Simple Play Application for C++

// include the LEAD Multimedia TOOLKIT header 
#include "ltmm.h" 
#include "resource.h" 
#include <tchar.h> 
#include <stdio.h> 
#include <math.h> 
#define SZ_WNDCLASS_PLAY _T("PLAY WNDCLASS") 
#define WM_PLAYNOTIFY (WM_USER + 1000) 
 
HINSTANCE g_hInstance; // application instance handle 
HWND g_hwndPlay;  // video frame window 
IltmmPlay* g_pPlay;  // play object interface pointer 
int g_nPositionView;  // current position indicator view mode 
enum 
{ 
   POSITIONVIEW_TIME, 
   POSITIONVIEW_FRAME, 
   POSITIONVIEW_TRACKING 
}; 
// 
// SnapFrameToVideo 
// resizes the frame window to match the video width and height 
// 
void SnapFrameToVideo(void) 
{ 
   HWND hwnd; 
   RECT rcWindow, rcClient; 
   long cx, cy; 
   // get the frame window 
   g_pPlay->get_VideoWindowFrame((long*) &hwnd); 
   // get the video dimensions 
   g_pPlay->get_VideoWidth(&cx); 
   g_pPlay->get_VideoHeight(&cy); 
   // adjust by the border dimensions 
   GetWindowRect(hwnd, &rcWindow); 
   GetClientRect(hwnd, &rcClient); 
   cx += ((rcWindow.right - rcWindow.left) - (rcClient.right - rcClient.left)); 
   cy += ((rcWindow.bottom - rcWindow.top) - (rcClient.bottom - rcClient.top)); 
   // resize the window 
   SetWindowPos(hwnd, NULL, 0, 0, cx, cy, SWP_NOMOVE | SWP_NOZORDER); 
} 
// 
// FreeSource 
// resets source and frees asssociated resources 
// 
void FreeSource(void) 
{ 
   long type; 
   VARIANT var; 
   HGLOBAL hglobal; 
   g_pPlay->get_SourceType(&type); 
   if(type == ltmmPlay_Source_Array) 
   { 
      g_pPlay->get_SourceArray(&var); 
      g_pPlay->ResetSource(); 
      VariantClear(&var); 
   } 
   else if(type == ltmmPlay_Source_HGlobal) 
   { 
      g_pPlay->get_SourceHGlobal((long*) &hglobal); 
      g_pPlay->ResetSource(); 
      GlobalFree(hglobal); 
   } 
   else 
   { 
      g_pPlay->ResetSource(); 
   } 
} 
// 
// SetSourceArray 
// preloads a SAFEARRAY with media data and assigns it to the play object 
// 
void SetSourceArray(void) 
{ 
   HRESULT hr; 
   HANDLE hfile; 
   DWORD size, cb; 
   void* buffer; 
   VARIANT var; 
   SAFEARRAY* psaSource; 
    
   // open the source file 
   hfile = CreateFile(MAKE_MEDIA_PATH("source.avi"), GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, 0, NULL); 
   if(hfile == INVALID_HANDLE_VALUE) 
      return; 
    
   // allocate same-sized SAFEARRAY 
   size = GetFileSize(hfile, NULL); 
   psaSource = SafeArrayCreateVector(VT_UI1, 0, size); 
   if(!psaSource) 
   { 
      CloseHandle(hfile); 
      return; 
   } 
   // read entire source into array 
   SafeArrayAccessData(psaSource, (void**) &buffer); 
   if(!ReadFile(hfile, buffer, size, &cb, NULL) || cb != size) 
   { 
      SafeArrayUnaccessData(psaSource); 
      CloseHandle(hfile); 
      SafeArrayDestroy(psaSource); 
      return; 
   } 
   SafeArrayUnaccessData(psaSource); 
   // close file 
   CloseHandle(hfile); 
   // assign the source array 
   VariantInit(&var); 
   V_VT(&var) = (VT_ARRAY | VT_UI1); 
   V_ARRAY(&var) = psaSource; 
   hr = g_pPlay->put_SourceArray(var); 
   if(FAILED(hr)) 
   { 
      SafeArrayDestroy(psaSource); 
      return; 
   } 
} 
// 
// SetSourceArray 
// preloads global memory with media data and assigns it to the play object 
// 
void SetSourceHGlobal(void) 
{ 
   HRESULT hr; 
   HANDLE hfile; 
   DWORD size, cb; 
   void* buffer; 
   HGLOBAL hglobal; 
   // open the source file 
   hfile = CreateFile(MAKE_MEDIA_PATH("source.avi"), GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, 0, NULL); 
