Earlier today Patently Apple posted a report titled "Mercedes-Benz announced a new collaboration with Apple Music and the Universal Music Group to bring Spatial Audio to non-Apple Audio Systems." Coincidentally, an Apple patent filing was published last Thursday by the U.S. Patent Office titled "Spatial Audio reproduction based on Head-to-Torso Orientation."

Apple's patent relates to a media system and a method of using the media system to reproduce spatial audio based on head-to-torso orientation. The method includes determining a head-to-source orientation and a head-to-torso orientation based on head orientation data generated by a head tracking device. Determining the head-to-torso orientation includes determining torso movements based on movements of the head. The torso can be determined to move when the head movements meet a head movement condition, such as a predetermined angle of movement or pattern of movement. A binaural audio filter that is based on a head-related transfer function (HRTF) corresponding to both the head-to-source orientation and the head-to-torso orientation is applied to an audio input signal to generate an audio output signal. The audio output signal is played to accurately recreate spatial audio having sounds emitted to the user by a sound source.

While the target devices described in the patent filing are primarily AirPods including AirPods Max, the patent does state that the invention will also apply to an iMac (desktop), MacBook (Laptop) and other devices like those which would cover media systems in vehicles.  

Apple’s patent FIG. 1 below is a pictorial view of a user positioned relative to a sound source in a soundscape; FIG. 2 is a flowchart of a method of reproducing spatial audio based on a head-to-torso orientation.

Apple’s patent FIG. 4 below is a pictorial view of a head of a user moving relative to a sound source in a soundscape; FIG. 9 is a pictorial view of a head above torso mesh generation used to simulate a head-related transfer function for various combinations of head-to-source and head-to-torso orientations.

Apple was granted a patent for this invention back in late June that we covered here. Last week the U.S. Patent Office published Apple's added 20 new patent claims to protect their invention. Below are two of the new claims:

New Patent Claim #1: A method, comprising: detecting a head movement of a head of a user based on head orientation data generated by a device; determining a torso movement of a torso based on the head movement, wherein the torso movement differs from the head movement; selecting a head-related transfer function (HRTF) corresponding to the torso movement; and applying a binaural audio filter to an audio input signal to generate an audio output signal, wherein the binaural audio filter is based on the HRTF.

New Patent Claim #11: A media system, comprising: one or more processors configured to: detect a head movement of a head of a user based on head orientation data generated by a device, determine a torso movement of a torso based on the head movement, wherein the torso movement differs from the head movement, select a head-related transfer function (HRTF) corresponding to the torso movement, and apply a binaural audio filter to an audio input signal to generate an audio output signal, wherein the binaural audio filter is based on the HRTF; and one or more speakers configured to play the audio output signal to recreate spatial audio of sounds.

For more details and to review the other 18 new patent claims, review Apple's patent application number US 20220329965.