Media Player Classic - HC 源代码分析 3：核心类 （CMainFrame）（2）

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Media Player Classic - HC 源代码分析系列文章列表：

Media Player Classic - HC 源代码分析 1：整体结构

Media Player Classic - HC 源代码分析 2：核心类 （CMainFrame）（1）

Media Player Classic - HC 源代码分析 3：核心类 （CMainFrame）（2）

Media Player Classic - HC 源代码分析 4：核心类 （CMainFrame）（3）

Media Player Classic - HC 源代码分析 5：关于对话框 （CAboutDlg）

Media Player Classic - HC 源代码分析 6：MediaInfo选项卡 （CPPageFileMediaInfo）

Media Player Classic - HC 源代码分析 7：详细信息选项卡（CPPageFileInfoDetails）

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上一篇文章分析了Media Player Classic - HC（mpc-hc）的源代码中的核心类 CMainFrame：Media Player Classic - HC 源代码分析 2：核心类 （CMainFrame）（1）

主要介绍了CMainFrame类中的以下几个函数（“->”代表调用关系）：

OpenMedia()->OpenMediaPrivate()->OpenFile()

本文补充介绍CMainFrame类中的其他一些函数。

再回顾一下打开文件功能主要所在的函数OpenMediaPrivate()：

//打开一个媒体（private）
bool CMainFrame::OpenMediaPrivate(CAutoPtr<OpenMediaData> pOMD)
{
//获得设置信息
CAppSettings& s = AfxGetAppSettings();

if (m_iMediaLoadState != MLS_CLOSED) {
ASSERT(0);
return false;
}
//OpenFileData
//OpenDVDData
//OpenDeviceData
//里面包含了文件或者DVD信息（名称等）
OpenFileData* pFileData = dynamic_cast<OpenFileData*>(pOMD.m_p);
OpenDVDData* pDVDData = dynamic_cast<OpenDVDData*>(pOMD.m_p);
OpenDeviceData* pDeviceData = dynamic_cast<OpenDeviceData*>(pOMD.m_p);
if (!pFileData && !pDVDData  && !pDeviceData) {
ASSERT(0);
return false;
}

// Clear DXVA state ...
ClearDXVAState();

#ifdef _DEBUG
// Debug trace code - Begin
// Check for bad / buggy auto loading file code
if (pFileData) {
POSITION pos = pFileData->fns.GetHeadPosition();
UINT index = 0;
while (pos != nullptr) {
CString path = pFileData->fns.GetNext(pos);
TRACE(_T("--> CMainFrame::OpenMediaPrivate - pFileData->fns[%d]:\n"), index);
TRACE(_T("\t%ws\n"), path.GetString()); // %ws - wide character string always
index++;
}
}
// Debug trace code - End
#endif

CString mi_fn = _T("");

if (pFileData) {
if (pFileData->fns.IsEmpty()) {
return false;
}

CString fn = pFileData->fns.GetHead();

int i = fn.Find(_T(":\\"));
if (i > 0) {
CString drive = fn.Left(i + 2);
UINT type = GetDriveType(drive);
CAtlList<CString> sl;
if (type == DRIVE_REMOVABLE || type == DRIVE_CDROM && GetCDROMType(drive[0], sl) != CDROM_Audio) {
int ret = IDRETRY;
while (ret == IDRETRY) {
WIN32_FIND_DATA findFileData;
HANDLE h = FindFirstFile(fn, &findFileData);
if (h != INVALID_HANDLE_VALUE) {
FindClose(h);
ret = IDOK;
} else {
CString msg;
msg.Format(IDS_MAINFRM_114, fn);
ret = AfxMessageBox(msg, MB_RETRYCANCEL);
}
}

if (ret != IDOK) {
return false;
}
}
mi_fn = fn;
}
}

SetLoadState(MLS_LOADING);

// FIXME: Don't show "Closed" initially
PostMessage(WM_KICKIDLE);

CString err;

m_fUpdateInfoBar = false;
BeginWaitCursor();

try {
CComPtr<IVMRMixerBitmap9>    pVMB;
CComPtr<IMFVideoMixerBitmap> pMFVMB;
CComPtr<IMadVRTextOsd>       pMVTO;
if (m_fOpeningAborted) {
throw (UINT)IDS_AG_ABORTED;
}

