Optimized exposure temporal smoothing for time-lapse mode

1. A camera for capturing a time-lapse, comprising:

a processor configured to:

acquire a first frame of the time-lapse;

calculate an exposure setting for a second frame of the time-lapse,

wherein the exposure setting prevents a flickering effect in the time-lapse, and

wherein the exposure setting is determined using one or more preview images that are previewed in a time gap between the first frame and the second frame; and

acquire the second frame of the time-lapse using the exposure setting.

2. The camera of claim 1 , wherein the one or more preview images are not included in the time-lapse.

3. The camera of claim 1 , wherein to determine the exposure setting for the second frame of the time-lapse comprises to:

temporally smooth respective exposure settings of at least some of the one or more preview images.

4. The camera of claim 3 , wherein to temporally smooth the respective exposure settings of the at least some of the one or more preview images comprises to:

temporally smooth every other preview image of the one or more preview images.

5. The camera of claim 3 , wherein to temporally smooth the respective exposure settings of the one or more preview images comprises to:

perform temporal smoothing based on a difference between the second frame of the time-lapse and a last preview image the one or more preview images.

6. The camera of claim 5 , wherein the difference is a luminance difference.

7. The camera of claim 1 , wherein the first frame is acquired in a low-luminance setting and the second frame is acquired in a high-luminance setting.

8. The camera of claim 1 , wherein the first frame is acquired in a high-luminance setting and the second frame is acquired in a low-luminance setting.

9. A method for reducing overexposure or underexposure in a time-lapse, comprising:

acquiring, using an image capture device, a first frame of the time-lapse using a first exposure setting;

obtaining, using the image capture device, a preview image that is not included in the time-lapse using a preview exposure setting;

determining a second exposure setting by smoothing the first exposure setting and the preview exposure setting; and

acquiring, using the image capture device, a second frame of the time-lapse using the second exposure setting.

10. The method of claim 9 , further comprising:

setting a respective auto-exposure setting for a time-lapse mode of the image capture device and at least one of a still mode or a video mode of the image capture device.

11. The method of claim 9 , wherein obtaining, using the image capture device, the preview image comprises:

obtaining a first preview image; and

obtaining a second preview image, wherein the second preview image immediately precedes the second frame and follows the first preview image.

12. The method of claim 11 , wherein determining the second exposure setting by smoothing the first exposure setting and the preview exposure setting comprises:

determining the second exposure setting by continuously smoothing the first exposure setting, a first preview exposure setting of the first preview image, and a second preview exposure setting of the second preview image.

13. The method of claim 11 , wherein the first preview image immediately follows the first frame.

14. The method of claim 9 , wherein obtaining, using the image capture device, the preview image comprises:

setting a preview image capture rate; and

obtaining a plurality of preview images at the preview image capture rate in a time gap between a first capture time of the first frame and a second capture time of the second frame.

15. The method of claim 14 , wherein the preview image capture rate is received from a user of the image capture device.

16. The method of claim 14 , wherein the preview image capture rate is based on at least one of a scene complexity or available compute resources of the image capture device.

17. A non-transitory computer-readable storage medium, comprising executable instructions that, when executed by a processor, facilitate performance of operations for reducing overexposure or underexposure in a time-lapse, the operations comprising operations to:

capture a first frame of the time-lapse using a first exposure setting;

acquire one or more preview images during a time gap between the first frame of the time-lapse and a next frame of the time-lapse, wherein a last preview image of the one or more preview images is acquired using a last exposure setting;

calculate a second exposure setting using the last exposure setting; and

capture the next frame of the time-lapse using the second exposure setting.

18. The non-transitory computer-readable storage medium of claim 17 , wherein the operations further comprise operations to:

continuously estimate a first preview exposure setting for a next preview image of the one or more preview images using a second preview exposure setting of a previous preview image of the one or more preview images.

19. The non-transitory computer-readable storage medium of claim 17 , wherein to calculate the second exposure setting using the last exposure setting comprises to:

apply a damping factor to the second exposure setting.

20. The non-transitory computer-readable storage medium of claim 19 , wherein the damping factor is selected based on a relationship between an exposure difference and a temporal smoothing speed.