which one is better for checking images? php or js - php

Question

I need to check images of contents on website.
I wrote code use php that doesn't have a problem, but I found some different ways on internet(Click to see example!)
from your opinion which is more efficient?
My website template seems like this: https://imgur.com/XOdDEZu
below is my php code :
$random_img = rand(1,9); // I have saved images to folder img_1, img_2 ...
$fixed_image = "<img src='public/img/duz/img_".$random_img.".jpg' style='width: 100%; height:320px; filter: blur(.1rem);' border:2px solid red;>";
$uploaded_img_file = "public/upload/$value->content_img";
$img_url = $value->content_img;
$find_letters = array('jpg', 'jpeg', 'png','gif','svg');
$match = (str_replace($find_letters, '', substr($img_url,-4)) != substr($img_url,-4));
//true if the last 4 characters of img url match the 4 characters in the array; returns false if it does not match
if (empty($value->content_img)) {
echo $fixed_img;
echo $a;
}elseif (file_exists($uploaded_img_file)) {
echo "<img src='".$uploaded_img_file."'>";
//print_r($uploaded_img_file);
}elseif (strlen($img_url)>=3) { //If the string length of the data from the database exceeds 3 characters. (no image if less than three characters)
if (filter_var($img_url, FILTER_VALIDATE_URL) !== false && $match==true) { //url validation check
echo "<img src='".$img_url."'>";
}else{
echo $fixed_img;
$String_title = $value->content_title;
$title_limit = limit_text($String_baslik, 10);
echo $a;
}
//print_r($img_url);
}else{
echo $fixed_img;
echo '<div style="position:absolute; left:15px; bottom:5px; text-decoration: none;"><span>Merhaba</span></div>';
}