PHP: Get file extension not working on uploads to S3

Question

I am using the Amazon S3 API to upload files and I am changing the name of the file each time I upload.

So for example:

Dog.png > 3Sf5f.png

Now I got

Answer 1

if you're uploading images try this

$dim = getimagesize($file);
$type = $dim[2];
if( $type == IMAGETYPE_JPEG ) $ext=".jpg"; 
if( $type == IMAGETYPE_GIF ) $ext=".gif"; 
if( $type == IMAGETYPE_PNG ) $ext=".png";

$params->key = rand_string(5).$ext;