Use of objective quality measures of streamed content to reduce streaming bandwidth

Abstract

A method includes encoding video at a first bitrate to produce first encoded sections, and at a second bitrate that is less than the first bitrate to produce second encoded sections. The method further includes measuring levels of objective quality, indicative of perceptual quality, of the first and second encoded sections. The method includes determining, based on the measured objective quality levels, replaceable sections among the first encoded sections, and replacement sections among the second encoded sections, each of the replacement sections to replace a corresponding one of the replaceable sections. the method includes streaming the first encoded sections except for the replaceable sections, and the replacement sections instead of their corresponding replaceable sections.

What is claimed is: 
     
       1. A method of encoding video, the method performed by an encoding system, comprising:
 encoding video at a first bitrate to produce first encoded sections using an encoding system; 
 encoding the video at a second bitrate that is less than the first bitrate to produce second encoded sections using the encoding system, each having encoded therein the video of a corresponding one of the first encoded sections; 
 measuring levels of objective quality levels using the encoding system, indicative of perceptual quality, of the first and second encoded sections; 
 determining, based on the measured objective quality levels, non-replaceable sections among the first encoded sections and replaceable sections among the first encoded sections, and replacement sections among the second encoded sections using the encoding system, each to replace a corresponding one of the replaceable sections; 
 generating identifying information that identifies the replaceable sections and their corresponding replacement sections in the a first and second container files, respectively, using the encoding system; 
 constructing a file containing (1) the non-replaceable sections from the first encoded sections and (2) the replacement sections from the second encoded sections;  
 streaming the identifying information using the encoding system; and 
 in response to requests from a streaming client device that are dependent on the streamed identifying information, streaming the first encoded non-replaceable sections except for the replaceable sections  using the encoding device, and streaming the replacement sections instead of their corresponding replaceable sections, at a same time as the corresponding replaceable section would have been streamed had the corresponding replaceable section not been replaced wherein the streaming includes streaming from the file the non-replaceable sections, and streaming from the file the replacement sections. 
 
     
     
       2. The method of  claim 1 , wherein the determining includes:
 determining, using the encoding device, if corresponding first and second encoded sections have respective measured objective quality levels that each meet a predetermined criterion of objective quality; and 
 declaring, using the encoding device, the corresponding first and second encoded sections as corresponding replaceable and replacement sections, respectively, if the respective measured objective quality levels each meet the predetermined criterion. 
 
     
     
       3. The method of  claim 2 , wherein the predetermined criterion of objective quality is indicative of an acceptable difference in the perceptual quality levels of the corresponding replaceable and replacement sections when decoded and presented. 
     
     
       4. The method of  claim 2 , wherein the predetermined criterion of objective quality is one of:
 a threshold level of objective quality that must be exceeded by each of the respective measured objective quality levels; and 
 a maximum difference between the respective measured objective quality levels that must not be exceeded. 
 
     
     
       5. The method of  claim 1 , wherein:
 the measuring includes measuring a signal-to-noise ratio (SNR) as the objective quality level; and 
 the determining includes determining whether the measured objective quality levels meet a predetermined criterion that is based on one of an absolute objective quality level and a relative objective quality level. 
 
     
     
       6. The method of  claim 1 , further comprising:
 constructing a first file containing the first encoded sections, including the replaceable sections;   constructing a second file containing the second encoded sections, including the replacement sections; and   wherein the streaming includes:   streaming the first encoded sections, except for the replaceable sections, from the first container file; and   streaming the replacement sections from the second container file.   
     
     
       7. The method of  claim 1 , further comprising constructing a file containing the first encoded sections, except for the replaceable sections which are replaced by their corresponding replacement sections, wherein the streaming includes streaming from the file the first encoded sections, except for the replaceable sections, and the replacement sections. 
     
     
       8. A non-transitory computer readable medium encoded with a computer program, including instructions to cause a processor to:
 encode video at a first bitrate to produce first encoded sections; 
 encode the video at a second bitrate that is less than the first bitrate to produce second encoded sections, each having encoded therein the video of a corresponding one of the first encoded sections; 
 measure objective quality levels, indicative of perceptual quality levels, of the first and second encoded sections; 
 determine, based on the measured objective quality levels, non-replaceable sections among the first encoded sections and replaceable sections among the first encoded sections, and replacement sections among the second encoded sections, each to replace a corresponding one of the replaceable sections; 
 generate identifying information that identifies the replaceable sections and their corresponding replacement sections in the a first and second container files, respectively, using the encoding system; 
 constructing a file containing (1) the non-replaceable sections from the first encoded sections and (2) the replacement sections from the second encoded sections;  
 stream the identifying information; and 
 in response to requests from a playback device that are dependent on the streamed identifying information, stream the first encoded non-replaceable sections except for the replaceable sections, and stream the replacement sections instead of their corresponding replaceable sections, at a same time as the corresponding replaceable section would have been streamed had the corresponding replaceable section not been replaced wherein the streaming includes streaming from the file the non-replaceable sections, and streaming from the file the replacement sections. 
 
