How do I include javascript/jquery image resizing with wordpress?

Download the script (or add it via npm > bower to your theme), wp_enqueue_script() it at the wp_enqueue_scripts hook and then simply add/enqueue another (your custom) script where you add the contents of the demo index.html file:

( function( $ ) {
    $( "img" ).photoResize( {
        bottomSpacing: 15
    } );
} )( jQuery || {} );