Signaling of potential splice points in a video stream

Abstract

In one embodiment the invention provides a method for outputting auxiliary information for use in playing back a video sequence, the method comprising obtaining a measure of usefulness of a particular picture for playing back the video sequence, wherein the measure of usefulness indicates a performance of playing back the video sequence if the particular picture is available in a decoded state at a time of playback versus the particular picture not being available in a decoded state at a time of playback; determining a position in a data stream that includes the video sequence; and storing the auxiliary information at the determined position in the data stream.

1 . A method for splicing from a first video sequence to a second video sequence, wherein each video sequence includes encoded pictures that are decoded into decoded pictures in a decode order, wherein decoded pictures are displayed in a presentation order at picture output times, the method comprising:
 identifying an exit point for the first video sequence, wherein the exit point determines a last frame to display of the first video sequence;   determining a number of pictures of the first video sequence that are already decoded into a decode picture buffer; and   initiating decoding of the second video sequence so that a sufficient number of pictures in the second video sequence are decoded at a time of displaying the last picture from the decode picture buffer sot that displaying of pictures in the second video sequence can begin at a next picture output time.   
   
   
       2 . The method of  claim 1 , wherein the step of determining includes:
 reading a first data field in the first video sequence to obtain a first value, wherein the value indicates a number of consecutive pictures prior to the exit point.   
   
   
       3 . The method of  claim 2 , further comprising:
 reading a second data field in the first video sequence to obtain a second value, wherein the second value indicates a number of decoded pictures in the decoded picture buffer (DPB).   
   
   
       4 . The method of  claim 3 , wherein the second value indicates a
 number of decoded pictures in the DPB that have successive picture output times.   
   
   
       5 . The method of  claim 4 , wherein a first of the successive output times includes a picture output time immediately after the decompression time of a last consecutive picture prior to the exit point as indicated by the first value.