OpenCreateGraphObject(pOMD);

if (m_fOpeningAborted) {
throw (UINT)IDS_AG_ABORTED;
}

SetupIViAudReg();

if (m_fOpeningAborted) {
throw (UINT)IDS_AG_ABORTED;
}
//按类型的不同打开不同的文件
if (pFileData) {
//文件
OpenFile(pFileData);
} else if (pDVDData) {
//DVD
OpenDVD(pDVDData);
} else if (pDeviceData) {
if (s.iDefaultCaptureDevice == 1) {
HRESULT hr = OpenBDAGraph();
if (FAILED(hr)) {
throw (UINT)IDS_CAPTURE_ERROR_DEVICE;
}
} else {
OpenCapture(pDeviceData);
}
} else {
throw (UINT)IDS_INVALID_PARAMS_ERROR;
}

m_pCAP2 = nullptr;
m_pCAP = nullptr;
//查找接口
m_pGB->FindInterface(__uuidof(ISubPicAllocatorPresenter), (void**)&m_pCAP, TRUE);
m_pGB->FindInterface(__uuidof(ISubPicAllocatorPresenter2), (void**)&m_pCAP2, TRUE);
m_pGB->FindInterface(__uuidof(IVMRWindowlessControl9), (void**)&m_pVMRWC, FALSE); // might have IVMRMixerBitmap9, but not IVMRWindowlessControl9
m_pGB->FindInterface(__uuidof(IVMRMixerControl9), (void**)&m_pVMRMC, TRUE);
m_pGB->FindInterface(__uuidof(IVMRMixerBitmap9), (void**)&pVMB, TRUE);
m_pGB->FindInterface(__uuidof(IMFVideoMixerBitmap), (void**)&pMFVMB, TRUE);
pMVTO = m_pCAP;

if (s.fShowOSD || s.fShowDebugInfo) { // Force OSD on when the debug switch is used
if (pVMB) {
m_OSD.Start(m_pVideoWnd, pVMB, IsD3DFullScreenMode());
} else if (pMFVMB) {
m_OSD.Start(m_pVideoWnd, pMFVMB, IsD3DFullScreenMode());
} else if (pMVTO) {
m_OSD.Start(m_pVideoWnd, pMVTO);
}
}
//VMR9
SetupVMR9ColorControl();

// === EVR !
m_pGB->FindInterface(__uuidof(IMFVideoDisplayControl), (void**)&m_pMFVDC,  TRUE);
m_pGB->FindInterface(__uuidof(IMFVideoProcessor), (void**)&m_pMFVP, TRUE);
if (m_pMFVDC) {
m_pMFVDC->SetVideoWindow(m_pVideoWnd->m_hWnd);
}

//SetupEVRColorControl();
//does not work at this location
//need to choose the correct mode (IMFVideoProcessor::SetVideoProcessorMode)

BeginEnumFilters(m_pGB, pEF, pBF) {
if (m_pLN21 = pBF) {
m_pLN21->SetServiceState(s.fClosedCaptions ? AM_L21_CCSTATE_On : AM_L21_CCSTATE_Off);
break;
}
}
EndEnumFilters;

if (m_fOpeningAborted) {
throw (UINT)IDS_AG_ABORTED;
}
//打开自定义的Graph
OpenCustomizeGraph();

if (m_fOpeningAborted) {
throw (UINT)IDS_AG_ABORTED;
}
//设置视频窗口
OpenSetupVideo();

if (m_fOpeningAborted) {
throw (UINT)IDS_AG_ABORTED;
}
//设置音量
OpenSetupAudio();

if (m_fOpeningAborted) {
throw (UINT)IDS_AG_ABORTED;
}

if (m_pCAP && (!m_fAudioOnly || m_fRealMediaGraph)) {

if (s.fDisableInternalSubtitles) {
m_pSubStreams.RemoveAll(); // Needs to be replaced with code that checks for forced subtitles.
}

m_posFirstExtSub = nullptr;
POSITION pos = pOMD->subs.GetHeadPosition();
while (pos) {
LoadSubtitle(pOMD->subs.GetNext(pos), nullptr, true);
}
}

if (m_fOpeningAborted) {
throw (UINT)IDS_AG_ABORTED;
}
//设置视频窗口标题
OpenSetupWindowTitle(pOMD->title);

