Predictive bitrate selection for 360 video streaming
Predictive pre-fetching of streams for 360 degree video is described. User view orientation metadata is obtained for a 360 degree video stream that includes data for a plurality of viewports. Data corresponding to one or more high-resolution frames for a particular one of the viewports is pre-fetched based on the user view orientation metadata and those frames are displayed. The high resolution frames are characterized by a higher resolution than for remaining viewports.
1. A method comprising:
a) obtaining view orientation metadata for a 360 degree video stream that includes data for a plurality of viewports;
b) pre-fetching data corresponding to one or more high-resolution frames for a particular viewport of the plurality of viewports determined by the user view orientation metadata;
c) displaying the one or more high-resolution frames, wherein the one or more high resolution frames are characterized by a higher resolution than for remaining viewports of the plurality of viewports
d) checking the user view orientation metadata against an actual user view orientation; and disabling pre-fetching when the user view orientation metadata does not coincide with the actual user view orientation during display.
2. The method of claim 1 wherein the user view orientation metadata is an Author-defined pre-fetch vector.
3. The method of claim 1 wherein the user view orientation metadata is a pre-fetch vector created to match production effects in a scene of the 360 degree video stream.
4. The method of claim 1 wherein the view orientation metadata is a predictive probability of a viewport frame change.
5. The method of claim 4 wherein the predictive probability is generated by a focus group.
6. The method of claim 4 wherein the predictive probability is generated using user generated frame location data.
7. The method of claim 4 wherein the predictive probability also includes an Author defined pre-fetch vector.
8. The method of claim 7 wherein the Author defined pre-fetch vector is a weight applied to the probability of a viewport frame change.
9. The method of claim 4 wherein said pre-fetching frames includes applying a first threshold to the user view orientation metadata to determine the particular viewport of the plurality of viewports.
10. The method of claim 4 wherein the predictive probability of a viewport frame change is a probability for a Markov model.
11. The method of claim 1 wherein the user view orientation metadata is a movement vector.
12. The method of claim 9 wherein b) includes prefetching intermediate resolution frames when the predictive probability exceeds a second threshold.
13. The method of claim 1 , wherein the user view orientation metadata represents a probability of where a user is likely to look.
14. The method of claim 1 , wherein the user view orientation metadata represents a probability of where a user is not likely to look.
15. The method of claim 13 wherein disabling pre-fetching when the user view orientation metadata does not coincide with the actual user view orientation during display includes applying a missed frame threshold to determine whether to disable prefetching.
16. The method of claim 1 wherein prefetching data corresponding to one or more high-resolution frames determined by the user view orientation metadata includes pre-fetching a frame that has a higher resolution section that the rest of the frame.
17. A non-transient computer readable medium containing program instructions for causing a computer to perform the method of:
a) obtaining a user view orientation metadata for a 360 degree video stream that includes data for a plurality of viewports;
b) pre-fetching data corresponding to one or more high-resolution frames for a particular viewport of the plurality of viewports determined by the user view orientation metadata;
c) displaying the one or more high-resolution frames, wherein the one or more high resolution frames are characterized by a higher resolution than for remaining viewports of the plurality of viewports
d) checking the user view orientation metadata against an actual user view orientation; and disabling pre-fetching when the user view orientation metadata does not coincide with the actual user view orientation during display.
18. A system, comprising:
a processor;
a display coupled to the processor;
a memory coupled to the processor having processor-executable instructions embodied therein, the instructions being configured to implement a method upon execution by the processor, the method comprising:
a) obtaining a user view orientation metadata for a 360 degree video stream that includes data for a plurality of viewports;
b) pre-fetching data corresponding to one or more high-resolution frames for a particular viewport of the plurality of viewports determined by the user view orientation metadata;
c) displaying the one or more high-resolution frames with the display, wherein the one or more high resolution frames are characterized by a higher resolution than for remaining viewports of the plurality of viewports
d) checking the user view orientation metadata against an actual user view orientation; and disabling pre-fetching when the user view orientation metadata does not coincide with the actual user view orientation during display.
19. The system of claim 18 wherein the display is a 360 degree display configured to display the plurality of viewports simultaneously.