The MCIWNDM_SETZOOM message resizes a video image according to a zoom factor. This marco adjusts the size of an MCIWnd window while maintaining a constant aspect ratio. You can send this message explicitly or by using the MCIWndSetZoom macro.
MCIWNDM_SETZOOM
wParam = 0;
lParam = (LPARAM) (UINT) iZoom;
This message does not return a value.
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Unsupported.
Header: Declared in vfw.h.
MCIWnd Window Class Overview, MCIWnd Messages, MCIWndSetZoom