Question

How can I check for height and width before uploading image, using PHP.

Must I upload the image first and use “getimagesize()”? Or can I check this before uploading it using PHP?

<?php

foreach ($_FILES["files"]["error"] as $key => $error) {
if(
$error == UPLOAD_ERR_OK
&& $_FILES["files"]["size"][$key] < 500000 
&& $_FILES["files"]["type"][$key] == "image/gif"
|| $_FILES["files"]["type"][$key] == "image/png"
|| $_FILES["files"]["type"][$key] == "image/jpeg"
|| $_FILES["files"]["type"][$key] == "image/pjpeg" 
){


$filename = $_FILES["files"]["name"][$key];








if(HOW TO CHECK WIDTH AND HEIGHT)
{
echo '<p>image dimenssions must be less than 1000px width and 1000px height';
}


}







?>

Answer 1

You need something that is executed on the client before the actual upload happens.
With (server-side) php you can check the dimension only after the file has been uploaded or with upload hooks maybe while the image is uploaded (from the image file header data).

So your options are flash, maybe html5 with its FileAPI (haven’t tested that, maybe that’s not doable), java-applet, silverlight, …