     
     
       9. The computer readable medium of  claim 8 , wherein the instructions to cause the processor to determine include instructions to cause the processor to:
 determine if corresponding first and second encoded sections have respective measured objective quality levels that each meet a predetermined criterion of objective quality; and 
 declare the corresponding first and second encoded sections as corresponding replaceable and replacement sections, respectively, if the respective measured objective quality levels each meet the predetermined criterion. 
 
     
     
       10. The computer readable medium of  claim 9 , wherein the predetermined criterion of objective quality is indicative of an acceptable difference in the perceptual quality levels of the corresponding replaceable and replacement sections when decoded and presented. 
     
     
       11. The computer readable medium of  claim 9 , wherein the predetermined criterion of objective quality is one of:
 a threshold level of objective quality that must be exceeded by each of the respective measured objective quality levels; and 
 a maximum difference between the respective measured objective quality levels that must not be exceeded. 
 
     
     
       12. The computer readable medium of  claim 8 , wherein:
 the instructions to cause the processor to measure include instructions to cause the processor to measure a signal-to-noise ratio (SNR) as the objective quality level; and 
 the instructions to cause the processor to determine include instructions to cause the processor to determine whether the measured objective quality levels meet a predetermined criterion that is based on one of an absolute objective quality level and a relative objective quality level. 
 
     
     
       13. The computer readable medium of  claim 8 , wherein the instructions further include instructions to cause the processor to:
 construct a first file containing the first encoded sections, including the replaceable sections;   construct a second file containing the second encoded sections, including the replacement sections; and   wherein the instructions to cause the processor to stream include instructions to cause the processor to:   stream the first encoded sections, except for the replaceable sections, from the first container file; and   stream the replacement sections from the second container file.   
     
     
       14. The computer readable medium of  claim 8 , further comprising constructing a file containing the first encoded sections, except for the replaceable sections which are replaced by their corresponding replacement sections, wherein the streaming includes streaming from the file the first encoded sections, except for the replaceable sections, and the replacement sections. 
     
     
       15. An encoding apparatus, comprising:
 a processor;  
 anda memory configured tostoring computer executable instructions which when executed cause the processor to: 
 encode video at a first bitrate to produce first encoded sections, and encode the video at a second bitrate that is less than the first bitrate to produce second encoded sections, each having encoded therein the video of a corresponding one of the first encoded sections; 
 measure objective quality levels, indicative of perceptual quality levels, of the first and second encoded sections; 
 determine, based on the measured objective quality levels, non-replaceable sections among the first encoded sections and replaceable sections among the first encoded sections, and replacement sections among the second encoded sections, each to replace a corresponding one of the replaceable sections; and 
 generate identifying information that identifies the replaceable sections and their corresponding replacement sections in the a first and second container files, respectively, using the encoding system; 
 construct a file containing (1) the non-replaceable sections from the first encoded sections and (2) the replacement sections rom the second encoded sections;  
 stream the identifying information; and 
 in response to requests from a playback device that are dependent on the streamed identifying information, stream the first encoded non-replaceable sections except for the replaceable sections, and the replacement sections instead of their corresponding replaceable sections, at a same time as the corresponding replaceable section would have been streamed had the corresponding replaceable section not been replaced wherein the streaming includes streaming from the file the non-replaceable sections, and streaming from the file the replacement sections. 
 
     
     
       16. The encoding apparatus of  claim 15 , wherein the processor and memory, configured to determine, are further configured processor when executing the instructions in the memory is further configured to: determine if corresponding first and second encoded sections have respective measured objective quality levels that each meet a predetermined criterion of objective quality; and declare the corresponding first and second encoded sections as corresponding replaceable and replacement sections, respectively, if the respective measured objective quality levels each meet the predetermined criterion. 
     
     
       17. The encoding apparatus of  claim 16 , wherein the predetermined criterion of objective quality is indicative of an acceptable difference in the perceptual quality levels of the corresponding replaceable and replacement sections when decoded and presented. 
     
     
       18. The encoding apparatus of  claim 16 , wherein the predetermined criterion of objective quality is one of: a threshold level of objective quality that must be exceeded by each of the respective measured objective quality levels; and a maximum difference between the respective measured objective quality levels that must not be exceeded. 
     
     
       19. The encoding apparatus of  claim 16 , wherein the processor and memory, configured to measure, are further configured the processor when executing the instructions in the memory is further configured to measure a signal-to-noise ratio (SNR) as the objective quality level; and the processor and memory, configured to determine, are further configured to determine whether the measured objective quality levels meet a predetermined criterion that is based on one of an absolute objective quality level and a relative objective quality level. 
     
