twentytwelve header only on homepage

Hi how do i change the below code in my child theme header.php so that the header appears only on homepage

[ Moderator note: Code fixed, please wrap code in backticks or use the code button. ]

<?php if ( get_header_image() ) : ?>
		<a>"><img src="<?php header_image(); ?>" class="header-image" width="<?php echo get_custom_header()->width; ?>" height="<?php echo get_custom_header()->height; ?>" alt="" /></a>
		<?php endif; ?>

Know this is asked alot but when i add the code below seen in other posts nothing happens

<?php if(is_home) { ?>

thank you in advance
Melanie