Recompressing an MP4 File Example for C++

//The following code demonstrates how to recompress an MP4 file: // 
#define MAKE_MEDIA_PATH(pFileName) (TEXT("C:\\LEADTOOLS Media Foundation\\Media\\")TEXT(pFileName)) 
// include the LEAD Multimedia TOOLKIT header 
#include "ltmf.h" 
#include "resource.h" 
#include <tchar.h> 
#include <stdio.h> 
#include <assert.h> 
HINSTANCE g_hInstance; // application instance handle 
IltmfConvert* g_pConvert; // convert object's interface pointer 
// user defined message id used for conversion events 
#define WM_CONVERTNOTIFY (WM_USER + 1000) 
// 
// ConvertDlgProc 
// starts the conversion process and provides status feedback 
// 
// controls: 
// IDC_CONVERTSTATUS - static control used for status messages 
// IDC_CONVERTPROGRESS - static control used for conversion progress 
// IDC_USERABORT - button control used to abort the conversion or exit the dialog 
BOOL CALLBACK ConvertDlgProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) 
{ 
   TCHAR sz[256]; 
   BSTR bstr1; 
   HRESULT hr; 
   long streams; 
   switch (msg) 
   { 
   case WM_INITDIALOG: 
      // assign the notification window 
      g_pConvert->SetNotifyWindow((long) hwnd, WM_CONVERTNOTIFY); 
      // set the abort button text 
      SetDlgItemText(hwnd, IDC_USERABORT, _T("Abort")); 
      // start the conversion 
      hr = g_pConvert->StartConvert(); 
      if(FAILED(hr)) 
      { 
         bstr1 = ltmfGetErrorText(hr); 
         _stprintf(sz, _T("%ls"), bstr1); 
         SysFreeString(bstr1); 
         UpdateWindow(GetDlgItem(hwnd, IDC_CONVERTSTATUS)); 
         SetDlgItemText(hwnd, IDC_USERABORT, _T("Exit")); 
         MessageBeep(0); 
      } 
      g_pConvert->get_UnrenderedStreams(&streams); 
      if(streams != 0) 
         MessageBox(hwnd, _T("Not all the streams could be rendered."), _T("Convert"), MB_ICONEXCLAMATION | MB_OK); 
      return TRUE; 
      break; 
   case WM_DESTROY: 
      // reset the notification window 
      g_pConvert->SetNotifyWindow((long) NULL, 0); 
#ifdef _DEBUG 
      { 
         long state, err, pc; 
         double start, end, dur; 
         TCHAR sz[1024]; 
         // get the current state 
         g_pConvert->get_State(&state); 
         // get the current state 
         g_pConvert->get_ConvertError(&err); 
         // get the amount converted 
         g_pConvert->get_PercentComplete(&pc); 
         // get the start 
         g_pConvert->get_SelectionStart(&start); 
         // get the end 
         g_pConvert->get_SelectionEnd(&end); 
         // get the duration 
         g_pConvert->get_Duration(&dur); 
         _stprintf(sz, _T("state = %d, error = 0x%.8X, complete = %d complete"), lParam); 
         SetDlgItemText(hwnd, IDC_CONVERTPROGRESS, sz); 
         UpdateWindow(GetDlgItem(hwnd, IDC_CONVERTPROGRESS)); 
         break; 
      } 
#endif 
      return TRUE; 
      break; 
   } 
   return FALSE; 
} 
// 
// SetAudioType 
// Set the audio type into the target format if: 
// 
void SetAudioType(IltmfTargetFormat* pTargetFormat) 
{ 
   // get target audio formats 
   IltmfTargetAudioFormats* pTargetAudioFormats; 
   pTargetFormat->get_AudioFormats(&pTargetAudioFormats); 
   long v = -1; 
   pTargetAudioFormats->get_Selection(&v); 
   if (v < 0) 
   { 
      pTargetAudioFormats->Release(); 
      return; 
   } 
   IltmfTargetAudioFormat* pTargetAudioFormat; 
   pTargetAudioFormats->Item(v, &pTargetAudioFormat); 
   pTargetAudioFormats->Release(); 
