Methods and apparatus for providing a media stream quality signal

• US 9,191,284 B2
• Filed: 10/28/2011
• Issued: 11/17/2015
• Est. Priority Date: 10/28/2010
• Status: Active Grant

• Current Assignee: NetScout Systems Texas, LLC (NetScout Systems Incorporated)
• Original Assignee: Avvasi Inc (NetScout Systems Incorporated)
• Inventors: Kordasiewicz, Roman, Joch, Anthony, Goertz, Kevin, Gallant, Michael
• Primary Examiner(s): Ibrahim, Mohamed
• Application Number:
  US13/283,898
• Publication Number:
  US 20120117225A1
• Time in Patent Office: 1,481 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: H04L 41/145 involving simulating, designing, planning or modelling of a network
• CPC Class Codes: H04L 41/5025 by proactively reacting to service quality change, e.g. by reconfiguration after service quality degradation or upgrade
• CPC Class Codes: H04L 43/0894 Packet rate
• CPC Class Codes: H04L 65/1083 In-session procedures
• CPC Class Codes: H04L 65/1095 Inter-network session transfer or sharing
• CPC Class Codes: H04L 65/756 adapting media to device capabilities
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04N 17/004 for digital television systems
• CPC Class Codes: H04N 21/44004 involving video buffer management, e.g. video decoder buffer or video display buffer
• CPC Class Codes: H04N 21/44209 Monitoring of downstream path of the transmission network originating from a server, e.g. bandwidth variations of a wireless network arrangements for maintenance or administration in data switching networks involving bandwidth and capacity management H04L41/0896

Abstract

Systems, methods and apparatus are provided for computing quality scores for a media session delivered using an adaptive streaming protocol, where the quality score may be an estimate of a mean opinion score. The quality score reflects the impact of network delivery on a viewer'"'"'s quality of experience (QoE). In particular, the quality score is generally based on the effects of stream switch events, as stream switches may be the result of impaired network delivery. Other network events, such as re-buffering events may also be incorporated in the score.

Claims

1. A method of providing a media stream quality signal, the method comprising:

monitoring, at a network monitoring device, a media stream transmitted in a media streaming session between a transmitting device and a receiving device via a network;

modeling, at the network monitoring device, a video player buffer state of the receiving device based on the media streaming session;

determining, at the network monitoring device, a receiving device playback state of the receiving device based on behavior of the modeled video player buffer state;

based on the modeled video player buffer state and the receiving device playback state, estimating, at the network monitoring device, a location in the media streaming session of a stream switch event, at which the receiving device changes playback from a first operating point to a second operating point of the media stream, wherein the media stream is an adaptive bitrate stream that has a plurality of operating points; and

generating at least one key performance indicator based on the location in the media streaming session of the stream switch event.

2. The method of claim 1, further comprising:

updating a presentation quality signal based on the stream switch event;

determining whether a quality change event has occurred based on at least one property of the presentation quality signal exceeding a predetermined threshold; and

if a quality change event has occurred, updating an adjustment signal based on the presentation quality signal and the quality change event.

3. The method of claim 2, further comprising updating a delivery quality signal for the media streaming session based on the adjustment signal.

4. The method of claim 3, further comprising:

updating a user model state based on the receiving device playback state; and

updating the adjustment signal based on the user model state.

5. The method of claim 4, wherein the user model state is determined based on one or more playback events selected from the group consisting of a frequency of re-buffering events, a duration of re-buffering events, an event location within the media stream, a duration of the media streaming session, a start-up delay for the media streaming session and a type of the media streaming session.

6. The method of claim 4, wherein the user model state is determined based at least on the stream switch event.

7. The method of claim 3, wherein the predetermined threshold is based on one or more parameters selected from the group consisting of:

a duration of a change in the presentation quality signal;

a magnitude of a change in the presentation quality signal;

a rate of change in the presentation quality signal in a predetermined time window; and

combinations thereof.

8. The method of claim 2, wherein determining whether the quality change event has occurred is further based on a configuration parameter associated with the media streaming session.

9. The method of claim 8, wherein the configuration parameter is a receiving device configuration parameter.

10. The method of claim 8, wherein the configuration parameter is a transmitting device configuration parameter.

11. The method of claim 2, further comprising:

determining that the presentation quality signal has not changed in a predetermined period;

determining whether the operating point corresponds to a best operating point for the media stream; and

if the operating point does not correspond to the best operating point, update the adjustment signal.

