Method and apparatus for encoding a user interface

Abstract

A method and apparatus for combining video frame sequences with a video display of an interactive program guide (IPG). The apparatus comprises a plurality of compositors that combine background information, video frame sequences and program guide graphics into a single video frame sequence. The sequence is then digitally encoded to form an MPEG-like bitstream. The same background information and informational video is composited with a different program guide graphic to form another video sequence that is also encoded. A plurality of such sequences are produced with each sequence having a different program guide graphic. Each sequence is encoded and then multiplexed into a transport stream such that all the encoded sequences are transmitted to a subscriber's terminal using a single transport stream. As such, the subscriber can transition from one program guide to the next without interruption of the background or video display as the program guide graphic is changed.

1 . A method of encoding a plurality of program guide pages, comprising: 
 encoding each program guide page to form a plurality of program guide page representative bitstreams;    determining a longest bitstream;    associating null packets with at least some of the bitstreams to provide a plurality of bitstreams having substantially similar lengths; and    associating at least one switching packet with the end of each bitstream.    
     
     
         2 . The method of  claim 1 , wherein said plurality of bitstreams are stored in a buffer, said step of determining comprising determining how much of said buffer is occupied by each bitstream.  
     
     
         3 . The method of  claim 2 , further comprising: 
 retrieving the bitstreams from the buffer; and    adapting the retrieved bitstreams to form respective transport streams having substantially similar lengths.    
     
     
         4 . The method of  claim 1 , wherein the NULL packets are added to the bitstreams.  
     
     
         5 . The method of  claim 1 , wherein the switching packets are added to the buffered bitstreams.  
     
     
         6 . The method of  claim 3 , wherein said NULL packets are added to the transport streams.  
     
     
         7 . The method of  claim 3 , wherein said switching packets are added to the transport streams.  
     
     
         8 . The method of  claim 1 , wherein the encoding of each program guide page is performed contemporaneously for program guide pages representing a common time period.  
     
     
         9 . The method of  claim 8 , wherein said switching packets are inserted into switching packets are placed in the bitstreams at a common point.  
     
     
         10 . The method of  claim 9 , wherein the common point represents at least one of a common point in time and a common bitstream byte count.  
     
     
         11 . The method of  claim 1 , wherein the bitstreams are adapted to enable at a decoder a substantially seamless switching between bitstreams.  
     
     
         12 . The method of  claim 11 , wherein the substantially seamless switching between bitstreams enables a visually smooth transition between presented program guide pages.  
     
     
         13 . A method of encoding a plurality of program guide pages comprising the steps of: 
 encoding each program guide page to form a respective bitstream;    buffering the bitstreams for all the guide pages;    retrieving said bitstreams from a buffer;    ordering the bitstreams into a transport stream to equate the length of the transport stream with the length of other transport streams; and    adding switching packets to the transport stream.    
     
     
         14 . A method of encoding a plurality of program guide pages comprising the steps of: 
 contemporaneously encoding each program guide page to form respective bitstreams;    assembling a transport stream containing each bitstream in successive order;    adding switching packets into the transport stream after the bitstreams.