   if(hfile == INVALID_HANDLE_VALUE) 
      return; 
   // allocate same-sized global memory 
   size = GetFileSize(hfile, NULL); 
   hglobal = GlobalAlloc(GMEM_MOVEABLE, size); 
   if(!hglobal) 
   {   
      CloseHandle(hfile); 
      return; 
   } 
   // read entire source into memory 
   buffer = GlobalLock(hglobal); 
   if(!ReadFile(hfile, buffer, size, &cb, NULL) || cb != size) 
   {   
      GlobalUnlock(hglobal); 
      CloseHandle(hfile); 
      GlobalFree(hglobal); 
      return; 
   } 
   GlobalUnlock(hglobal); 
   // close file 
   CloseHandle(hfile); 
   hr = g_pPlay->put_SourceHGlobal((long) hglobal); 
   if(FAILED(hr)) 
   {   
      GlobalFree(hglobal); 
      return; 
   } 
} 
// 
// PlayWndProc 
// video frame window procedure 
// 
LRESULT CALLBACK PlayWndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam) 
{ 
   BSTR bstr; 
   VARIANT_BOOL f; 
   long l; 
   TCHAR sz[2048]; 
   LPTSTR p; 
   double d; 
   HRESULT hr; 
   ltmmSizeMode sm; 
   long x, y, cx, cy; 
   RECT rc; 
   POINT pt; 
   HGLOBAL hDIB; 
   IPictureDisp* pPictureDisp; 
   switch (message) 
   {   case WM_CREATE: 
   g_hwndPlay = hwnd; 
   // window is the video window frame 
   g_pPlay->put_VideoWindowFrame((long) hwnd); 
   // want notification messages as well 
   g_pPlay->SetNotifyWindow((long) hwnd, WM_PLAYNOTIFY); 
   // make sure we start playing immediately 
   g_pPlay->put_AutoStart(VARIANT_TRUE); 
   // set the source file 
   bstr = SysAllocString(MAKE_MEDIA_PATH("source.avi")); 
   hr = g_pPlay->put_SourceFile(bstr); 
   SysFreeString(bstr); 
   if(SUCCEEDED(hr)) 
   {   
      g_pPlay->get_UnrenderedStreams(&l); 
      if(l != 0) 
         MessageBox(hwnd, _T("Not all the streams could be rendered."), _T("Play"), MB_ICONEXCLAMATION | MB_OK); 
   }   
   SnapFrameToVideo(); 
   return 0; 
   break; 
   case WM_INITMENUPOPUP: 
      if(GetSubMenu(GetMenu(hwnd), 0) == (HMENU)wParam) 
      {   
         // enable menu items based on the play object state 
         g_pPlay->get_State(&l); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_PLAY, (l == ltmmPlay_State_Paused || l == ltmmPlay_State_Stopped) ? MF_ENABLED : MF_GRAYED); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_PAUSE, (l == ltmmPlay_State_Running) ? MF_ENABLED : MF_GRAYED); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_STOP, (l == ltmmPlay_State_Running || l == ltmmPlay_State_Paused) ? MF_ENABLED : MF_GRAYED); 
         // enable menu items based on seeking capabilities 
         g_pPlay->CheckSeekingCapabilities(ltmmPlay_Seeking_Forward | ltmmPlay_Seeking_Backward | ltmmPlay_Seeking_FrameForward | ltmmPlay_Seeking_FrameBackward, &l); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_SEEKSTART, (l & ltmmPlay_Seeking_Backward) ? MF_ENABLED : MF_GRAYED); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_SEEKEND, (l & ltmmPlay_Seeking_Forward) ? MF_ENABLED : MF_GRAYED); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_NEXTFRAME, (l & ltmmPlay_Seeking_FrameForward) ? MF_ENABLED : MF_GRAYED); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_PREVIOUSFRAME, (l & ltmmPlay_Seeking_FrameBackward) ? MF_ENABLED : MF_GRAYED); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_SEEKSELECTIONSTART, (l & (ltmmPlay_Seeking_Forward | ltmmPlay_Seeking_Backward)) ? MF_ENABLED : MF_GRAYED); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_SEEKSELECTIONEND, (l & (ltmmPlay_Seeking_Forward | ltmmPlay_Seeking_Backward)) ? MF_ENABLED : MF_GRAYED); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_LASTFRAME, (l & ltmmPlay_Seeking_FrameForward) ? MF_ENABLED : MF_GRAYED); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_FIRSTFRAME, (l & ltmmPlay_Seeking_FrameBackward) ? MF_ENABLED : MF_GRAYED); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_STEPFORWARD1SEC, (l & ltmmPlay_Seeking_Forward) ? MF_ENABLED : MF_GRAYED); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_STEPFORWARD10, (l & ltmmPlay_Seeking_Forward) ? MF_ENABLED : MF_GRAYED); 
         // check the current speed 
         g_pPlay->get_Rate(&d); 
         CheckMenuItem((HMENU) wParam, ID_CONTROL_HALFSPEED, (fabs(d - 0.5) < 0.1) ? MF_CHECKED : MF_UNCHECKED); 
         CheckMenuItem((HMENU) wParam, ID_CONTROL_NORMALSPEED, (fabs(d - 1.0) < 0.1) ? MF_CHECKED : MF_UNCHECKED); 
         // check the current video size mode 
         g_pPlay->get_VideoWindowSizeMode(&sm); 
         CheckMenuItem((HMENU) wParam, ID_CONTROL_FITTOWINDOW, (sm == ltmmFit) ? MF_CHECKED : MF_UNCHECKED); 
         CheckMenuItem((HMENU) wParam, ID_CONTROL_STRETCHTOWINDOW, (sm == ltmmStretch) ? MF_CHECKED : MF_UNCHECKED); 
         // enable volume menu items 
         g_pPlay->get_Volume(&l); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_INCREASEVOLUME, (l < 0) ? MF_ENABLED : MF_GRAYED); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_DECREASEVOLUME, (l > -10000) ? MF_ENABLED : MF_GRAYED); 
         // enable balance menu items 
         g_pPlay->get_Balance(&l); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_PANRIGHT, (l < 10000) ? MF_ENABLED : MF_GRAYED); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_PANLEFT, (l > -10000) ? MF_ENABLED : MF_GRAYED); 
         // check mute 
         g_pPlay->get_Mute(&f); 
         CheckMenuItem((HMENU) wParam, ID_CONTROL_MUTE, f ? MF_CHECKED : MF_UNCHECKED); 
         // check auto rewind 
         g_pPlay->get_AutoRewind(&f); 
         CheckMenuItem((HMENU) wParam, ID_CONTROL_AUTOREWIND, f ? MF_CHECKED : MF_UNCHECKED); 
         // check loop 
         g_pPlay->get_PlayCount(&l); 
         CheckMenuItem((HMENU) wParam, ID_CONTROL_LOOP, (l == 0) ? MF_CHECKED : MF_UNCHECKED); 
         // enable processors 
         g_pPlay->HasDialog(ltmmPlay_Dlg_VideoProcessors, &f); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_PROCESSORS_VIDEO, f ? MF_ENABLED : MF_GRAYED); 
         g_pPlay->HasDialog(ltmmPlay_Dlg_AudioProcessors, &f); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_PROCESSORS_AUDIO, f ? MF_ENABLED : MF_GRAYED); 
         // check source 
         g_pPlay->get_SourceType(&l); 
         CheckMenuItem((HMENU) wParam, ID_CONTROL_SOURCE_FILE, (l == ltmmPlay_Source_File) ? MF_CHECKED : MF_UNCHECKED); 
         CheckMenuItem((HMENU) wParam, ID_CONTROL_SOURCE_ARRAY, (l == ltmmPlay_Source_Array) ? MF_CHECKED : MF_UNCHECKED); 
         CheckMenuItem((HMENU) wParam, ID_CONTROL_SOURCE_HGLOBAL, (l == ltmmPlay_Source_HGlobal) ? MF_CHECKED : MF_UNCHECKED); 
         g_pPlay->get_AutoStart(&f); 
         CheckMenuItem((HMENU) wParam, ID_CONTROL_AUTOSTART, f ? MF_CHECKED : MF_UNCHECKED); 
         // check position view 
         CheckMenuItem((HMENU) wParam, ID_CONTROL_POSITIONVIEW_FRAME, (g_nPositionView == POSITIONVIEW_FRAME) ? MF_CHECKED : MF_UNCHECKED); 
         CheckMenuItem((HMENU) wParam, ID_CONTROL_POSITIONVIEW_TIME, (g_nPositionView == POSITIONVIEW_TIME) ? MF_CHECKED : MF_UNCHECKED); 
