How to read the firsts bytes of png,jpg and jpeg and get the height/width

Originally Posted by Salathe Then why were you looking for a faster way of getting the dimensions?

Im using regex with preg_match_all() to get all of the imgs tags on the passed url, my problem is that i want to validate the height and width. so it takes a lot of seconds to download only one image, so if there is a 30 imgs or something and all of them is 3megabyte or something. then it will take a looooot of time to read them, so i thought there would be a better way to get images height/width.

Thats why.

Thanks salathe :-)