if (s.fEnableEDLEditor) {
m_wndEditListEditor.OpenFile(pOMD->title);
}

if (::GetCurrentThreadId() == AfxGetApp()->m_nThreadID) {
OnFilePostOpenmedia();
} else {
PostMessage(WM_COMMAND, ID_FILE_POST_OPENMEDIA);
}

while (m_iMediaLoadState != MLS_LOADED
&& m_iMediaLoadState != MLS_CLOSING // FIXME
) {
Sleep(50);
}
//设置音频流
DWORD audstm = SetupAudioStreams();
//设置字幕流
DWORD substm = SetupSubtitleStreams();

if (audstm) {
OnPlayAudio(ID_AUDIO_SUBITEM_START + audstm);
}
if (substm) {
SetSubtitle(substm - 1);
}

// PostMessage instead of SendMessage because the user might call CloseMedia and then we would deadlock

PostMessage(WM_COMMAND, ID_PLAY_PAUSE);

m_bFirstPlay = true;

if (!(s.nCLSwitches & CLSW_OPEN) && (s.nLoops > 0)) {
PostMessage(WM_COMMAND, ID_PLAY_PLAY);
} else {
// If we don't start playing immediately, we need to initialize
// the seekbar and the time counter.
OnTimer(TIMER_STREAMPOSPOLLER);
OnTimer(TIMER_STREAMPOSPOLLER2);
}

s.nCLSwitches &= ~CLSW_OPEN;

if (pFileData) {
if (pFileData->rtStart > 0) {
PostMessage(WM_RESUMEFROMSTATE, (WPARAM)PM_FILE, (LPARAM)(pFileData->rtStart / 10000));  // REFERENCE_TIME doesn't fit in LPARAM under a 32bit env.
}
} else if (pDVDData) {
if (pDVDData->pDvdState) {
PostMessage(WM_RESUMEFROMSTATE, (WPARAM)PM_DVD, (LPARAM)(CComPtr<IDvdState>(pDVDData->pDvdState).Detach()));    // must be released by the called message handler
}
} else if (pDeviceData) {
m_wndCaptureBar.m_capdlg.SetVideoInput(pDeviceData->vinput);
m_wndCaptureBar.m_capdlg.SetVideoChannel(pDeviceData->vchannel);
m_wndCaptureBar.m_capdlg.SetAudioInput(pDeviceData->ainput);
}
} catch (LPCTSTR msg) {
err = msg;
} catch (CString& msg) {
err = msg;
} catch (UINT msg) {
err.LoadString(msg);
}

EndWaitCursor();

if (!err.IsEmpty()) {
//关闭
CloseMediaPrivate();
m_closingmsg = err;

if (err != ResStr(IDS_AG_ABORTED)) {
if (pFileData) {
m_wndPlaylistBar.SetCurValid(false);

if (m_wndPlaylistBar.IsAtEnd()) {
m_nLoops++;
}

if (s.fLoopForever || m_nLoops < s.nLoops) {
bool hasValidFile = false;

if (m_nLastSkipDirection == ID_NAVIGATE_SKIPBACK) {
hasValidFile = m_wndPlaylistBar.SetPrev();
} else {
hasValidFile = m_wndPlaylistBar.SetNext();
}

if (hasValidFile) {
OpenCurPlaylistItem();
}
} else if (m_wndPlaylistBar.GetCount() > 1) {
DoAfterPlaybackEvent();
}
} else {
OnNavigateSkip(ID_NAVIGATE_SKIPFORWARD);
}
}
} else {
m_wndPlaylistBar.SetCurValid(true);

// Apply command line audio shift
if (s.rtShift != 0) {
SetAudioDelay(s.rtShift);
s.rtShift = 0;
}
}

m_nLastSkipDirection = 0;

if (s.AutoChangeFullscrRes.bEnabled && (m_fFullScreen || IsD3DFullScreenMode())) {
AutoChangeMonitorMode();
}
if (m_fFullScreen && s.fRememberZoomLevel) {
m_fFirstFSAfterLaunchOnFS = true;
}

m_LastOpenFile = pOMD->title;

