System and method for efficient scalable stream adaptation

Abstract

A system and method for signaling low-to-high layer switching points in a file format level to enable efficient scalable stream switching in streaming servers and local file playback. The present invention also provides for a system and method for signaling low-to-high layer switching points in video bit stream, e.g., to enable intelligent forwarding of scalability layers in media-aware network elements or computationally scalable decoding in stream recipients.

1 . A method of encoding a sequence of pictures into a sequence of access units, the method comprising:
 encoding a first picture of the sequence of pictures into a first access unit of said sequence of access units, the first access unit comprising a first temporal level value for indicating temporal scalability of the first access unit;   marking a decoded reference picture decodable from the first access unit as used for reference;   encoding, after encoding the first picture, a second picture of the sequence of pictures into a second access unit of said sequence of access units, the second access unit comprising a second temporal level value for indicating temporal scalability of the second access unit;   the first access unit and the second access unit being on the same spatial scalability layer and on the same quality scalability layer; and   in response to the first temporal level value being the same or higher than the second temporal level value, marking the decoded reference picture as unused for reference.   
     
     
         2 . A method of  claim 1 , further comprising:
 encoding an indication corresponding to the second access unit causing a decoding process to mark the decoded reference picture as unused for reference.   
     
     
         3 . A method of decoding a sequence of access units into a sequence of decoded pictures, the method comprising:
 decoding a first access unit of said sequence of access units into a first decoded picture of the sequence of decoded pictures, the first access unit comprising a first temporal level value for indicating temporal scalability of the first access unit;   marking the first decoded picture as used for reference;   decoding, after decoding the first access unit, a second access unit of said sequence of access units into a second decoded picture of the sequence of decoded pictures, the second access unit comprising a second temporal level value for indicating temporal scalability of the second access unit;   the first access unit and the second access unit being on the same spatial scalability layer and on the same quality scalability layer;   comparing the first temporal level value to the second temporal level value; and   marking the first decoded picture as unused for reference in response to the first temporal level value being the same or higher than the second temporal level value.   
     
     
         4 . A method of  claim 3 , further comprising:
 decoding, prior to said comparing, an indication corresponding to the second access unit causing a decoding process to mark the first decoded picture as unused for reference.   
     
     
         5 . An electronic device for encoding a sequence of pictures into a sequence of access units, comprising:
 a processor; and   a memory unit operatively connected to the processor and including a computer program product comprising:
 computer code for encoding a first picture of the sequence of pictures into a first access unit of said sequence of access units, the first access unit comprising a first temporal level value for indicating temporal scalability of the first access unit; 
 computer code for marking a decoded reference picture decodable from the first access unit as used for reference; 
 computer code for encoding, after encoding the first picture, a second picture of the sequence of pictures into a second access unit of said sequence of access units, the second access unit comprising a second temporal level value for indicating temporal scalability of the second access unit, the first access unit and the second access unit being on the same spatial scalability layer and on the same quality scalability layer; and 
 computer code, responsive to the first temporal level value being the same or higher than the second temporal level value, for marking the decoded reference picture as unused for reference. 
   
     
     
         6 . An electronic device of  claim 5 , further comprising:
 computer code for encoding an indication corresponding to the second access unit causing a decoding process to mark the decoded reference picture as unused for reference.   
     
     
         7 . An electronic device for decoding a sequence of access units into a sequence of decoded pictures, comprising:
 a processor; and   a memory unit operatively connected to the processor and including a computer program product comprising:
 computer code for decoding a first access unit of said sequence of access units into a first decoded picture of the sequence of decoded pictures, the first access unit comprising a first temporal level value for indicating temporal scalability of the first access unit; 
 computer code for marking the first decoded picture as used for reference; 
 computer code for decoding, after decoding the first access unit, a second access unit of said sequence of access units into a second decoded picture of the sequence of decoded pictures, the second access unit comprising a second temporal level value for indicating temporal scalability of the second access unit, the first access unit and the second access unit being on the same spatial scalability layer and on the same quality scalability layer; 
 computer code for comparing the first temporal level value to the second temporal level value; and 
 computer code for marking the first decoded picture as unused for reference in response to the first temporal level value being the same or higher than the second temporal level value. 
   
     
     
         8 . An electronic device of  claim 7 , further comprising:
 computer code for decoding, prior to said comparing, an indication corresponding to the second access unit causing a decoding process to mark the first decoded picture as unused for reference.