Patent ID: 7415192
Filing Date: 2008-08-19
Classification: G11B,H04N

Abstract:
1. A reproduction apparatus for reproducing a digital stream generated by multiplexing a video stream and a graphics stream, the reproduction apparatus comprising: a video decoder operable to decode the video stream to generate a moving picture; and a graphics decoder operable to decode the graphics stream to generate graphics, and overlay the graphics and the moving picture, wherein: the graphics decoder includes an object buffer for storing the graphics generated by the decoding; the graphics stream includes a plurality of display sets each of which includes a presentation composition segment and an object definition segment for providing a new graphics object to the object buffer; if an active period of the presentation composition segment in the display set overlaps with an active period of a presentation composition segment in a succeeding display set on a reproduction time axis of the video stream, the graphics decoder is able to provide, to the object buffer, a graphics object that is to be referenced by the presentation composition segment in the succeeding display set, by decoding the object definition segment in the display set, if a predetermined condition is satisfied; and the predetermined condition is that the graphics object provided to the object buffer by the display set is not updated to a different graphics object by the succeeding display set.