The caption effect composites arbitrary text on top of the underlying video and effect
tracks. The text appears in a 'safe' area along the bottom of the frame, wrapping to as
many lines as are needed to display all the text at the specified size.
There is also a semi transparent
color placed behind the text, which extends past the safe area to the edge of the frame.
Most elements of the caption can be
controlled including text and background color, text size and padding. The
attribute is also supported to fade the entire effect.
editable: comma delimited list of property names
backalpha: positive float (percentage)
backcolor: six character hex color value
fade: comma delimited pairs of percentages
font: valid font id
forecolor: six character hex color value
id: single word string identifier, starting with a letter
length: floating point number (frames)
padding: integer (pixels)
symbol: a valid SWF URL, followed by an ampersand and class name
text: any string
textsize: positive number (percentage of display height)
type: the string 'effect'