Abstract: A method and computing device for determining the location of a point of interest in a media stream. The method receives an order of duplication for a media stream and a sequence of caption data strings associated with the media stream. The method computes a hash value for a selected string in the sequence. The hash value representing the selected string, and a number of strings in the sequence that immediately precede the selected string, where the order of duplication determines the number of strings. The method receives a media stream time for the selected string based on the hash value, and determines a time at a point of interest in the media stream relative to the media stream time for the selected string.

Abstract: A method of modifying a digital data stream composed of a sequence of frames, where each frame represents an image and includes a data field specifying a presentation time stamp value for the frame. If there is a discontinuity in presentation time stamp value between a next frame and a first frame, a value representing a stream time stamp of interest is assigned to a variable for representing the value of the stream time stamp of interest at a point of discontinuity in presentation time stamp, and a value of the presentation time stamp is assigned to a variable for representing the first frame's clock time based on presentation time stamp, and the next frame is stored in a database using as an index the value representing a stream time stamp of interest.

Abstract: A method of processing a sequence of coded video frames conveyed by a digital data stream, where each frame represents an image, includes receiving the sequence of coded video frames at a recording device, determining a frame interval between presentation of an ith coded frame of the sequence and an (i+1)th coded frame of the sequence, calculating a stream time stamp for the ith coded frame, and calculating a stream time stamp for the (i+1)th coded video frame based on the stream time stamp for the ith coded video frame and the previously determined frame interval.