uses
 ComObj, ActiveX, PhotoShopTypeLibrary_TLB;
var
 PS: IPhotoShopApplication;
 Unknown: IUnknown;
begin
 Result := GetActiveObject(CLASS_PhotoshopApplication, nil, Unknown);
 if (Result = MK_E_UNAVAILABLE) then
  PS := CoPhotoshopApplication.Create
 else
 begin
  { make sure no other error occurred }
  OleCheck(Result);
  OleCheck(Unknown.QueryInterface(IPhotoShopApplication, PS));
 end;
 PS.Visible := True;
end;