woocommerce_placeholder_img │ filter-hook │ WC 1.0

Usage

add_filter( 'woocommerce_placeholder_img', 'wp_kama_woocommerce_placeholder_img_filter', 10, 3 );

/**
 * Function for `woocommerce_placeholder_img` filter-hook.
 * 
 * @param  $image_html 
 * @param  $size       
 * @param  $dimensions 
 *
 * @return 
 */
function wp_kama_woocommerce_placeholder_img_filter( $image_html, $size, $dimensions ){

	// filter...
	return $image_html;
}

$image_html

-

$size

-

$dimensions

-

Where the hook is called

return apply_filters( 'woocommerce_placeholder_img', $image_html, $size, $dimensions );

Where the hook is used in WooCommerce