裏面的坐標,應該用相對坐標,即相對於視頻控件的坐標
比如假設妳顯示視頻控件的ID為IDC_STATIC_IMG
CWnd *m_pWndCap = GetDlgItem(IDC_STATIC_IMG);
CRect rc;
m_pWndCap->GetWindowRect(&rc);
ScreenToClient(&rc);
int x1 = rc.CenterPoint().x-10;
int y1 = rc.CenterPoint().y-10;
int x2 = rc.CenterPoint().x+10;
int y2 = rc.CenterPoint().y+10;
這樣坐標就是相對於視頻控件的坐標了,要畫多大可以自己修改
然後調用 妳上面用的
DrawRectangle(m_hWnd, x1, y1, x2, y2);