12. The method of claim 1, further comprising determining that the stream switch event corresponds to a change from a first operating point to a second operating point in the plurality of operating points.

13. The method of claim 12, wherein the plurality of operating points are defined by an operating point characteristic selected from the group consisting of a video resolution, a video bit rate, a video frame rate, an audio sample rate, a number of audio channels, an audio bit rate, a receiving device type, a receiving device screen size, and combinations thereof.

14. The method of claim 1, further comprising:

detecting a re-buffering event in the media streaming session; and

generating the at least one key performance indicator based on the re-buffering event.

15. The method of claim 14, wherein the at least one key performance indicator is selected from the group consisting of a number of re-buffering events, a location in the media stream, a duration of re-buffering events, and a start-up delay for the media streaming session.

16. The method of claim 1, wherein the at least one key performance indicator selected from the group consisting of a number of stream switch events, a location in the media stream, a duration of the stream switch event, and a change in operating point for the stream switch event.

20. The apparatus of claim 16, wherein the processor is further configured to:

update a user model state based on the receiving device playback state; and

update the adjustment signal based on the indication based on the receiving device playback state.

21. The apparatus of claim 20, wherein the user model state is determined based on one or more playback events selected from the group consisting of a frequency of re-buffering events, a duration of re-buffering events, a re-buffering location within the media stream, a duration of the media streaming session, a start-up delay for the media streaming session and a type of the media streaming session.

22. The apparatus of claim 20, wherein the user model state is determined based at least on the stream switch event.

17. An apparatus for providing a media stream quality signal, the apparatus comprising a memory and a processor, the processor configured to:

monitor a media stream transmitted in a media streaming session between a transmitting device and a receiving device via a network;

model, at the network monitoring device, a video player buffer state of the receiving device based on the media streaming session;

determine, at the network monitoring device, a receiving device playback state of the receiving device based on behavior of the modeled video player buffer state;

based on the modeled video player buffer state and the receiving device playback state, estimate, at the network monitoring device, a location in the media streaming session of a stream switch event, at which the receiving device changes playback from a first operating point to a second operating point of the media stream, wherein the media stream is an adaptive bitrate stream that has a plurality of operating points; and

generate at least one key performance indicator based on the location in the media streaming session of the stream switch event.

18. The apparatus of claim 17, wherein the processor is further configured to:

update a presentation quality signal based on the stream switch event;

determine whether a quality change event has occurred based on at least one property of the presentation quality signal exceeding a predetermined threshold; and

if a quality change event has occurred, update an adjustment signal based on the presentation quality signal and the quality change event.

19. The apparatus of claim 18, wherein the processor is further configured to update a delivery quality signal based on the adjustment signal.

23. The apparatus of claim 19, wherein the predetermined threshold is based on one or more parameters selected from the group consisting of:

a duration of a change in the presentation quality signal;

a magnitude of a change in the presentation quality signal;

a rate of change in the presentation quality signal in a predetermined time window; and

combinations thereof.

24. The apparatus of claim 18, wherein determining whether the quality change event has occurred is further based on a configuration parameter associated with the media streaming session.

25. The apparatus of claim 24, wherein the configuration parameter is a receiving device configuration parameter.

26. The apparatus of claim 24, wherein the configuration parameter is a transmitting device configuration parameter.

27. The apparatus of claim 18, wherein processor is further configured to:

determine that the presentation quality signal has not changed in a predetermined period;

determine whether the operating point corresponds to a best operating point for the media stream; and

if the operating point does not correspond to the best operating point, update the adjustment signal.

28. The apparatus of claim 18, wherein the processor is further configured to:

detect a re-buffering event in the media streaming session; and

generate the at least one key performance indicator based on the re-buffering event.

29. The apparatus of claim 28, wherein the at least one key performance indicator is selected from the group consisting of a number of re-buffering events, a location in the media stream, a duration of re-buffering events, and a start-up delay for the media streaming session.

30. The apparatus of claim 17, wherein the processor is further configured to determine that the stream switch event corresponds to a change from a first operating point to a second operating point in the plurality of operating points.

31. The apparatus of claim 30, wherein the plurality of operating points are defined by an operating point characteristic selected from the group consisting of a video resolution, a video bit rate, a video frame rate, an audio sample rate, a number of audio channels, an audio bit rate, a receiving device type, a receiving device screen size, and combinations thereof.

32. The apparatus of claim 17, wherein the at least one key performance indicator is selected from the group consisting of a number of stream switch events, a location in the media stream, a duration of the stream switch event, and a change in operating point for the stream switch event.