{$DEFINE USE_THREADLOADING}
procedure TLoadImage.DoLoadImage(FileName : string);
var
    picRect : TRect;
    pWidth : integer;
    pHeight : integer;
    jp : TJPEGImage;
    pic : TPicture;
begin
    EnterCriticalSection(fCS);
    try
        if FileName = '' then exit;

        OutputDebugString(PChar('Loading image ' +FileName));
        fInLoad := TRUE;
        fLoadedImage := '';

        jp := TJPEGImage.Create;
        jp.LoadFromFile(FileName);
        pWidth := jp.Width;
        pHeight := jp.Height;

        if assigned(fBitmap) then fBitmap.Free;

        fBitmap := TBitmap.Create;
        fBitmap.Width := 1280;
        fBitmap.Height := 1024;
        fBitmap.PixelFormat := pf32bit;
        fBitmap.Canvas.Brush.Color := clBlack;
        Windows.FillRect(fBitmap.Canvas.Handle, Rect(0,0,fBitmap.Width, fBitmap.Height), fBitmap.Canvas.Brush.Handle);

        if (pWidth / pHeight) > (1280 / 1024) then begin
            picRect := Rect(0, (1024 - round((1280 / pWidth) * pHeight)) div 2, 1280, 0);
            picRect.Bottom := fBitmap.Height - picRect.Top;
        end
        else begin
            picRect := Rect(1280 - (round((1024 / pHeight) * pWidth)) div 2, 0, 0, 1024);
            picRect.Right := fBitmap.Width - picRect.Left;
        end;

        fBitmap.Canvas.StretchDraw(picRect, jp);

        fLoadedImage := FileName;
        fInLoad := FALSE;
        fFileName := '';

        OutputDebugString(PChar('Finish Loading image ' +fLoadedImage));
    finally
        jp.Free;
        LeaveCriticalSection(fCS);
    end;
end;

procedure TMainForm.LoadNextImage;
begin
{$IFDEF USE_THREADLOADING}
        if not TryEnterCriticalSection(imgLoader.fCS) then begin
            OutputDebugString('Bild noch nicht vollständig geladen Recheck in 100ms');
            trCheckLoadImage.Interval := 100;
            trCheckLoadImage.Enabled := TRUE;
            exit;
        end;
        try
            if imgLoader.LoadedImage = '' then begin
                OutputDebugString('No image loaded Recheck in 1000ms');
                trCheckLoadImage.Interval := 1000;
                trCheckLoadImage.Enabled := TRUE;
                imgLoader.LoadImage(PicturesPath + '\' + GetNextImageName(LoadedImage));
                exit;
            end;

            LoadedImage := ExtractFileName(imgLoader.LoadedImage);
            OutputDebugString(PChar('Image loaded : Using image : '+LoadedImage));
{$ELSE}
            imgLoader.DoLoadImage(PicturesPath + '\' + GetNextImageName(LoadedImage));
{$ENDIF}
            Picshow.Picture.Bitmap.Width := imgLoader.Bitmap.Width;
            Picshow.Picture.Bitmap.Height := imgLoader.Bitmap.Height;
            Picshow.Picture.Bitmap.PixelFormat := imgLoader.Bitmap.PixelFormat;
            BitBlt(PicShow.Picture.Bitmap.Canvas.Handle, 0, 0, Picshow.Picture.Bitmap.Width, Picshow.Picture.Bitmap.Height
                    , imgLoader.Bitmap.Canvas.Handle, 0, 0, SRCCOPY);

{$IFDEF USE_THREADLOADING}
            imgLoader.LoadImage(PicturesPath + '\' + GetNextImageName(LoadedImage));
        finally
            LeaveCriticalSection(imgLoader.fCS);

            trCheckLoadImage.Interval := 2000;
            trCheckLoadImage.Enabled := TRUE;
        end;
{$ENDIF}
end;