         CheckMenuItem((HMENU) wParam, ID_CONTROL_POSITIONVIEW_TRACKING, (g_nPositionView == POSITIONVIEW_TRACKING) ? MF_CHECKED : MF_UNCHECKED); 
         // enable still options 
         g_pPlay->get_RenderedStreams(&l); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_COPYDIB, (l & ltmmPlay_Stream_Video) ? MF_ENABLED : MF_GRAYED); 
         EnableMenuItem((HMENU) wParam, ID_CONTROL_SAVEPICTURE, (l & ltmmPlay_Stream_Video) ? MF_ENABLED : MF_GRAYED); 
      }   
      break; 
   case WM_PLAYNOTIFY: 
      switch(wParam) 
      {   
      case ltmmPlay_Notify_TrackingSelectionChanged: 
         break; 
      case ltmmPlay_Notify_TrackingPositionChanged: 
         p = sz; 
         *p = _T('\0'); 
         g_pPlay->get_RenderedStreams(&l); 
         if((l & ltmmPlay_Stream_Audio) && !(l & ltmmPlay_Stream_Video)) 
         {   
            // audio only stream 
            if(p != sz) 
               p += _stprintf(p, _T(", ")); 
            p += _stprintf(p, _T("Audio")); 
         }   
         else if(l & ltmmPlay_Stream_Midi) 
         {   
            // midi stream 
            if(p != sz) 
               p += _stprintf(p, _T(", ")); 
            p += _stprintf(p, _T("Midi")); 
         }   
         if(g_nPositionView == POSITIONVIEW_TRACKING)// tracking position based 
         {   
            // display current tracking position 
            hr = g_pPlay->get_CurrentTrackingPosition(&l); 
            if(SUCCEEDED(hr)) 
            {   
               if(p != sz) 
                  p += _stprintf(p, _T(", ")); 
               p += _stprintf(p, _T("Trk. Pos.: %d"), l); 
            }   
            // display current tracking selection start 
            hr = g_pPlay->get_TrackingSelectionStart(&l); 
            if(SUCCEEDED(hr)) 
            {   
               if(p != sz) 
                  p += _stprintf(p, _T(", ")); 
               p += _stprintf(p, _T("Trk. Start: %d"), l); 
            }   
            // display current tracking selection end 
            hr= g_pPlay->get_TrackingSelectionEnd(&l); 
            if(SUCCEEDED(hr)) 
            {   
               if(p != sz) 
                  p += _stprintf(p, _T(", ")); 
               p += _stprintf(p, _T("Trk. End: %d"), l); 
            }   
         }   
         else if(g_nPositionView == POSITIONVIEW_FRAME)// frame based 
         {   
            // display current frame position 
            hr = g_pPlay->get_CurrentFramePosition(&l); 
            if(SUCCEEDED(hr)) 
            {   
               if(p != sz) 
                  p += _stprintf(p, _T(", ")); 
               p += _stprintf(p, _T("Frame: %d"), l + 1); 
            }   
            // display total number of frames 
            hr = g_pPlay->get_FrameDuration(&l); 
            if(SUCCEEDED(hr)) 
            {   
               if(p != sz) 
                  p += _stprintf(p, _T(", ")); 
               p += _stprintf(p, _T("Total Frames: %d"), l); 
            }   
         }   
         else // time based 
         {   
            // display the current position 
            hr = g_pPlay->get_CurrentPosition(&d); 
            if(SUCCEEDED(hr)) 
            {   
               if(p != sz) 
                  p += _stprintf(p, _T(", ")); 
               p += _stprintf(p, _T("Position: %f"), d); 
            }   
            // display the total duration 
            hr = g_pPlay->get_Duration(&d); 
            if(SUCCEEDED(hr)) 
            {   
