刘麻子大哥：
咱们不说这个 控件问题了 你说的那个方法 我 试了 可选中了以后，当新打开一个工程或新建一个时就又没了；
我现在关键问题在视频的捕捉和存储上，能否给个建议，或学习的方法。我有一段程序，可我看不懂，大家页帮忙看看，看了给我解释一下也可。 有劳大家了，小弟刚来，得大家照顾 嘿嘿
下面是那个源码，其中的一些注释是我加的，不知是否正确。大家看看
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, ExtCtrls;
type
TForm1 = class(TForm)
Panel1: TPanel;
SaveDialog1: TSaveDialog;
Panel2: TPanel;
OpenVideo: TButton;
CloseVideo: TButton;
SaveBMP: TButton;
StartAVI: TButton;
StopAVI: TButton;
procedure FormCreate(Sender: TObject);
procedure OpenVideoClick(Sender: TObject);
procedure CloseVideoClick(Sender: TObject);
procedure SaveBMPClick(Sender: TObject);
procedure StartAVIClick(Sender: TObject);
procedure StopAVIClick(Sender: TObject);
procedure FormClose(Sender: TObject; var Action: TCloseAction);
private
hWndC : THandle; //线程类 SendMessage 发送消息
CapturingAVI : bool;
{ Private declarations }
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
const WM_CAP_START = WM_USER;
{ 消息标识是整型大小的常量。Windows保存了小于1024的消息用于自己使用,因此当声明自己的消息时,你应当大于1024。
常量 WM_USER 代表用于自定义消息的开始数字。当定义消息标准时,你应当基于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; //Panel1.Left,
y : integer; //Panel1.Top,
nWidth : integer; //Panel1.Width,
nHeight : integer; //Panel1.Height,
ParentWin : HWND; //Form1.Handle,
nId : integer): HWND; //Provides access to the Window handle for the Web browser.
STDCALL EXTERNAL 'AVICAP32.DLL';
//●AVICAP.DLL:包含执行视频捕获的函数,它给AVI文件的I/O处理和视频、音频设备驱动程序提供一个高级接口;
procedure TForm1.FormCreate(Sender: TObject);
begin
CapturingAVI := false;
hWndC := 0;
SaveDialog1.Options :=
[ofHideReadOnly, ofNoChangeDir, ofPathMustExist]
end;
procedure TForm1.OpenVideoClick(Sender: TObject);
begin
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
// 其中hWndc 为目的窗口的句柄 两个参数传给前面的参数
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);
// 连接到捕获驱动 将MSVIDEO驱动连接到句柄为hWndC的捕获窗口, 然后调用capDriverDisconnect宏来断接.
SendMessage(hWndC, WM_CAP_SET_SCALE, 1, 0);
//WM_CAP_SET_SCALE(capPreviewScale宏)允许或禁止preview视频的缩放比例
SendMessage(hWndC, WM_CAP_SET_PREVIEWRATE, 66, 0);
//WM_CAP_SET_PREVIEWRATE(capPreviewRate宏)当帧在preview模式显示时设置速度.
SendMessage(hWndC, WM_CAP_SEQUENCE_NOFILE, 1, 0);
SendMessage(hWndC, WM_CAP_SET_OVERLAY, 1, 0);
//你可以发送消息WM_CAP_SET_OVERLAY 给捕获窗口来启用或终止overlay模式, 允许overlay模式会自动禁止preview模式.
SendMessage(hWndC, WM_CAP_SET_PREVIEW, 1, 0);
OpenVideo.Enabled :=false;
end;
procedure TForm1.CloseVideoClick(Sender: TObject);
begin
if hWndC <> 0 then begin
SendMessage(hWndC, WM_CAP_DRIVER_DISCONNECT, 0, 0);
hWndC := 0;
OpenVideo.Enabled :=true;
end;
end;
procedure TForm1.SaveBMPClick(Sender: TObject);
begin
if hWndC <> 0 then begin
SaveDialog1.DefaultExt := 'bmp';
SaveDialog1.Filter := 'Bitmap files (*.bmp)|*.bmp';
if SaveDialog1.Execute then
SendMessage(hWndC,
WM_CAP_SAVEDIB,
0,
longint(pchar(SaveDialog1.FileName)));
end;
end;
procedure TForm1.StartAVIClick(Sender: TObject); //begin save Btn
begin
if hWndC <> 0 then begin
SaveDialog1.DefaultExt := 'avi';
SaveDialog1.Filter := 'AVI files (*.avi)|*.avi';
if SaveDialog1.Execute then begin
CapturingAVI := true;
SendMessage(hWndC,
WM_CAP_FILE_SET_CAPTURE_FILEA,
0,
Longint(pchar(SaveDialog1.FileName)));
SendMessage(hWndC, WM_CAP_SEQUENCE, 0, 0);
end;
end;
end;
procedure TForm1.StopAVIClick(Sender: TObject);
begin
if hWndC <> 0 then begin
SendMessage(hWndC, WM_CAP_STOP, 0, 0);
CapturingAVI := false;
end;
end;
procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
CloseVideoClick(Sender);
end;
end.
]