unit main;

interface

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

type
  TForm1 = class(TForm)
    Button1: TButton;
    Image1: TImage;
    BitBtn1: TBitBtn;
    BitBtn2: TBitBtn;
    Image2: TImage;
    procedure FormCreate(Sender: TObject);
    procedure Button1Click(Sender: TObject);
    procedure BitBtn1Click(Sender: TObject);
    procedure BitBtn2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
    hdib, testdib: hbitmap;
    w, h: integer;
    n: Integer;
  end;

var
  Form1: TForm1;

procedure CallbackFxn(CurDib: THandle; index: Integer); stdcall; forward;

implementation

{$R *.DFM}

procedure TForm1.FormCreate(Sender: TObject);

begin
   hDib := 0;
   w := 0; h := 0;
   testDib := 0;
   TWAIN_RegisterCallback(CallbackFxn);
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
   TWAIN_SelectImageSource(0);
   hdib := TWAIN_AcquireNative(0, 0);
   n := TWAIN_GetNumDibs;
   if n >= 1 then
      begin
         TestDib := TWAIN_GetDib(0);
         CopyDibIntoImage(TestDib, Image1);
         TWAIN_FreeNative(TestDib);
         TestDib := 0;
      end;
   if n = 2 then
      begin
         TestDib := TWAIN_GetDib(1);
         CopyDibIntoImage(TestDib, Image2);
         TWAIN_FreeNative(TestDib);
         TestDib := 0;
      end;

end;

procedure TForm1.BitBtn1Click(Sender: TObject);
begin
   Image1.Visible := False;
   image1.Top := 0;
   Image1.Left := 0;
   Image1.Width := ClientWidth;
   Image1.Height := ClientHeight;
   Image1.Visible := True;
end;

procedure TForm1.BitBtn2Click(Sender: TObject);
begin
   Image1.Visible := False;
   image1.Top := 100;
   Image1.Left := 50;
   Image1.Width := 150;
   Image1.Height := 150;
   Image1.Visible := True;
end;

procedure CallbackFxn(CurDib: THandle; index: Integer); stdcall;
begin
   MessageBox(0, 'Called back!', 'CallbackFxn', mb_ok);
end;
end.