width: 345px; height: 487px; background-image: url("https://photos.smugmug.com/photos/i-PQGcLJ6/0/XL/i-PQGcLJ6-XL.jpg"); background-size: 345px 487px; code example

Example: background image height and width

.class{
	background: url("../images/icons/map.png") no-repeat center center/50px 50px fixed;
}