               if(p != sz) 
                  p += _stprintf(p, _T(", ")); 
               p += _stprintf(p, _T("Duration: %f"), d); 
            }   
            // display current selection start 
            hr = g_pPlay->get_SelectionStart(&d); 
            if(SUCCEEDED(hr)) 
            {   
               if(p != sz) 
                  p += _stprintf(p, _T(", ")); 
               p += _stprintf(p, _T("Start: %f"), d); 
            }   
            // display current selection end 
            hr = g_pPlay->get_SelectionEnd(&d); 
            if(SUCCEEDED(hr)) 
            {   
               if(p != sz) 
                  p += _stprintf(p, _T(", ")); 
               p += _stprintf(p, _T("End: %f"), d); 
            }   
         }   
         SetWindowText(hwnd, sz); 
         break; 
 
      case ltmmPlay_Notify_StateChanged: 
         switch(LOWORD(lParam)) 
         {   
         case ltmmPlay_State_NotReady: 
            _stprintf(sz, _T("Not Ready")); 
            SetWindowText(hwnd, sz); 
            break; 
         case ltmmPlay_State_Stopped: 
            // uncomment the following line to view the graph in DirectShow GraphEdit 
            // g_pPlay->EditGraph(); 
            g_pPlay->get_SourceType(&l); 
            if(l == ltmmPlay_Source_Array) 
            {   
               _stprintf(sz, _T("Stopped - [array]")); 
            }   
            else if(l == ltmmPlay_Source_HGlobal) 
            {   
               _stprintf(sz, _T("Stopped - [hglobal]")); 
            }   
            else 
            {   
               g_pPlay->get_SourceFile(&bstr); 
               _stprintf(sz, _T("Stopped - [%ls]"), bstr); 
               SysFreeString(bstr); 
            }   
            SetWindowText(hwnd, sz); 
            break; 
         case ltmmPlay_State_Paused: 
            g_pPlay->get_SourceType(&l); 
            if(l == ltmmPlay_Source_Array) 
            {   
               _stprintf(sz, _T("Paused - [array]")); 
            }   
            else if(l == ltmmPlay_Source_HGlobal) 
            {   
               _stprintf(sz, _T("Paused - [hglobal]")); 
            }   
            else 
            {   
               g_pPlay->get_SourceFile(&bstr); 
               _stprintf(sz, _T("Paused - [%ls]"), bstr); 
               SysFreeString(bstr); 
            }   
            SetWindowText(hwnd, sz); 
            break; 
         case ltmmPlay_State_Running: 
            _stprintf(sz, _T("Playing")); 
            SetWindowText(hwnd, sz); 
            break; 
         }   
         break; 
      case ltmmPlay_Notify_Error: 
         _stprintf(sz, _T("Error 0x%.8X. Playback stopped."), lParam); 
         MessageBox(hwnd, sz, _T("Play"), MB_ICONEXCLAMATION | MB_OK); 
         break; 
      } 
      return 0; 
      break; 
   case WM_KEYDOWN: 
      if(wParam == VK_ESCAPE) 
      {   
         // if fullscreen mode then exit it 
         g_pPlay->get_FullScreenMode(&f); 
         if(f) 
         {   
            g_pPlay->put_FullScreenMode(VARIANT_FALSE); 
            return 0; 
         }   
      }   
      break; 
   case WM_DESTROY: 
      FreeSource(); 
      // no more notifications 
      g_pPlay->SetNotifyWindow((long) NULL, 0); 
      PostQuitMessage(0); 
      break; 
   case WM_COMMAND: 
      switch(LOWORD(wParam)) 
      {   
      case ID_CONTROL_POSITIONVIEW_TIME: 
         g_nPositionView = POSITIONVIEW_TIME; 
         break; 
      case ID_CONTROL_POSITIONVIEW_FRAME: 
