return false;
}
bool CDXGraph::GetStopPosition(double * outPosition)
{
if (mSeeking)
{
__int64 position = 0;
if (SUCCEEDED(mSeeking->GetStopPosition(&position)))
{
*outPosition = ((double)position) / 10000000.;
return true;
}
}
return false;
}
bool CDXGraph::SetCurrentPosition(double inPosition)
{
if (mSeeking)
{
__int64 one = 10000000;
__int64 position = (__int64)(one * inPosition);
HRESULT hr = mSeeking->SetPositions(&position, AM_SEEKING_AbsolutePositioning | AM_SEEKING_SeekToKeyFrame,
0, AM_SEEKING_NoPositioning);
return SUCCEEDED(hr);
}
return false;
}
bool CDXGraph::SetStartStopPosition(double inStart, double inStop)
{
if (mSeeking)
{
__int64 one = 10000000;
__int64 startPos = (__int64)(one * inStart);
__int64 stopPos = (__int64)(one * inStop);
HRESULT hr = mSeeking->SetPositions(&startPos, AM_SEEKING_AbsolutePositioning | AM_SEEKING_SeekToKeyFrame,
&stopPos, AM_SEEKING_AbsolutePositioning | AM_SEEKING_SeekToKeyFrame);
return SUCCEEDED(hr);
}
return false;
}
bool CDXGraph::GetDuration(double * outDuration)
{
if (mSeeking)
{
__int64 length = 0;
if (SUCCEEDED(mSeeking->GetDuration(&length)))
{
*outDuration = ((double)length) / 10000000.;
return true;
}
}
return false;
}
bool CDXGraph::SetPlaybackRate(double inRate)
{
if (mSeeking)
{
if (SUCCEEDED(mSeeking->SetRate(inRate)))
{
return true;
}
}
return false;
}
// Attention: range from -10000 to 0, and 0 is FULL_VOLUME.
bool CDXGraph::SetAudioVolume(long inVolume)
{
if (mBasicAudio)
{
HRESULT hr = mBasicAudio->put_Volume(inVolume);
return SUCCEEDED(hr);
}
return false;
}
long CDXGraph::GetAudioVolume(void)
{
long volume = 0;
if (mBasicAudio)
{
mBasicAudio->get_Volume(&volume);
}
return volume;
}
// Attention: range from -10000(left) to 10000(right), and 0 is both.
bool CDXGraph::SetAudioBalance(long inBalance)
{
if (mBasicAudio)
{
HRESULT hr = mBasicAudio->put_Balance(inBalance);
return SUCCEEDED(hr);
}
return false;
}
long CDXGraph::GetAudioBalance(void)
{
long balance = 0;
if (mBasicAudio)
{
mBasicAudio->get_Balance(&balance);
}
return balance;
}
bool CDXGraph::RenderFile(const char * inFile)
{
if (mGraph)
{
WCHAR szFilePath[MAX_PATH];
MultiByteToWideChar(CP_ACP, 0, inFile, -1, szFilePath, MAX_PATH);
if (SUCCEEDED(mGraph->RenderFile(szFilePath, NULL)))
{
return true;
}
}
return false;
}
bool CDXGraph::SnapshotBitmap(const char * outFile)
{
if (mBasicVideo)
{
long bitmapSize = 0;
if (SUCCEEDED(mBasicVideo->GetCurrentImage(&bitmapSize, 0)))
{
bool pass = false;
unsigned char * buffer = new unsigned char[bitmapSize];
if (SUCCEEDED(mBasicVideo->GetCurrentImage(&bitmapSize, (long *)buffer)))
{
BITMAPFILEHEADER hdr;
LPBITMAPINFOHEADER lpbi;
lpbi = (LPBITMAPINFOHEADER)buffer;
int nColors = 1 << lpbi->biBitCount;
if (nColors > 256)
nColors = 0;
hdr.bfType = ((WORD) ('M' << 8) | 'B'); //always is "BM"
hdr.bfSize = bitmapSize + sizeof( hdr );
hdr.bfReserved1 = 0;
hdr.bfReserved2 = 0;
hdr.bfOffBits = (DWORD) (sizeof(BITMAPFILEHEADER) + lpbi->biSize +
nColors * sizeof(RGBQUAD));
CFile bitmapFile(outFile, CFile::modeReadWrite | CFile::modeCreate | CFile::typeBinary);
bitmapFile.Write(&hdr, sizeof(BITMAPFILEHEADER));
bitmapFile.Write(buffer, bitmapSize);
bitmapFile.Close();
pass = true;
}
delete [] buffer;
return pass;
}
}
return false;
}
//////////////////////// For GraphEdit Dubug purpose /////////////////////////////
void CDXGraph::AddToObjectTable(void)
{
IMoniker * pMoniker = 0;
IRunningObjectTable * objectTable = 0;
if (SUCCEEDED(GetRunningObjectTable(0, &objectTable)))
{
WCHAR wsz[256];
wsprintfW(wsz, L"FilterGraph %08p pid %08x", (DWORD_PTR)mGraph, GetCurrentProcessId());
HRESULT hr = CreateItemMoniker(L"!", wsz, &pMoniker);
if (SUCCEEDED(hr))
{
hr = objectTable->Register(0, mGraph, pMoniker, &mObjectTableEntry);
pMoniker->Release();
}
objectTable->Release();
}
}
void CDXGraph::RemoveFromObjectTable(void)
{
IRunningObjectTable * objectTable = 0;
if (SUCCEEDED(GetRunningObjectTable(0, &objectTable)))
{
objectTable->Revoke(mObjectTableEntry);
objectTable->Release();
mObjectTableEntry = 0;
}
}