Jpeg файл - достать дату съемки (exif)

function getdaten(filename:string):string;
  function DateTimeToStr(const DateTime: TDateTime): string;
  begin
    if DateTime = 0 then
      Result := '<missing>'
    else
      Result := SysUtils.DateTimeToStr(DateTime);
  end;
var
  S: string;
  Data: TExifDataPatcher;
  Item: TListItem;
  ForceReadOnly: TModalResult;
  ForceReadOnlyOptions: TMsgDlgButtons;
  ReadOnly: Boolean;
begin
  S := filename;
  Data := nil; //prevent compiler warning
  ForceReadOnly := mrNone;
  ForceReadOnlyOptions := [mbYes, mbNo];
  begin
    ReadOnly := FileIsReadOnly(S);
    if ReadOnly then //we can't open a read-only file with read/write access obviously
    begin
      if ForceReadOnly = mrNone then
      begin
        ForceReadOnly := MessageDlg(Format(SReadOnlyFileMsg, [ExtractFileName(S)]),
          mtConfirmation, ForceReadOnlyOptions, 0, mbNo);
        if ForceReadOnly = mrNone then ForceReadOnly := mrNo;
      end;
      //if IsNegativeResult(ForceReadOnly) then
        //Continue;
      if not FileSetReadOnly(S, False) then
      begin
        MessageDlg(SysErrorMessage(GetLastError), mtError, [mbOK], 0);
        //Continue;
      end;
    end;
    try
      Data := TExifDataPatcher.Create(S);
    except
      on E: EInvalidJPEGHeader do     //If it's just that a certain file isn't a JPEG or
      begin                           //is corrupt, we still want to continue with any
        Application.ShowException(E); //other filenames we have been requested to process.
        //Continue;
      end
      else
        raise;
    end;
  
    result := DateTimeToStr(Data.DateTime);
  end;
end;