         g_nPositionView = POSITIONVIEW_FRAME; 
         break; 
      case ID_CONTROL_POSITIONVIEW_TRACKING: 
         g_nPositionView = POSITIONVIEW_TRACKING; 
         break; 
      case ID_CONTROL_AUTOSTART: 
         // toggle auto start 
         g_pPlay->get_AutoStart(&f); 
         g_pPlay->put_AutoStart(f ? VARIANT_FALSE : VARIANT_TRUE); 
         return 0; 
         break; 
      case ID_CONTROL_PLAY: 
         // play file 
         g_pPlay->Run(); 
         return 0; 
         break; 
      case ID_CONTROL_PAUSE: 
         // pause playback 
         g_pPlay->Pause(); 
         return 0; 
         break; 
      case ID_CONTROL_STOP: 
         // stop playback 
         g_pPlay->Stop(); 
         return 0; 
         break; 
      case ID_CONTROL_HALFSPEED: 
         // set to half the normal playback speed 
         g_pPlay->put_Rate(0.5); 
         return 0; 
         break; 
      case ID_CONTROL_NORMALSPEED: 
         // set to normal speed 
         g_pPlay->put_Rate(1.0); 
         return 0; 
         break; 
      case ID_CONTROL_SEEKSTART: 
         // seek to file start 
         g_pPlay->SeekStart(); 
         return 0; 
         break; 
      case ID_CONTROL_SEEKEND: 
         // seek to file end 
         g_pPlay->SeekEnd(); 
         return 0; 
         break; 
      case ID_CONTROL_SEEKSELECTIONSTART: 
         // seek to the start of the current selection 
         g_pPlay->SeekSelectionStart(); 
         return 0; 
         break; 
      case ID_CONTROL_SEEKSELECTIONEND: 
         // seek to the end of the current selection 
         g_pPlay->SeekSelectionEnd(); 
         return 0; 
         break; 
      case ID_CONTROL_SETSELECTIONSTART: 
         // set the start of the selection to the current position 
         g_pPlay->MarkSelectionStart(); 
         return 0; 
         break; 
      case ID_CONTROL_SETSELECTIONEND: 
         // set the end of the selection to the current position 
         g_pPlay->MarkSelectionEnd(); 
         return 0; 
         break; 
      case ID_CONTROL_CLEARSELECTION: 
         // clear the current selection 
         g_pPlay->get_Duration(&d); 
         g_pPlay->put_SelectionStart(0.0); 
         g_pPlay->put_SelectionEnd(d); 
         return 0; 
         break; 
      case ID_CONTROL_NEXTFRAME: 
         // goto the next frame 
         g_pPlay->NextFrame(); 
         return 0; 
         break; 
      case ID_CONTROL_PREVIOUSFRAME: 
         // goto the previous frame 
         g_pPlay->PreviousFrame(); 
         return 0; 
         break; 
      case ID_CONTROL_FIRSTFRAME: 
         // goto to the first frame 
         g_pPlay->put_CurrentFramePosition(0); 
         return 0; 
         break; 
      case ID_CONTROL_LASTFRAME: 
         // goto to the last frame 
         g_pPlay->get_FrameDuration(&l); 
         g_pPlay->put_CurrentFramePosition(l - 1); 
         return 0; 
         break; 
      case ID_CONTROL_STEPFORWARD1SEC: 
         // step forward 1 seconds 
         g_pPlay->get_CurrentPosition(&d); 
         g_pPlay->put_CurrentPosition(d + 1.0); 
         return 0; 
         break; 
      case ID_CONTROL_STEPFORWARD10: 
         // step forward 10% 
         g_pPlay->get_CurrentTrackingPosition(&l); 
         g_pPlay->put_CurrentTrackingPosition(l + 1000); 
         return 0; 
         break; 
      case ID_CONTROL_FITTOWINDOW: 
         // fit the video to the window 
         g_pPlay->put_VideoWindowSizeMode(ltmmFit); 
         return 0; 
         break; 
