Adding metadata with images

Hi

How can I add more metadata with images with this plugin. I have modified “protected function make_image” in modules/uploads.php. But It doesn’t work. It still picking the default max-age. Added “cache Control”

$gcs_opts = [
   'gs' => [
	 'acl' => 'public-read',
	 'Cache-Control' => 'public, max-age=31536000',
   ],
		];

Please do reply asap!!
Thanks
Anshul

https://ww.wp.xz.cn/plugins/google-app-engine/