PostMessage(WM_KICKIDLE); // calls main thread to update things

if (!m_bIsBDPlay) {
m_MPLSPlaylist.RemoveAll();
m_LastOpenBDPath = _T("");
}
m_bIsBDPlay = false;

return err.IsEmpty();
}

来看一看OpenMediaPrivate()函数的细节：

1.开始的时候有这么一句

CAppSettings& s = AfxGetAppSettings();

在这里涉及到一个类CAppSettings，存储的是mpc-hc用到的各种设置信息。源代码如下：

//应用程序中的各种参数
class CAppSettings
{
bool fInitialized;

class CRecentFileAndURLList : public CRecentFileList
{
public:
CRecentFileAndURLList(UINT nStart, LPCTSTR lpszSection,
LPCTSTR lpszEntryFormat, int nSize,
int nMaxDispLen = AFX_ABBREV_FILENAME_LEN);

virtual void Add(LPCTSTR lpszPathName); // we have to override CRecentFileList::Add because the original version can't handle URLs
};

public:
bool fShaderEditorWasOpened;

// cmdline params
UINT nCLSwitches;
CAtlList<CString>   slFiles, slDubs, slSubs, slFilters;

// Initial position (used by command line flags)
REFERENCE_TIME      rtShift;
REFERENCE_TIME      rtStart;
ULONG               lDVDTitle;
ULONG               lDVDChapter;
DVD_HMSF_TIMECODE   DVDPosition;

CSize sizeFixedWindow;
bool HasFixedWindowSize() const { return sizeFixedWindow.cx > 0 || sizeFixedWindow.cy > 0; }
//int           iFixedWidth, iFixedHeight;
int             iMonitor;

CString         ParseFileName(CString const& param);
void            ParseCommandLine(CAtlList<CString>& cmdln);

// Added a Debug display to the screen (/debug option)
bool            fShowDebugInfo;
int             iAdminOption;

//播放器 Player
bool            fAllowMultipleInst;
bool            fTrayIcon;
bool            fShowOSD;
bool            fLimitWindowProportions;
bool            fSnapToDesktopEdges;
bool            fHideCDROMsSubMenu;
DWORD           dwPriority;
int             iTitleBarTextStyle;
bool            fTitleBarTextTitle;
bool            fKeepHistory;
CRecentFileAndURLList MRU;
CRecentFileAndURLList MRUDub;
CFilePositionList filePositions;
CDVDPositionList  dvdPositions;
bool            fRememberDVDPos;
bool            fRememberFilePos;
bool            bRememberPlaylistItems;
bool            fRememberWindowPos;
CRect           rcLastWindowPos;
bool            fRememberWindowSize;
bool            fSavePnSZoom;
double          dZoomX;
double          dZoomY;

// Formats
CMediaFormats   m_Formats;
bool            fAssociatedWithIcons;

// Keys
CList<wmcmd>    wmcmds;
HACCEL          hAccel;
bool            fWinLirc;
CString         strWinLircAddr;
CWinLircClient  WinLircClient;
bool            fUIce;
CString         strUIceAddr;
CUIceClient     UIceClient;
bool            fGlobalMedia;

//图标 Logo
UINT            nLogoId;
bool            fLogoExternal;
CString         strLogoFileName;

//web界面？ Web Inteface
BOOL            fEnableWebServer;
int             nWebServerPort;
int             nCmdlnWebServerPort;
bool            fWebServerUseCompression;
bool            fWebServerLocalhostOnly;
bool            fWebServerPrintDebugInfo;
CString         strWebRoot, strWebDefIndex;
CString         strWebServerCGI;

//播放时候 Playback
int             nVolume;
bool            fMute;
int             nBalance;
int             nLoops;
bool            fLoopForever;
bool            fRewind;
bool            fRememberZoomLevel;
int             nAutoFitFactor;
int             iZoomLevel;
CStringW        strAudiosLanguageOrder;
CStringW        strSubtitlesLanguageOrder;
bool            fEnableWorkerThreadForOpening;
bool            fReportFailedPins;
bool            fAutoloadAudio;
bool            fAutoloadSubtitles;
bool            fBlockVSFilter;
UINT            nVolumeStep;
UINT            nSpeedStep;

// DVD/OGM
bool            fUseDVDPath;
CString         strDVDPath;
LCID            idMenuLang, idAudioLang, idSubtitlesLang;
bool            fAutoSpeakerConf;
bool            fClosedCaptions;

