First picture (the first layer) can be any type of picture (jpeg, png, gif, bmp…), but the second layer (the done icon need to be format like png with transparent background). Of course you need to define the position of the second picture.
VerticalLayout layout = new VerticalLayout();
layout.setSpacing(true);
Image basic = new Image(null, new ThemeResource("icon/home.png"));
layout.addComponent(basic);
Image check = new Image(null, new ThemeResource("icon/check.png"));
check.addStyleName("move-image");
layout.addComponent(check);