Set filenames as it's equivalent SHA256

renamefilestosha256.php

<?php

// usage: php renamefiles.php /path/to/dir
$photosDir = $_SERVER['argv']['1'];

$files = scandir($photosDir);
foreach ($files as $file) {
    if ($file == '.' || $file == '..') {
        continue;
    }
    $oldFile = "$photosDir$file";
    $extension = pathinfo($oldFile, PATHINFO_EXTENSION);
    $hash = hash_file('sha256', $oldFile);
    $newFile = "$photosDir$hash.$extension";
    rename($oldFile, $newFile);
}