看看下面代码的代码：

const WM_CAP_START = WM_USER;
const WM_CAP_STOP = WM_CAP_START + 68;
const WM_CAP_DRIVER_CONNECT = WM_CAP_START + 10;
const WM_CAP_DRIVER_DISCONNECT = WM_CAP_START + 11;
const WM_CAP_SAVEDIB = WM_CAP_START + 25;
const WM_CAP_GRAB_FRAME = WM_CAP_START + 60;
const WM_CAP_SEQUENCE = WM_CAP_START + 62;
const WM_CAP_FILE_SET_CAPTURE_FILEA = WM_CAP_START + 20;
const WM_CAP_SEQUENCE_NOFILE =WM_CAP_START+ 63
const WM_CAP_SET_OVERLAY =WM_CAP_START+ 51
const WM_CAP_SET_PREVIEW =WM_CAP_START+ 50
const WM_CAP_SET_CALLBACK_VIDEOSTREAM = WM_CAP_START +6;
const WM_CAP_SET_CALLBACK_ERROR=WM_CAP_START +2;
const WM_CAP_SET_CALLBACK_STATUSA= WM_CAP_START +3;
const WM_CAP_SET_CALLBACK_FRAME= WM_CAP_START +5;
const WM_CAP_SET_SCALE=WM_CAP_START+ 53
const WM_CAP_SET_PREVIEWRATE=WM_CAP_START+ 52

function capCreateCaptureWindowA(lpszWindowName : PCHAR; dwStyle : longint; x : integer;
y : integer;nWidth : integer;nHeight : integer;ParentWin : HWND;
nId : integer): HWND;STDCALL EXTERNAL AVICAP32.DLL;
　　上面的代码就是我们主要用到的一个函数和常量的定义。

　　好了，打开你的Delphi，新建一个工程，将上面的定义加上吧。

　　新建一个窗口，放个Panel上去，添加一个按钮，Caption设置为"开始"这里需要定义一个全局变量，var hWndC : THandle; 开始按钮代码如下：

begin
hWndC := capCreateCaptureWindowA(My Own Capture Window,WS_CHILD or WS_VISIBLE ,Panel1.Left,Panel1.Top,Panel1.Width,Panel1.Height,Form1.Handle,0);

hWndC := capCreateCaptureWindowA(My Own Capture Window,WS_CHILD or WS_VISIBLE ,Panel1.Left,Panel1.Top,Panel1.Width,Panel1.Height,Form1.Handle,0);
if hWndC <> 0 then
begin
SendMessage(hWndC, WM_CAP_SET_CALLBACK_VIDEOSTREAM, 0, 0);
SendMessage(hWndC, WM_CAP_SET_CALLBACK_ERROR, 0, 0);
SendMessage(hWndC, WM_CAP_SET_CALLBACK_STATUSA, 0, 0);
SendMessage(hWndC, WM_CAP_DRIVER_CONNECT, 0, 0);
SendMessage(hWndC, WM_CAP_SET_SCALE, 1, 0);
SendMessage(hWndC, WM_CAP_SET_PREVIEWRATE, 66, 0);
SendMessage(hWndC, WM_CAP_SET_OVERLAY, 1, 0);
SendMessage(hWndC, WM_CAP_SET_PREVIEW, 1, 0);
end;

　　按F9运行一下，怎么样，是不是可以看到摄像头的视屏了？那怎么停下来？再加个按钮caption设置成"停止" 。代码如下：

if hWndC <> 0 then begin
SendMessage(hWndC, WM_CAP_DRIVER_DISCONNECT, 0, 0);
hWndC := 0;
end;
　　视屏截到了，怎么把它给保存下来呢？下面按两种方式保存，一个是BMP静态图，一个是AVI动画。

　　再放三个按钮到窗体上去，caption分别设置成"保存BMP"、"开始录像"、"停止录像"，三个按钮的代码分别如下：

//保存BMP
if hWndC <> 0 then begin
SendMessage(hWndC,WM_CAP_SAVEDIB,0,longint(pchar(c:test.bmp)));
end;

//开始录像
if hWndC <> 0 then
begin
SendMessage(hWndC,WM_CAP_FILE_SET_CAPTURE_FILEA,0, Longint(pchar(c:test.avi)));
SendMessage(hWndC, WM_CAP_SEQUENCE, 0, 0);
end;

//停止录像
if hWndC <> 0 then begin
SendMessage(hWndC, WM_CAP_STOP, 0, 0);
end;

　　再运行看看吧。。可以保存几张图看看，也可以录成AVI以后慢慢欣赏。

　　程序运行效果：