User experience localizing binaural sound during a telephone call

1. A method that improves a user experience during a video call between a first user and a second user when the first user holds a handheld portable electronic device (HPED) less than one meter away from a face of the first user, the method comprising:

displaying, on a display of the HPED and while the first user holds the HPED less than one meter away from the face of the first user, the second user engaged in the video call with the first user; and

improving the user experience of the first user during the video call by convolving, with a processor, a voice of the second user with far-field head related transfer functions (HRTFs) to a location behind the HPED relative to the face of the first user while the HPED is a near-field distance from the face of the first user.

2. The method of claim 1 further comprising:

sensing, with the HPED, a flick rotation of at least ninety degrees (90°) of the HPED while the first user holds the HPED; and

switching, in response to sensing the flick rotation, from providing the voice of the second user to the first user in the binaural sound to providing the voice of the second user to the first user in one of mono sound or stereo sound.

3. The method of claim 1 further comprising:

capturing, with a camera in the HPED, a head orientation of the first user; and

changing the voice of the second user from localizing as the binaural sound to localizing inside a head of the first user in response to the HPED detecting a change in the head orientation of forty-five (45°) along one of an azimuth direction or an elevation direction.

4. The method of claim 1 further comprising:

detecting, with a camera in the HPED, a change in a head orientation with respect to the display of the HPED; and

providing, in response to detecting the change in the head orientation with respect to the display of the HPED, the voice of the second user to the first user in one of mono sound and stereo sound.

5. The method of claim 1 further comprising:

detecting, with a camera in the HPED, when a lens of the camera is blocked;

ceasing, in response to detecting that the lens of the camera is blocked, to provide the voice of the second user to the first user in the binaural sound; and

providing, in response to detecting that the lens of the camera is blocked, the voice of the second user to the first user in one of mono sound and stereo sound.

6. The method of claim 1 , wherein the location is in empty space and is located directly behind the HPED and on a line-of-sight of the first user that has an azimuth angle (θ) of zero degrees (0°).

7. The method of claim 1 , wherein the location behind the HPED is located along a line-of-sight in which a distance (d 1 ) from a face of the first user to the HPED is 0.0 meters<d 1 ≤0.5 meters and a distance (d 2 ) from the face of the first user to the location is 1.0 meters≤d 2 ≤1.5 meters.

8. A method that improves a user experience during a telephone call between a first user and a second user, the method comprising:

displaying, to the first user and on a display of a handheld portable electronic device (HPED), an image of the second user during the telephone call; and

improving the user experience of the first user during the telephone call by convolving, with a processor, a voice of the second user with far-field head related transfer functions (HRTFs) to a location behind the HPED relative to the first user while the HPED is a near-field distance from a face of the first user.

9. The method of claim 8 further comprising:

detecting, with the HPED, a rotation of at least ninety degrees (90°) of the HPED; and

changing, in response to sensing the rotation, the voice of the second user from being in the binaural sound to being in one of mono sound and stereo sound.

10. The method of claim 8 further comprising:

detecting, with a camera in the HPED, that the face of the first user is less than one meter away from the HPED during the telephone call, wherein the processor convolves the voice of the second user to the location that is behind the HPED in response to detecting that the face of the first user is less than one meter away from the HPED.

11. The method of claim 8 further comprising:

capturing, with a camera in the HPED, the face of the first user;

recognizing, with facial recognition and based on the face captured with the camera, the face of the first user;

retrieving, based on recognizing the face captured with the camera, the far-field HRTFs that are stored in memory and assigned to the face; and

changing the voice of the second user from localizing as the binaural sound to localizing as one of mono sound or stereo sound when the face of the first user is no longer recognized in images captured with the camera.

12. The method of claim 8 further comprising:

detecting, with a camera in the HPED, when a head of the first user moves so the first user is no longer looking at the HPED; and

providing, in response to detecting that the first user is no longer looking at the HPED, the voice of the second user to the first user in one of mono sound and stereo sound.

13. The method of claim 8 further comprising:

detecting, with a camera in the HPED, a right facial profile of the first user; and

moving, in response to detecting the right facial profile, the location where the voice of the second user localizes to the first user to having a location with an azimuth coordinate (θ) of greater than positive seventy degrees (+70°) and less than positive one hundred degrees (+100°) such that +70°≤θ≤100° with respect to a line-of-sight of the first user.

14. The method of claim 8 further comprising:

simultaneously displaying, on the display of the HPED, the image of the second user side-by-side with an image of the first user; and

providing the location behind the HPED where the voice of the second user localizes to the first user at an angle with respect to a line-of-sight that extends to a center of the display of the HPED.

15. A method that improves a user experience when a first user and a second user talk to each other in a telephone call, the method comprising:

displaying, on a display of a handheld portable electronic device (HPED), the second user to the first user during the telephone call;

capturing, with a camera in the HPED, a face of the first user during the telephone call; and

improving the user experience of the first user during the telephone call by convolving, with a processor and with head related transfer functions (HRTFs) having a coordinate location behind the HPED, a voice of the second user so the voice of the second user localizes to the first user as binaural sound, wherein the coordinate location of the HRTFs does not occur at a location of the HPED but a location behind the HPED along a line-of-sight from the first user to the location behind the HPED.

16. The method of claim 15 further comprising:

detecting, with an accelerometer in the HPED, a rotation of the HPED; and

changing, in response to sensing the rotation, the voice of the second user from being in the binaural sound to being in one of mono sound and stereo sound.

17. The method of claim 15 further comprising:

tracking, with a camera in the HPED, the first user during the telephone call; and

automatically switching the voice of the second user from the binaural sound to one of mono sound or stereo sound when the first user moves greater than two meters away from the HPED.

18. The method of claim 15 further comprising:

tracking, with a camera in the HPED, movements of a head of the first user; and

changing the voice of the second user from the binaural sound to mono sound and from the mono sound back to the binaural sound as the movements of the head change from being directed toward the HPED to being directed away from the HPED.

19. The method of claim 15 further comprising:

determining, with the HPED and based on the face captured with the camera, that the HPED is located in front of the face of the first user and less than one meter away from the face of the first user during the telephone call, wherein the processor convolves the voice of the second user to localize to the location that is in front of the face of the first user and farther than the HPED in response to determining that the HPED is located in front of the face of the first user and less than one meter away from the face of the first user.

20. The method of claim 15 , wherein the location behind the HPED is a distance (d) from the HPED such that d≥0.5 meters.