   // get target audio types collection 
   IltmfTargetAudioTypes* pTargetAudioTypes; 
   pTargetAudioFormat->get_AudioTypes(&pTargetAudioTypes); 
   pTargetAudioFormat->Release(); 
   long lCount = 0; 
   pTargetAudioTypes->get_Count(&lCount); 
   for ( long lIndex = 0 ; lIndex < lCount ; lIndex++) 
   { 
      // get target audio type of index 
      IltmfTargetAudioType* pTargetAudioType; 
      pTargetAudioTypes->Item(lIndex, &pTargetAudioType); 
      long nAvgBytesPerSecond; 
      long nBitsPerSample; 
      long nNumChannels; 
      long nSamplesPerSecond; 
      pTargetAudioType->get_AudioAvgBytesPerSecond(&nAvgBytesPerSecond); 
      pTargetAudioType->get_AudioBitsPerSample(&nBitsPerSample); 
      pTargetAudioType->get_AudioNumChannels(&nNumChannels); 
      pTargetAudioType->get_AudioSamplesPerSecond(&nSamplesPerSecond); 
      // set the audio type into the target format if: 
      // AudioAvgBytesPerSecond == 24000 (192 kbps) 
      // AudioBitsPerSample == 16 
      // AudioNumChannels == 2 (stereo) 
      // AudioSamplesPerSecond == 44100 Hz 
      if (nAvgBytesPerSecond == 24000 && 
         nBitsPerSample == 16 && 
      nNumChannels == 2 && 
      nSamplesPerSecond == 44100 ) 
      { 
         pTargetFormat->SetAudioType(pTargetAudioType); 
         pTargetAudioType->Release(); 
         break; 
      } 
      pTargetAudioType->Release(); 
   } 
   pTargetAudioTypes->Release(); 
} 
// 
// SetMP4Recompression 
// sets up H264 target video format, AAC target audio format, and MP4 file output 
// 
// hwndParent = parent window for target format property dialog boxes 
// 
HRESULT SetMP4Recompression(HWND hwndParent) 
{ 
   long index; 
   VARIANT_BOOL f; 
   BSTR bstr; 
   // set output format to MP4 
   g_pConvert->put_TargetFormat(ltmfConvert_TargetFormat_MP4); 
#ifdef _DEBUG 
   { 
      long v; 
      g_pConvert->get_TargetFormat(&v); 
      assert(v == ltmfConvert_TargetFormat_MP4); 
   } 
#endif 
   // get target format 
   IltmfTargetFormats* pTargetFormats; 
   IltmfTargetFormat*  pTargetFormat; 
   g_pConvert->get_TargetFormats(&pTargetFormats); 
   long v; 
   pTargetFormats->get_Selection(&v); 
   pTargetFormats->Item(v, &pTargetFormat); 
   pTargetFormats->Release(); 
   // get target video formats 
   IltmfTargetVideoFormats* pTargetVideoFormats; 
   pTargetFormat->get_VideoFormats(&pTargetVideoFormats); 
   // select the H264 target video format 
   bstr = SysAllocString(L"{34363248-0000-0010-8000-00AA00389B71}"); 
   pTargetVideoFormats->Find(bstr, &index); 
   SysFreeString(bstr); 
   if(index < 0) 
   { 
      // video target format isn't registered 
      pTargetFormat->Release(); 
      pTargetVideoFormats->Release(); 
      return E_FAIL; 
   } 
   pTargetVideoFormats->put_Selection(index); 
   pTargetVideoFormats->Release(); 
   // set Video bit rate to 500 KB 
   pTargetFormat->put_VideoBitrate(500000); 
   // set Video EncodeQuality to 10 
   pTargetFormat->put_VideoEncodeQuality(10); 
   // set Video Frame Width to 320 
   pTargetFormat->put_VideoFrameWidth(320); 
   // set Video Frame Height to 240 
   pTargetFormat->put_VideoFrameHeight(240); 
   // set Video Frame Rate to 30.0 fps 
   pTargetFormat->put_VideoFrameRate(30.0); 
#ifdef _DEBUG 
   { 
      long v; 
      pTargetFormat->get_VideoBitrate(&v); 
      assert(v == 500000); 
      pTargetFormat->get_VideoEncodeQuality(&v); 
      assert(v == 10); 
      pTargetFormat->get_VideoFrameWidth(&v); 
      assert(v == 320); 
