Sniff for getimagesize()

[davidsword]

What problem would the enhancement address for VIP?

getimagesize() holds up the PHP process downloading the entire image to just read its file size.

Describe the solution you'd like

Most images in WPs Media Library have width and height attributes already (like from wp_get_attachment_metadata()) & that existing data should be used instead.

If the image is external and not in WordPress' media library, perhapes:

• a VIP helper function could be created to download only first few bytes of image
• don't use this function, or do image sizing w/ JS or CSS instead

What code should be reported as a violation?

$size = getimagesize( $image_url );
list($width, $height) = getimagesize( $image_url );
//etc.