Method and device for transmitting stereo media content

1. A method for generating a track, the method comprising:

obtaining encoded media data for a track that comprises first and second view frames;

generating descriptive metadata for the track that comprises data for signaling a first coverage information associated to the first view frame and separate data for signaling a second coverage information associated to the second view frame, the first coverage information being related to a first projection of the first view frame on a first sphere, the second coverage information being related to a second projection of the second view frame on a second sphere,

wherein the descriptive metadata include two parameters for signaling different possible coverages for the first or second coverage information respectively, wherein each of the two parameters takes a first value when the respective coverage information defines a coverage for a left view of stereoscopic media data, takes a second value when the respective coverage information defines a coverage for a right view of stereoscopic media data, or takes a third value when the respective coverage information defines the same coverage for both right and left views of stereoscopic media data; and

generating the track comprising the generated descriptive metadata and referencing both the first and second view frames.

2. The method of claim 1 , wherein the first coverage information characterizes a region of the first sphere which is covered by the first projection, wherein the second coverage information characterizes another region of the second sphere which is covered by the second projection.

3. The method of claim 1 , wherein the encoded media data is encoded stereoscopic media data, wherein the first view frames correspond to left view frames and the second view frames correspond to right view frames.

4. The method of claim 1 , further comprising transmitting the track to a client.

5. The method of claim 1 , wherein the descriptive metadata comprise a parameter taking a first predetermined value for signaling that each of the first and second view frames is associated with a different coverage.

6. The method of claim 1 , wherein the track comprises a sample, the sample referencing both the first and second view frames.

7. The method of claim 1 , wherein the track comprises a first sample referencing the first view frame, and a second sample immediately following the first sample and referencing the second view frame.

8. A method for decoding media data comprising view frames, the method comprising:

obtaining a track comprising descriptive metadata and referencing encoded media data comprising first and second view frames, the descriptive metadata comprising data for signaling a first coverage information associated to the first view frame and separate data for signaling a second coverage information associated to the second view frame, the first coverage information being related to a first projection of the first view frame on a first sphere, the second coverage information being related to a second projection of the second view frame on a second sphere,

wherein the descriptive metadata include two parameters for signaling different possible coverages for the first or second coverage information respectively, wherein each of the two parameters takes a first value when the respective coverage information defines a coverage for a left view of stereoscopic media data, takes a second value when the respective coverage information defines a coverage for a right view of stereoscopic media data, or takes a third value when the respective coverage information defines the same coverage for both right and left views of stereoscopic media data; and

decoding the media data.

9. The method of claim 8 , wherein the obtaining step comprises:

determining a third sphere region to process;

determining a coverage information associated to the obtained third sphere region, the coverage information being related to a projection of a view frame on the third sphere;

selecting a track among a plurality of tracks, based on the determined coverage information.

10. The method of claim 8 , further comprising displaying a region of the first sphere covered by the projected first view frame, and/or displaying another region of the second sphere covered by the projected second view frame.

11. The method of claim 8 , wherein the first coverage information characterizes a region of the first sphere which is covered by the first projection, wherein the second coverage information characterizes another region of the second sphere which is covered by the second projection.

12. The method of claim 8 , wherein the encoded media data is encoded stereoscopic media data, wherein the first view frames correspond to left view frames and the second view frames correspond to right view frames.

13. The method of claim 8 , wherein the descriptive metadata comprise a parameter taking a first predetermined value for signaling that each of the first and second view frames is associated with a different coverage.

14. A non-transitory computer-readable storage medium storing a program for causing a computer to execute the method for decoding media data comprising view frames according to claim 8 .

15. A device for generating a track, the device being configured to implement the method according to claim 1 .

16. A device for decoding media data comprising view frames, the device being configured to implement the method according to claim 8 .