      case ID_CONTROL_STRETCHTOWINDOW: 
         // stretch the video to the window 
         g_pPlay->put_VideoWindowSizeMode(ltmmStretch); 
         return 0; 
         break; 
      case ID_CONTROL_MUTE: 
         // toggle mute 
         g_pPlay->get_Mute(&f); 
         g_pPlay->put_Mute(f ? VARIANT_FALSE : VARIANT_TRUE); 
         return 0; 
         break; 
      case ID_CONTROL_INCREASEVOLUME: 
         // increase the volume 
         g_pPlay->get_Volume(&l); 
         g_pPlay->put_Volume(min(0, l + 300)); 
         return 0; 
         break; 
      case ID_CONTROL_DECREASEVOLUME: 
         // decrease the volume 
         g_pPlay->get_Volume(&l); 
         g_pPlay->put_Volume(max(-10000, l - 300)); 
         return 0; 
         break; 
      case ID_CONTROL_PANRIGHT: 
         // pan balance to the right 
         g_pPlay->get_Balance(&l); 
         g_pPlay->put_Balance(min(10000, l + 300)); 
         return 0; 
         break; 
      case ID_CONTROL_PANLEFT: 
         // pan balance to the left 
         g_pPlay->get_Balance(&l); 
         g_pPlay->put_Balance(max(-10000, l - 300)); 
         return 0; 
         break; 
      case ID_CONTROL_LOOP: 
         // toggle looping 
         g_pPlay->get_PlayCount(&l); 
         g_pPlay->put_PlayCount(l ? 0 : 1); 
         return 0; 
         break; 
      case ID_CONTROL_FULLSCREEN: 
         // togglr fullscreen mode 
         g_pPlay->ToggleFullScreenMode(); 
         return 0; 
         break; 
      case ID_CONTROL_AUTOREWIND: 
         // toggle auto rewind 
         g_pPlay->get_AutoRewind(&f); 
         g_pPlay->put_AutoRewind(f ? VARIANT_FALSE : VARIANT_TRUE); 
         return 0; 
         break; 
      case ID_CONTROL_PROCESSORS_VIDEO: 
         // invoke video processor dialog box 
         g_pPlay->ShowDialog(ltmmPlay_Dlg_VideoProcessors, (long) hwnd); 
         return 0; 
         break; 
      case ID_CONTROL_PROCESSORS_AUDIO: 
         // invoke audio processor dialog box 
         g_pPlay->ShowDialog(ltmmPlay_Dlg_AudioProcessors, (long) hwnd); 
         return 0; 
         break; 
      case ID_CONTROL_SOURCE_FILE: 
         // set the source file 
         FreeSource(); 
         bstr = SysAllocString(MAKE_MEDIA_PATH("source.avi")); 
         g_pPlay->put_SourceFile(bstr); 
         SysFreeString(bstr); 
         SnapFrameToVideo(); 
         return 0; 
         break; 
      case ID_CONTROL_SOURCE_ARRAY: 
         // set the source array 
         FreeSource(); 
         SetSourceArray(); 
         SnapFrameToVideo(); 
         return 0; 
         break; 
      case ID_CONTROL_SOURCE_HGLOBAL: 
         // set the source hglobal 
         FreeSource(); 
         SetSourceHGlobal(); 
         SnapFrameToVideo(); 
         return 0; 
         break; 
      case ID_CONTROL_MEDIAINFORMATION: 
         // display available media information 
         p = sz; 
         g_pPlay->get_Title(&bstr); 
         p += _stprintf(p, _T("Title = '%ls'"), bstr ? bstr : L""); 
         SysFreeString(bstr); 
         g_pPlay->get_Author(&bstr); 
         p += _stprintf(p, _T(", Author = '%ls'"), bstr ? bstr : L""); 
         SysFreeString(bstr); 
         g_pPlay->get_Copyright(&bstr); 
         p += _stprintf(p, _T(", Copyright = '%ls'"), bstr ? bstr : L""); 
         SysFreeString(bstr); 
         g_pPlay->get_Description(&bstr); 
         p += _stprintf(p, _T(", Description = '%ls'"), bstr ? bstr : L""); 
         SysFreeString(bstr); 