//输出 Output
CRenderersSettings m_RenderersSettings;
int             iDSVideoRendererType;
int             iRMVideoRendererType;
int             iQTVideoRendererType;

CStringW        strAudioRendererDisplayName;
bool            fD3DFullscreen;

//全屏 Fullscreen
bool            fLaunchfullscreen;
bool            fShowBarsWhenFullScreen;
int             nShowBarsWhenFullScreenTimeOut;
bool            fExitFullScreenAtTheEnd;
CStringW        strFullScreenMonitor;
AChFR           AutoChangeFullscrRes;
bool            fRestoreResAfterExit;

// Sync Renderer Settings

// Capture (BDA configuration)
int             iDefaultCaptureDevice;      // Default capture device (analog=0, 1=digital)
CString         strAnalogVideo;
CString         strAnalogAudio;
int             iAnalogCountry;
CString         strBDANetworkProvider;
CString         strBDATuner;
CString         strBDAReceiver;
//CString           strBDAStandard;
int             iBDAScanFreqStart;
int             iBDAScanFreqEnd;
int             iBDABandwidth;
bool            fBDAUseOffset;
int             iBDAOffset;
bool            fBDAIgnoreEncryptedChannels;
UINT            nDVBLastChannel;
CAtlList<CDVBChannel> m_DVBChannels;
DVB_RebuildFilterGraph nDVBRebuildFilterGraph;
DVB_StopFilterGraph nDVBStopFilterGraph;

// Internal Filters
bool            SrcFilters[SRC_LAST + !SRC_LAST];
bool            TraFilters[TRA_LAST + !TRA_LAST];

//音频 Audio Switcher
bool            fEnableAudioSwitcher;
bool            fAudioNormalize;
UINT            nAudioMaxNormFactor;
bool            fAudioNormalizeRecover;
UINT            nAudioBoost;
bool            fDownSampleTo441;
bool            fAudioTimeShift;
int             iAudioTimeShift;
bool            fCustomChannelMapping;
int             nSpeakerChannels;
DWORD           pSpeakerToChannelMap[AS_MAX_CHANNELS][AS_MAX_CHANNELS];

// External Filters
CAutoPtrList<FilterOverride> m_filters;

//字幕 Subtitles
bool            fOverridePlacement;
int             nHorPos, nVerPos;
int             nSubDelayInterval;

// Default Style
STSStyle        subdefstyle;

// Misc
bool            bPreferDefaultForcedSubtitles;
bool            fPrioritizeExternalSubtitles;
bool            fDisableInternalSubtitles;
bool            bAllowOverridingExternalSplitterChoice;
CString         strSubtitlePaths;
CString         strISDb;

// Tweaks
int             nJumpDistS;
int             nJumpDistM;
int             nJumpDistL;
bool            fFastSeek;
bool            fShowChapters;
bool            bNotifySkype;
bool            fPreventMinimize;
bool            fUseWin7TaskBar;
bool            fLCDSupport;
bool            fUseSearchInFolder;
bool            fUseTimeTooltip;
int             nTimeTooltipPosition;
CString         strOSDFont;
int             nOSDSize;

//亮度色度饱和度 Miscellaneous
int             iBrightness;
int             iContrast;
int             iHue;
int             iSaturation;
int             nUpdaterAutoCheck;
int             nUpdaterDelay;

// MENUS
// View
int             iCaptionMenuMode; // normal -> hidemenu -> frameonly -> borderless
bool            fHideNavigation;
UINT            nCS; // Control state for toolbars
// Language
LANGID          language;
// Subtitles menu
bool            fEnableSubtitles;
bool            fUseDefaultSubtitlesStyle;
// Video Frame
int             iDefaultVideoSize;
bool            fKeepAspectRatio;
CSize           sizeAspectRatio;
bool            fCompMonDeskARDiff;
// Pan&Scan
CString         strPnSPreset;
CStringArray    m_pnspresets;
// On top menu
int             iOnTop;
// After Playback
bool            fExitAfterPlayback;
bool            fNextInDirAfterPlayback;