      pTargetFormat->get_VideoFrameHeight(&v); 
      assert(v == 240); 
      double d; 
      pTargetFormat->get_VideoFrameRate(&d); 
      assert(d == 30.0); 
   } 
#endif 
   // get target audio formats 
   IltmfTargetAudioFormats* pTargetAudioFormats; 
   pTargetFormat->get_AudioFormats(&pTargetAudioFormats); 
   // select the AAC target audio format 
   bstr = SysAllocString(L"{00001610-0000-0010-8000-00AA00389B71}"); 
   pTargetAudioFormats->Find(bstr, &index); 
   SysFreeString(bstr); 
   if(index < 0) 
   { 
      // audio target format isn't registered 
      pTargetFormat->Release(); 
      pTargetAudioFormats->Release(); 
      return E_FAIL; 
   } 
   pTargetAudioFormats->put_Selection(index); 
   pTargetAudioFormats->Release(); 
   // set Audio Avg Bytes Per Second to 12000 (96 Kbps) 
   pTargetFormat->put_AudioAvgBytesPerSecond(12000) ; 
   // set Audio Bits Per Sample to 16 
   pTargetFormat->put_AudioBitsPerSample(16); 
   // set Audio Channels number to 2 (stereo) 
   pTargetFormat->put_AudioNumChannels(2); 
   // set Audio samples per second to 44100 (44.1 KHz) 
   pTargetFormat->put_AudioSamplesPerSecond(44100); 
#ifdef _DEBUG 
   { 
      long v; 
      pTargetFormat->get_AudioAvgBytesPerSecond(&v); 
      assert(v == 12000); 
      pTargetFormat->get_AudioBitsPerSample(&v); 
      assert(v == 16); 
      pTargetFormat->get_AudioNumChannels(&v); 
      assert(v == 2); 
      pTargetFormat->get_AudioSamplesPerSecond(&v); 
      assert(v == 44100); 
   } 
#endif 
   pTargetFormat->Release(); 
   // set target format properties 
   g_pConvert->HasDialog(ltmfConvert_Dlg_TargetFormat, &f); 
   if(f) 
      g_pConvert->ShowDialog(ltmfConvert_Dlg_TargetFormat, (long) hwndParent); 
   return S_OK; 
} 
// 
// RecompressFile 
// recompresses a file using the MP4 target format 
// 
// pszSource = source file path 
// pszTarget = target file path 
// 
HRESULT RecompressFile(LPCTSTR pszSource, LPCTSTR pszTarget) 
{ 
   HRESULT hr; 
   BSTR bstr; 
#ifndef _UNICODE 
   WCHAR wsz[MAX_PATH]; 
#endif 
   // set source file 
#ifdef _UNICODE 
   bstr = SysAllocString(pszSource); 
#else 
   swprintf(wsz, L"%hs", pszSource); 
   bstr = SysAllocString(wsz); 
#endif 
   hr = g_pConvert->put_SourceFile(bstr); 
   SysFreeString(bstr); 
   if(FAILED(hr)) 
      return hr; 
   // set target file 
#ifdef _UNICODE 
   bstr = SysAllocString(pszTarget); 
#else 
   swprintf(wsz, L"%hs", pszTarget); 
   bstr = SysAllocString(wsz); 
#endif 
   hr = g_pConvert->put_TargetFile(bstr); 
   SysFreeString(bstr); 
   if(FAILED(hr)) 
      return hr; 
   // setup AVI recompression 
   hr = SetMP4Recompression(NULL); 
   if(FAILED(hr)) 
      return hr; 
   // do conversion 
   hr = (HRESULT) DialogBox(g_hInstance, (LPCTSTR)IDD_CONVERTDLG, NULL, ConvertDlgProc); 
   return hr; 
} 
int APIENTRY WinMain(HINSTANCE hInstance, 
HINSTANCE hPrevInstance, 
LPSTR      lpCmdLine, 
int      nCmdShow) 
{ 
   HRESULT hr; 
   g_hInstance = hInstance; 
   // initialize COM library 
   hr = CoInitialize(NULL); 
   if(FAILED(hr)) 
      goto error; 
   // create the convert object 
   hr = CoCreateInstance(CLSID_ltmfConvert, NULL, CLSCTX_INPROC_SERVER, IID_IltmfConvert, (void**) &g_pConvert); 
   if(FAILED(hr)) 
      goto error; 
   hr = RecompressFile(MAKE_MEDIA_PATH("source.MP4"), MAKE_MEDIA_PATH("target.MP4")); 
   if(FAILED(hr)) 
      goto error; 
error: 
   // cleanup 
   if(g_pConvert) 
      g_pConvert->Release(); 
   CoUninitialize(); 
   return 0; 
}