Change Woocommerce Product Image Size – category dependent

Hello,

We want to show larger product image sizes (when you click into the product itself) for all products in a certain category. I tried the following function…

add_action( 'init', 'yourtheme_woocommerce_image_dimensions', 1 );

/**
 * Define image sizes
 */
function yourtheme_woocommerce_image_dimensions() {

     if (is_product_category('wood-deals')) {

	$single = array(
		'width' 	=> '200',	// px
		'height'	=> '200',	// px
		'crop'		=> 1 		// true
	);
     }

	// Image sizes

	update_option( 'shop_single_image_size', $single ); 		// Single product image
}

Got the code here – https://premium.wpmudev.org/forums/topic/how-can-i-custome-and-fix-woocommerce-product-image-size

This didn’t work. Anyone know how to do this? Thanks in advance.