// WINDOWS
// Add Favorite
bool            bFavRememberPos;
bool            bFavRelativeDrive;
// Save Image...
CString         strSnapShotPath, strSnapShotExt;
// Save Thumbnails...
int             iThumbRows, iThumbCols, iThumbWidth;
// Shader Editor
struct Shader {
CString     label;
CString     target;
CString     srcdata;
};
CAtlList<Shader> m_shaders;
// Shader Combiner
bool            fToggleShader;
bool            fToggleShaderScreenSpace;
CString         strShaderList;
CString         strShaderListScreenSpace;
// Playlist (contex menu)
bool            bShufflePlaylistItems;
bool            bHidePlaylistFullScreen;

// OTHER STATES
CStringW        strLastOpenDir;
UINT            nLastWindowType;
UINT            nLastUsedPage;
bool            fRemainingTime;
bool            fLastFullScreen;

bool            fIntRealMedia;
//bool          fRealMediaRenderless;
//float         dRealMediaQuickTimeFPS;
//int           iVideoRendererType;
//int           iQuickTimeRenderer;
//bool          fMonitorAutoRefreshRate;
bool            fEnableEDLEditor;

HWND            hMasterWnd;

bool            IsD3DFullscreen() const;
CString         SelectedAudioRenderer() const;
bool            IsISREnabled() const;

private:
CString         SrcFiltersKeys[SRC_LAST + !SRC_LAST];
CString         TraFiltersKeys[TRA_LAST + !TRA_LAST];

__int64         ConvertTimeToMSec(const CString& time) const;
void            ExtractDVDStartPos(CString& strParam);

void            CreateCommands();

void            SaveExternalFilters(CAutoPtrList<FilterOverride>& filters, LPCTSTR baseKey = IDS_R_EXTERNAL_FILTERS);
void            LoadExternalFilters(CAutoPtrList<FilterOverride>& filters, LPCTSTR baseKey = IDS_R_EXTERNAL_FILTERS);
void            ConvertOldExternalFiltersList();

void            UpdateRenderersData(bool fSave);
friend void     CRenderersSettings::UpdateData(bool bSave);

public:
CAppSettings();
virtual ~CAppSettings();

void            SaveSettings();
void            LoadSettings();
void            SaveExternalFilters() { if (fInitialized) { SaveExternalFilters(m_filters); } };

void            GetFav(favtype ft, CAtlList<CString>& sl) const;
void            SetFav(favtype ft, CAtlList<CString>& sl);
void            AddFav(favtype ft, CString s);

CDVBChannel*    FindChannelByPref(int nPrefNumber);

bool            GetAllowMultiInst() const;

static bool     IsVSFilterInstalled();
static bool     HasEVR();
};

由代码可见，包含的参数信息很多。在mpc-hc中，任何需要获取设置信息的地方，都可以使用AfxGetAppSettings()获得CAppSettings的引用。

2.OpenSetupVideo()这个函数的作用是设置视频窗口，源代码如下：

//设置视频窗口
void CMainFrame::OpenSetupVideo()
{
//大部分都在确定：m_fAudioOnly是否为True
m_fAudioOnly = true;
//获得视频的宽和高，然后调整窗口大小
if (m_pMFVDC) { // EVR
m_fAudioOnly = false;
} else if (m_pCAP) {
CSize vs = m_pCAP->GetVideoSize();
m_fAudioOnly = (vs.cx <= 0 || vs.cy <= 0);
} else {
{
long w = 0, h = 0;

if (CComQIPtr<IBasicVideo> pBV = m_pGB) {
pBV->GetVideoSize(&w, &h);
}

if (w > 0 && h > 0) {
m_fAudioOnly = false;
}
}
//如果 m_fAudioOnly=true；再检查
if (m_fAudioOnly) {
BeginEnumFilters(m_pGB, pEF, pBF) {
long w = 0, h = 0;

if (CComQIPtr<IVideoWindow> pVW = pBF) {
long lVisible;
if (FAILED(pVW->get_Visible(&lVisible))) {
continue;
}

pVW->get_Width(&w);
pVW->get_Height(&h);
}

if (w > 0 && h > 0) {
m_fAudioOnly = false;
break;
}
}
EndEnumFilters;
}
}

if (m_fShockwaveGraph) {
m_fAudioOnly = false;
}

if (m_pCAP) {
SetShaders();
}
// else
{
// TESTME
//设置所有者。。。
m_pVW->put_Owner((OAHWND)m_pVideoWnd->m_hWnd);
m_pVW->put_WindowStyle(WS_CHILD | WS_CLIPSIBLINGS | WS_CLIPCHILDREN);
m_pVW->put_MessageDrain((OAHWND)m_hWnd);

