Head-mounted electronic device with localized flicker detection

1 . A method of operating an electronic device, comprising:

with a plurality of image sensors, acquiring images of a scene;

identifying a region of the images as a candidate region for including a light source;

determining whether the candidate region exhibits a pattern indicative of flicker; and

reducing image artifacts resulting from flicker caused by the light source in the candidate region by adjusting an exposure time for the plurality of image sensors.

2 . The method of claim 1 , further comprising:

sensing one or more dominant flicker frequencies in the scene that are different from a frequency of the flicker of the light source.

3 . The method of claim 1 , further comprising:

with one or more depth sensors, obtaining depth information from the scene, wherein identifying the candidate region comprises identifying the candidate region based on the depth information.

4 . The method of claim 3 , wherein identifying the candidate region comprises identifying a planar surface in the scene based on the depth information.

5 . The method of claim 3 , wherein identifying the candidate region further comprises performing semantic segmentation to identify a region of the images with a display or a screen configured to emit the light source.

6 . The method of claim 1 , wherein identifying the candidate region comprises performing semantic segmentation to identify a region of the images with a display or a screen configured to emit the light source.

7 . The method of claim 1 , wherein the plurality of image sensors comprise roller shutter image sensors, and wherein determining whether the candidate region exhibits a pattern indicative of flicker comprises detecting horizontal bands in the images.

8 . The method of claim 1 , further comprising:

computing a frequency of the light source in the candidate region based on one or more of: the exposure time of the plurality of image sensors, a frame rate of the plurality of image sensors, and a line readout speed of the plurality of image sensors.

9 . The method of claim 8 , wherein adjusting the exposure time for the plurality of image sensors comprises setting the exposure time to a multiple of a flicker period that is equal to a reciprocal of the computed frequency of the light source in the candidate region.

10 . The method of claim 1 , further comprising:

with one or more tracking sensors, obtaining gaze data; and

selectively bypassing the adjustment of the exposure time for reducing image artifacts resulting from flicker caused by the light source in the candidate region based on the gaze data.

11 . A method of operating an electronic device, comprising:

during a first time period, acquiring a first plurality of images with external-facing cameras and identifying a first region in the first plurality of images as a first candidate region for producing local flicker;

during a second time period following the first time period, acquiring a second plurality of images with the external-facing cameras and identifying a second region in the second plurality of images as a second candidate region for producing local flicker;

confirming that the second candidate region corresponds to the first candidate region; and

mitigating the local flicker in the first and second candidate regions by adjusting an exposure time of the external-facing cameras.

12 . The method of claim 11 , further comprising:

determining whether the first candidate region exhibits a pattern indicative of flicker; and

determining whether the second candidate region exhibits a pattern indicative of flicker.

13 . The method of claim 12 , further comprising:

computing a first frequency of the local flicker in the first candidate region; and

computing a second frequency of the local flicker in the second candidate region.

14 . The method of claim 13 , wherein confirming that the second candidate region corresponds to the first candidate regions comprises comparing the first computed frequency to the second computed frequency.

15 . The method of claim 14 , further comprising:

obtaining motion and location information on the electronic device, wherein confirming that the second candidate region corresponds to the first candidate region comprises:

identifying a first planar surface in the first candidate region;

identifying a second planar surface in the second candidate region; and

comparing the first planar surface to the second planar surface based on the motion and location information.

16 . The method of claim 13 , further comprising:

sensing a dominant light source; and

obtaining a frequency of the dominant light source, wherein the frequency of the dominant light source is different than the first computed frequency of the local flicker.

17 . An electronic device comprising:

a plurality of external-facing cameras configured to acquire images of a scene;

one or more displays configured to output the acquired images; and

control circuitry configured to:

identify an area of the acquired images as a candidate region for including a local light source;

determine whether the candidate region exhibits a pattern indicative of flicker; and

mitigate flicker caused by the local light source on the one or more displays by adjusting an exposure time of the plurality of external-facing cameras.

18 . The electronic device of claim 17 , further comprising:

a flicker sensor configured to sense a dominant light source in the scene that is different than the local light source in the candidate region; and

a flicker processor configured to obtain a frequency of the dominant light source.

19 . The electronic device of claim 17 , further comprising:

one or more depth sensors configured to obtain depth information from the scene, wherein the candidate region is identified based on the depth information.

20 . The electronic device of claim 17 , further comprising:

a scene understanding subsystem configured to perform semantic segmentation on the acquired images to generate corresponding labels, wherein the candidate region is identified based on the labels generated from the scene understanding subsystem.

21 . The electronic device of claim 17 , further comprising:

a motion and location determination subsystem configured to output motion and location information associated with the electronic device, wherein the control circuitry is further configured to confirm whether the candidate region exhibits flicker based on the motion and location information.