紧急求救：DirectShow编程时编译出错

Tools->Options->Directories设置如下：
Directories:
C:\mssdk\include
C:\MSSDK\LIB
C:\MSSDK\SAMPLES
Project->Settings->Link设置如下：
在Object/library modules后面加：ddraw.lib dxguid.libPlay.cpp:
#include "ddraw.h" 
#include "mmstream.h" 
#include "amstream.h" 
#include "ddstream.h"
#include "stdafx.h"DDSURFACEDESC ddsd; 
IDirectDraw *pDD; 
IDirectDrawSurface *pPrimarySurface; 
IMultiMediaStream *pMMStream;
HWND hPlayWnd;HRESULT Init(); 
void Uninit();
HRESULT InitDDraw();
HRESULT LoadFromFile(const char * szFileName, IMultiMediaStream **ppMMStream, 
IDirectDraw *pDD);
HRESULT Play(IDirectDrawSurface *pSurface, IMultiMediaStream *pMMStream);Build:
Play.cpp
F:\linxiandong\PLAYVIDEO\Play.cpp(7) : error C2146: syntax error : missing ';' before identifier 'ddsd'
F:\linxiandong\PLAYVIDEO\Play.cpp(7) : error C2501: 'DDSURFACEDESC' : missing storage-class or type specifiers
F:\linxiandong\PLAYVIDEO\Play.cpp(7) : fatal error C1004: unexpected end of file found
Generating Code...
Error executing cl.exe.PLAYVIDEO.exe - 3 error(s), 0 warning(s)