If the backgroundColor attribute is absent, the background is transparent. This attribute does not have a 1-1 mapping onto a CSS2 property, but can be simulated in CSS2. The object's left top corner is positioned at the top-left coordinates of the box, and empty space at the left or bottom is filled up with the background color. A scrolling mechanism should be invoked when the element's rendered contents exceed its bounds. Depending on the exact situation, either a horizontal or a vertical slice of the visual media object is displayed.
Overflow width is clipped from the right of the media object.
Overflow height is clipped from the bottom of the media object. The default value is zero. This attribute offers advisory information about the element for which it is set. Values of the title attribute may be rendered by user agents in a variety of ways. Authoring tools should ensure that no element can be introduced into a SMIL document without this attribute.