         g_pPlay->get_Rating(&bstr); 
         p += _stprintf(p, _T(", Rating = '%ls'"), bstr ? bstr : L""); 
         SysFreeString(bstr); 
         MessageBox(hwnd, sz, _T("Media Information"), MB_OK); 
         return 0; 
         break; 
      case ID_CONTROL_COPYDIB: 
         // device independent bitmap 
         hr = g_pPlay->GetStillDIB(5000, (long*) &hDIB); 
         if(SUCCEEDED(hr)) 
         {   
            // copy to the clipboard 
            OpenClipboard(hwnd); 
            EmptyClipboard(); 
            SetClipboardData(CF_DIB, hDIB); 
            CloseClipboard(); 
         }   
         return 0; 
         break; 
      case ID_CONTROL_SAVEPICTURE: 
         // ole picture object 
         hr = g_pPlay->GetStillPicture(5000, &pPictureDisp); 
         if(SUCCEEDED(hr)) 
         {   
            // save the picture 
            bstr = SysAllocString(MAKE_MEDIA_PATH("still.bmp")); 
            OleSavePictureFile(pPictureDisp, bstr); 
            SysFreeString(bstr); 
            pPictureDisp->Release(); 
         }   
         return 0; 
         break; 
      } 
      break; 
   case WM_LBUTTONDOWN: 
      // perform play/pause if the user clicks in the video window 
      g_pPlay->get_VideoWindowLeft(&x); 
      g_pPlay->get_VideoWindowTop(&y); 
      g_pPlay->get_VideoWindowWidth(&cx); 
      g_pPlay->get_VideoWindowHeight(&cy); 
      SetRect(&rc, x, y, x + cx, y + cy); 
      pt.x = (short) LOWORD(lParam); 
      pt.y = (short) HIWORD(lParam); 
      if(PtInRect(&rc, pt)) 
      {   
         g_pPlay->get_State(&l); 
         if(l == ltmmPlay_State_Stopped || l == ltmmPlay_State_Paused) 
            g_pPlay->Run(); 
         else if(l == ltmmPlay_State_Running) 
            g_pPlay->Pause(); 
      }   
      return 0; 
      break; 
   } 
   return DefWindowProc(hwnd, message, wParam, lParam); 
} 
int APIENTRY WinMain(HINSTANCE hInstance, 
                     HINSTANCE hPrevInstance, 
                     LPSTR lpCmdLine, 
                     int nCmdShow) 
{ 
   MSG msg; 
   HRESULT hr; 
   WNDCLASSEX wcex; 
   g_hInstance = hInstance; 
    
   // initialize COM library 
   hr = CoInitialize(NULL); 
   if(FAILED(hr)) 
      goto error; 
 
   // register the video frame window class 
   wcex.cbSize = sizeof(WNDCLASSEX); 
   wcex.style = CS_HREDRAW | CS_VREDRAW; 
   wcex.lpfnWndProc = PlayWndProc; 
   wcex.cbClsExtra = 0; 
   wcex.cbWndExtra = 0; 
   wcex.hInstance = g_hInstance; 
   wcex.hIcon = NULL; 
   wcex.hCursor = LoadCursor(NULL, IDC_ARROW); 
   wcex.hbrBackground = (HBRUSH)(COLOR_APPWORKSPACE + 1); 
   wcex.lpszMenuName = (LPCWSTR)IDR_MENU; 
   wcex.lpszClassName = SZ_WNDCLASS_PLAY; 
   wcex.hIconSm = NULL; 
 
   if(!RegisterClassEx(&wcex)) 
      goto error; 
    
   // create the play object 
   hr = CoCreateInstance(CLSID_ltmmPlay, NULL, CLSCTX_INPROC_SERVER, IID_IltmmPlay, (void**) &g_pPlay); 
   if(FAILED(hr)) 
      goto error; 
    
   // create the video frame window 
   if(!CreateWindow(SZ_WNDCLASS_PLAY, _T("Play"), WS_OVERLAPPEDWINDOW | WS_CLIPCHILDREN, 
      CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, NULL, NULL, g_hInstance, NULL)) 
      goto error; 
    
   ShowWindow(g_hwndPlay, nCmdShow); 
   UpdateWindow(g_hwndPlay); 
   // process until done 
   while (GetMessage(&msg, NULL, 0, 0)) 
   {   
      TranslateMessage(&msg); 
      DispatchMessage(&msg); 
   } 
 
error: 
   if(g_pPlay) 
      g_pPlay->Release(); 
 
   CoUninitialize(); 
   return 0; 
}