First of all, according to our conversation below, change back the PATH to use http://, after it use this code for downloading images to a compressed folder.
$zip = new ZipArchive();
$tmp_file = tempnam('.','');
$zip->open($tmp_file, ZipArchive::CREATE);
foreach($files as $file){
$download_file = file_get_contents($file);
$zip->addFromString(basename($file),$download_file);
$zip->close();
header('Content-disposition: attachment; filename=download.zip');
header('Content-type: application/zip');
readfile($tmp_file);
Hope that helps,