Как получить картинку с видео источника

unit
 Unit1;

interface


uses

  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms,
  Dialogs, ExtCtrls, StdCtrls;

type

  TForm1 = class
(TForm)
    Panel1: TPanel;
    OpenVideo: TButton;
    CloseVideo: TButton;
    GrabFrame: TButton;
    SaveBMP: TButton;
    StartAVI: TButton;
    StopAVI: TButton;
    SaveDialog1: TSaveDialog;
    procedure
 FormCreate(Sender: TObject);
    procedure
 OpenVideoClick(Sender: TObject);
    procedure
 CloseVideoClick(Sender: TObject);
    procedure
 GrabFrameClick(Sender: TObject);
    procedure
 SaveBMPClick(Sender: TObject);
    procedure
 StartAVIClick(Sender: TObject);
    procedure
 StopAVIClick(Sender: TObject);
  private

    { Private declarations }
    hWndC: THandle;
    CapturingAVI: bool;
  public

    { Public declarations }
  end
;

var

  Form1: TForm1;

implementation


{$R *.DFM}

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;

function
 capCreateCaptureWindowA(lpszWindowName: PCHAR;
  dwStyle: longint;
  x: integer;
  y: integer;
  nWidth: integer;
  nHeight: integer;
  ParentWin: HWND;
  nId: integer): HWND;
  stdcall
 external
 'AVICAP32.DLL';

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

    SendMessage(hWndC, WM_CAP_DRIVER_CONNECT, 0, 0);
end
;

procedure
 TForm1.CloseVideoClick(Sender: TObject);
begin

  if
 hWndC <> 0 then

  begin

    SendMessage(hWndC, WM_CAP_DRIVER_DISCONNECT, 0, 0);
    hWndC := 0;
  end
;
end
;

procedure
 TForm1.GrabFrameClick(Sender: TObject);
begin

  if
 hWndC <> 0 then

    SendMessage(hWndC, WM_CAP_GRAB_FRAME, 0, 0);
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

  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
;

end
.