Using AutoSize with ltmfCapture Example for C++

The following example demonstrates automatically sizing the ltmfCapture object's video frame window to the actual size of the media.

// include the LEAD Media Foundation TOOLKIT header
#include "ltmf.h"
#include "resource.h"
#include <tchar.h>
#include <stdio.h>
#include <assert.h>
#define SZ_WNDCLASS_CAPTURE _T("CAPTURE WNDCLASS")
#define WM_CAPTURENOTIFY (WM_USER + 1000)
HINSTANCE g_hInstance;  // application instance handle
HWND g_hwndCapture;  // video frame window
IltmfCapture* g_pCapture;  // capture object interface pointer
//
// CaptureWndProc
// video frame window procedure
//
LRESULT CALLBACK CaptureWndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
   IltmfDevices* pDevices;
   switch (message)
   {
   case WM_CREATE:
      g_hwndCapture = hwnd;
      // window is the video window frame
      g_pCapture->put_VideoWindowFrame((long) hwnd);
      // force the frame window to be automatically resized to the video
      g_pCapture->put_AutoSize(VARIANT_TRUE);
#ifdef _DEBUG
      {
         VARIANT_BOOL f;
         g_pCapture->get_AutoSize(&f);
         assert(f != 0);
      }
#endif
      // set preview source video only
      g_pCapture->put_PreviewSource(ltmfCapture_Preview_Video);
      // enable preview
      g_pCapture->put_Preview(VARIANT_TRUE);
      // select the first video device available
      g_pCapture->get_VideoDevices(&pDevices);
      pDevices->put_Selection(0);
      pDevices->Release();
      return 0;
      break;
   case WM_DESTROY:
      PostQuitMessage(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 = CaptureWndProc;
   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 = NULL;
   wcex.lpszClassName = SZ_WNDCLASS_CAPTURE;
   wcex.hIconSm = NULL;
   if(!RegisterClassEx(&wcex))
      goto error;
   // create the capture object
   hr = CoCreateInstance(CLSID_ltmfCapture, NULL, CLSCTX_INPROC_SERVER, IID_IltmfCapture, (void**) &g_pCapture);
   if(FAILED(hr))
      goto error;
   // create the video frame window
   if(!CreateWindow(SZ_WNDCLASS_CAPTURE, _T("Capture"), WS_OVERLAPPEDWINDOW | WS_CLIPCHILDREN,
      CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, NULL, NULL, g_hInstance, NULL))
      goto error;
   ShowWindow(g_hwndCapture, nCmdShow);
   UpdateWindow(g_hwndCapture);
   // process until done
   while (GetMessage(&msg, NULL, 0, 0))
   {
      TranslateMessage(&msg);
      DispatchMessage(&msg);
   }
error:
   if(g_pCapture)
      g_pCapture->Release();
   CoUninitialize();
   return 0;
}