저장은 되는데 읽기가 안됩니다.

읽기에서 'Bitmap Image is not Valid' 라는 에러가 납니다.
원인을 모르게어요

MSSQL에서 테이불은

열이름       데이터형식  길이
EmpCode varchar      10
Picture     image         16

간단히 이렇게 디자인되었습니다.

Delphi 7을 사용하고 있습니다.

////////////////////////////////////////////////////////////////////////////////////////////////
unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ExtCtrls, DB, ADODB, ExtDlgs, Jpeg, Grids, DBGrids,
  DBCtrls;

type
  TForm1 = class(TForm)
    ADOConnection1: TADOConnection;
    QQ: TADOQuery;
    Button1: TButton;
    OPD: TOpenPictureDialog;
    btnSave: TButton;
    btnRead: TButton;
    DataSource1: TDataSource;
    DBImage1: TDBImage;
    Panel1: TPanel;
    IMG: TImage;
    Panel2: TPanel;
    IMG1: TImage;
    procedure Button1Click(Sender: TObject);
    procedure btnSaveClick(Sender: TObject);
    procedure btnReadClick(Sender: TObject);
  private
  public
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}
//그림찾기
procedure TForm1.Button1Click(Sender: TObject);
begin
  if OPD.Execute then
    IMG.Picture.LoadFromFile(OPD.FileName);
end;
//저장
procedure TForm1.btnSaveClick(Sender: TObject);
var     BitImage  : TBitmap;
         JpegImage : TJPEGImage;
         MemStream : TMemoryStream;
begin
   QQ.Close;
   QQ.SQL.Clear;
   QQ.SQL.Add('INSERT INTO TMP_PICTURE (EmpCode, Picture )');
   QQ.SQL.Add('VALUES (''2000'', :Picture)');
   if IMG.Picture.Graphic is TBitmap then  begin
     BitImage   := TBitmap.Create;
     MemStream  := TMemoryStream.Create;

     MemStream.Position := 0;
     if IMG.Picture.Graphic = nil then   begin
       QQ.Parameters.ParamByName( 'PICTURE' ).Assign( IMG.Picture.Bitmap );
       end
     else begin
       BitImage.Assign( IMG.Picture.Bitmap );
       BitImage.SaveToStream( MemStream );
       QQ.Parameters.ParamByName( 'PICTURE' ).LoadFromStream( MemStream, ftBlob );
       end;
     QQ.ExecSQL;
     BitImage.Destroy;
     MemStream.Destroy;
     end else
   if IMG.Picture.Graphic is TJPEGImage then begin
     JpegImage   := TJPEGImage.Create;
     MemStream  := TMemoryStream.Create;
     MemStream.Position := 0;
     if IMG.Picture.Graphic = nil then  begin
       QQ.Parameters.ParamByName( 'PICTURE' ).Assign( IMG.Picture.Bitmap );
       end
    else  begin
       JPEGImage.Assign( IMG.Picture.Graphic );
       JPEGImage.SaveToStream( MemStream );
       QQ.Parameters.ParamByName( 'PICTURE' ).LoadFromStream( MemStream, ftBlob );
       end;
    QQ.ExecSQL;
    JPEGImage.Destroy;
    MemStream.Destroy;
    end;
end;

//읽기
procedure TForm1.btnReadClick(Sender: TObject);
begin
  QQ.Close;
  QQ.SQL.Clear;
  QQ.SQL.Add('select PICTURE from TMP_PICTURE');
  QQ.SQL.Add('where EMpCode = ''2000''');
  QQ.Open;
  if QQ.FieldByName('PICTURE').IsBlob then
     IMG1.Picture.Assign(QQ.FieldByName('PICTURE'));  //여기서 에러 'Bitmap Image is not Valid'
end;
///////////////////////////////////////////////////////////////////////////////////////////////////////////

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