Recompressing an AVI File for C++

The following code demonstrates how to recompress an AVI file:

#define MAKE_MEDIA_PATH(pFileName) (TEXT("C:\\LEADTOOLS 18\\Media\\")TEXT(pFileName))


// include the LEAD Multimedia TOOLKIT header
#include "ltmm.h"

#include "resource.h"
#include <tchar.h>
#include <stdio.h>
#include <assert.h>

HINSTANCE g_hInstance; // application instance handle
IltmmConvert* 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;
   BSTR bstr2;
   HRESULT hr;
   long state;
   long type;
   long streams;
   IltmmVCRControl* pVCR;


   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"));

   
      // uncomment the following line to view the the graph in DirectShow GraphEdit
      // g_pConvert->EditGraph();

      g_pConvert->get_UnrenderedStreams(&streams);
      if(streams != 0)
         MessageBox(hwnd, _T("Not all the streams could be rendered."), _T("Convert"), MB_ICONEXCLAMATION | MB_OK);

      g_pConvert->get_TargetVCRControl(&pVCR);
      hr = pVCR->Record();
      pVCR->Release();

      if(SUCCEEDED(hr))
         Sleep(2000);

      // start the conversion
      hr = g_pConvert->StartConvert();
      if(FAILED(hr))
      {
          bstr1 = ltmmGetErrorText(hr);
         _stprintf(sz, _T("%ls"), bstr1);
         SysFreeString(bstr1);
         UpdateWindow(GetDlgItem(hwnd, IDC_CONVERTSTATUS));
         SetDlgItemText(hwnd, IDC_USERABORT, _T("Exit"));
         MessageBeep(0);

         // stop, if vcr
         g_pConvert->get_TargetVCRControl(&pVCR);
         pVCR->Stop();
         pVCR->Release();

      }
      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;
      }
      return TRUE;
      break;
   }
   return FALSE;
}


//
// SetAVIRecompression
// sets up LEAD video compression, MP3 audio compression, and AVI file output
//
// hwndParent = parent window for compressor property dialog boxes
//
HRESULT SetAVIRecompression(HWND hwndParent)
{
   IltmmCompressors* pCompressors;
   long index;
   VARIANT_BOOL f;
   BSTR bstr;

   // select the LEAD video compressor
   g_pConvert->get_VideoCompressors(&pCompressors);
   bstr = SysAllocString(L"@device:sw:{33D9A760-90C8-11D0-BD43-00A0C911CE86}\\LEAD MCMP/MJPEG Codec (2.0)");

   pCompressors->Find(bstr, &index);
   SysFreeString(bstr);
   if(index < 0)
   {
      // compressor isn't registered
      pCompressors->Release();
      return E_FAIL;
   }
   pCompressors->put_Selection(index);
   pCompressors->Release();
   
   
   // select the MP3 audio video compressor
   g_pConvert->get_AudioCompressors(&pCompressors);
   bstr = SysAllocString(L"@device:cm:{33D9A761-90C8-11D0-BD43-00A0C911CE86}\\85MPEG Layer-3");
   pCompressors->Find(bstr, &index);
   SysFreeString(bstr);

   if(index < 0)
   {
      // compressor isn't registered
      pCompressors->Release();
      return E_FAIL;
   }
   pCompressors->put_Selection(index);
   pCompressors->Release();

   // set output format to AVI
   g_pConvert->put_TargetFormat(ltmmConvert_TargetFormat_Avi);
#ifdef _DEBUG
   {
      long v;
      g_pConvert->get_TargetFormat(&v);
      assert(v == ltmmConvert_TargetFormat_Avi);
   }
#endif

   // set preferred renderer
   g_pConvert->put_PreferredVideoRenderer(ltmmVideoRenderer_VMR9);

   // set video compressor properties
   g_pConvert->HasDialog(ltmmConvert_Dlg_VideoCompressor, &f);
   if(f)
      g_pConvert->ShowDialog(ltmmConvert_Dlg_VideoCompressor, (long) hwndParent);
   
   // set audio compressor properties
   g_pConvert->HasDialog(ltmmConvert_Dlg_AudioCompressor, &f);
   if(f)
      g_pConvert->ShowDialog(ltmmConvert_Dlg_AudioCompressor, (long) hwndParent);

   return S_OK;
}


//
// RecompressFile
// recompresses a file using the LEAD video and MP3 audio compressors
//
// 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 = SetAVIRecompression(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_ltmmConvert, NULL, CLSCTX_INPROC_SERVER, IID_IltmmConvert, (void**) &g_pConvert);
   if(FAILED(hr))
      goto error;
   
   
   hr = RecompressFile(MAKE_MEDIA_PATH("source.avi"), MAKE_MEDIA_PATH("target1.avi"));
   if(FAILED(hr))
      goto error;


error:
   // cleanup

   if(g_pConvert)
      g_pConvert->Release();

   CoUninitialize();
   
   return 0;
}