Decoding Interdependent Frames of a Video Display

Abstract

A module may provide codec-independent services including determining frame display order, frame dependency sets, and queuing the dependency frames in advance so as to enable display of a video. The module enables a video to be played forwards or backwards at a variety of playback speeds from any position within the video. In one implementation, a device communicatively coupled to a plurality of decoders accesses a video that includes a plurality of frames. One or more of the frames are decodable by one or more of the communicatively coupled decoders. The device identifies a frame in the video that is to be displayed, and determines a plurality of dependency frames in the video upon which decoding of the frame to be displayed depends. The device provides an indication that one or more associated dependency frames are to be decoded.

1 . A method comprising:
 identifying a frame in a video that is to be displayed, the video including a plurality of frames, one or more of the frames being decodable by one or more decoders;   queuing one or more frames in the video upon which decoding of the frame to be displayed depends;   receiving respective messages indicating status transitions to a decode status and to a display status, the decode status indicating whether the queued frame will not be, will be or has been decoded and the display status indicating whether the queued frame will not be, will be or has been displayed; and   updating, in response to said receiving the respective messages, a frame state model that indicates, for each of the queued one or more frames of the video, the decode status and the display status.