for (CWnd* pWnd = m_wndView.GetWindow(GW_CHILD); pWnd; pWnd = pWnd->GetNextWindow()) {
pWnd->EnableWindow(FALSE);    // little trick to let WM_SETCURSOR thru
}
}
//如果只有音频，则消灭视频窗口！
if (m_fAudioOnly && IsD3DFullScreenMode()) {
m_pFullscreenWnd->DestroyWindow();
}
}

3.
OpenSetupAudio()这个函数的作用是设置音频，源代码如下：

//设置音量
void CMainFrame::OpenSetupAudio()
{
//设置音量
m_pBA->put_Volume(m_wndToolBar.Volume);

// FIXME
int balance = AfxGetAppSettings().nBalance;

int sign = balance > 0 ? -1 : 1; // -1: invert sign for more right channel
if (balance > -100 && balance < 100) {
balance = sign * (int)(100 * 20 * log10(1 - abs(balance) / 100.0f));
} else {
balance = sign * (-10000);  // -10000: only left, 10000: only right
}
//设置均衡
m_pBA->put_Balance(balance);
}

4.如果出现问题，则会调用CloseMediaPrivate()，关闭打开的媒体。

//关闭
void CMainFrame::CloseMediaPrivate()
{
SetLoadState(MLS_CLOSING); // why it before OnPlayStop()? // TODO: remake or add detailed comments
OnPlayStop(); // SendMessage(WM_COMMAND, ID_PLAY_STOP);
if (m_pMC) {
m_pMC->Stop(); // needed for StreamBufferSource, because m_iMediaLoadState is always MLS_CLOSED // TODO: fix the opening for such media
}
SetPlaybackMode(PM_NONE);
m_fLiveWM = false;
m_fEndOfStream = false;
m_rtDurationOverride = -1;
m_kfs.RemoveAll();
m_pCB.Release();

{
CAutoLock cAutoLock(&m_csSubLock);
m_pSubStreams.RemoveAll();
}
m_pSubClock.Release();

//if (m_pVW) m_pVW->put_Visible(OAFALSE);
//if (m_pVW) m_pVW->put_MessageDrain((OAHWND)NULL), m_pVW->put_Owner((OAHWND)NULL);

// IMPORTANT: IVMRSurfaceAllocatorNotify/IVMRSurfaceAllocatorNotify9 has to be released before the VMR/VMR9, otherwise it will crash in Release()
//各种清空
m_OSD.Stop();
m_pCAP2.Release();
m_pCAP.Release();
m_pVMRWC.Release();
m_pVMRMC.Release();
m_pMFVP.Release();
m_pMFVDC.Release();
m_pLN21.Release();
m_pSyncClock.Release();

m_pAMXBar.Release();
m_pAMDF.Release();
m_pAMVCCap.Release();
m_pAMVCPrev.Release();
m_pAMVSCCap.Release();
m_pAMVSCPrev.Release();
m_pAMASC.Release();
m_pVidCap.Release();
m_pAudCap.Release();
m_pAMTuner.Release();
m_pCGB.Release();

m_pDVDC.Release();
m_pDVDI.Release();
m_pAMOP.Release();
m_pBI.Release();
m_pQP.Release();
m_pFS.Release();
m_pMS.Release();
m_pBA.Release();
m_pBV.Release();
m_pVW.Release();
m_pME.Release();
m_pMC.Release();

if (m_pGB) {
m_pGB->RemoveFromROT();
m_pGB.Release();
}

m_pProv.Release();

m_fRealMediaGraph = m_fShockwaveGraph = m_fQuicktimeGraph = false;

m_VidDispName.Empty();
m_AudDispName.Empty();

m_closingmsg.LoadString(IDS_CONTROLS_CLOSED);

AfxGetAppSettings().nCLSwitches &= CLSW_OPEN | CLSW_PLAY | CLSW_AFTERPLAYBACK_MASK | CLSW_NOFOCUS;
//设置状态
SetLoadState(MLS_CLOSED);
}