     
       20. The apparatus of  claim 16 , wherein:
 the processor and memory are further configured to   construct a first file containing the first encoded sections, including the replaceable sections, and   construct a second file containing the second encoded sections, including the replacement sections; and   the processor and memory, configured to stream, are further configured to   stream the first encoded sections, except for the replaceable sections, from the first container file, and   stream the replacement sections from the second container file.   
     
     
       21. The apparatus of  claim 16 , wherein:
 the processor and memory are further configured to construct a file containing the first encoded sections, except for the replaceable sections which are replaced by their corresponding replacement sections; and   the processor and memory, configured to stream, are further configured to stream from the file the first encoded sections, except for the replaceable sections, and the replacement sections.   
     
     
       22. The encoding apparatus of  claim 15 , further comprising: a communication system to communicate with a network; and a housing to house the processor and memory, and the communication system. 
     
     
       23. A content distribution system, comprising:
 a set of one or more encoding servers, wherein each server of the set of encoding servers comprises:
 a non-volatile storage storing computer executable instructions; and 
 at least one processor; 
   wherein the computer executable instructions, which when executed cause the processors in the set of one or more encoding servers to encode source content by:
 encoding a portion of video at a first bitrate to produce a first encoded section; 
 encoding the same portion of video at a second bitrate that is less than the first bitrate to produce a second encoded section; 
 measuring objective quality levels with respect to each of the first and second encoded sections; 
 selecting one of the first and second encoded sections based on the measured objective quality levels of the first and second encoded sections; 
 constructing a file containing the selected one of the first and second encoded sections, wherein the file contains at least one encoded section encoded at the first bitrate and at least one encoded section encoded at the second bitrate; 
 storing a video stream comprising the file containing the selected one of the first and second encoded sections; and 
 streaming the stored video stream in response to a request from a playback device.  
   
     
     
       24. The content distribution system of claim 23, wherein the first and second sections encode video at a same resolution.  
     
     
       25. The content distribution system of claim 23, wherein the first and second encoded sections are each a self-contained unit of media capable of being decoded without reference to any other encoded section.  
     
     
       26. The content distribution system of claim 25, wherein the video stream comprises a plurality of encoded sections including the selected one of the first and second encoded sections and each of the plurality of encoded sections encodes a fixed duration of media.  
     
     
       27. The content distribution system of claim 25, wherein the video stream comprises a plurality of encoded sections including the selected one of the first and second encoded sections and at least some of the plurality of encoded sections encode different durations of media.  
     
     
       28. The content distribution system of claim 23, wherein each of the first and second encoded sections comprises a number of successive frames of video.  
     
     
       29. The content distribution system of claim 23, wherein a measured objective quality of a section of video is at least one measure selected from the group consisting of: a signal-to-noise ratio (SNR) of the section, a peak SNR (PSNR) of the section, and a structural similarity index (SSIM) that measures a similarity between sections.  
     
     
       30. The content distribution system of claim 23, wherein the processor when executing the instructions in the memory is further configured to encode source content by:
 determining when the second encoded section has a respective measured objective quality level that meets a predetermined criterion for objective quality; and   selecting the corresponding second encoded section when the measured objective quality level meets the predetermined criterion.    
     
     
       31. The content distribution system of claim 30, wherein the predetermined criterion of objective quality is indicative of an acceptable difference in the perceptual quality levels of the corresponding first and second sections when decoded and presented.  
     
     
       32. The content distribution system of claim 30, wherein the measuring includes measuring a signal-to-noise ratio (SNR) as the objective quality level; and the determining includes determining whether the measured objective quality level meet a predetermined criterion that is based on one of an absolute objective quality level and a relative objective quality level.  
     
     
       33. A content distribution system, comprising:
 a set of one or more encoding servers, wherein each server of the set of encoding servers comprises:
 a non-volatile storage storing computer executable instructions; and 
 at least one processor; 
   wherein the computer executable instructions, which when executed, cause the processor to encode source content by:
 encoding a portion of video at a first bitrate to produce a first encoded section, where the first encoded section is a self-contained unit of media capable of being decoded without reference to any other encoded section; 
 encoding the same portion of video at a second bitrate that is less than the first bitrate to produce a second encoded section, where the second encoded section is a self-contained unit of media capable of being decoded without reference to any other encoded section; 
 measuring objective quality levels with respect to each of the first and second encoded sections; 
 determining when the second encoded section has a respective measured objective quality level that meets a predetermined criterion for objective quality; 
 selecting one of the first and second encoded sections based on the measured objective quality levels of the first and second encoded sections, where the second encoded section is selected when the measured objective quality level of the second encoded section meets the predetermined criterion for objective quality; and; 
 constructing a file containing the selected one of the first and second encoded sections, wherein the file contains at least one encoded section encoded at the first bitrate and at least one encoded section encoded at the second bitrate; 
 storing a video stream comprising the file containing the selected one of the first and second encoded sections; 
 streaming the stored video stream in response to a request from a playback device.