// Read coordinates of video container window
RECT rc;
this->GetClientRect(&rc); //这里得到的矩形是对话框的,如果是把对话框作为播放窗口这样是对的,但是下面设置大小的时候就要改
long width = rc.right - rc.left;
long height = rc.bottom - rc.top - 50;
// Ignore the video's original size and stretch to fit bounding rectangle
hr = m_pVidWin->SetWindowPosition(rc.left, rc.top, width, height);
// hr = m_pVidWin->SetWindowPosition(0, 0, width, height); 这个是相对坐标
if(FAILED(hr))
{
AfxMessageBox(TEXT("m_pVidWin SetWindowPosition fail"));
return FALSE;
}