Optimized exposure temporal smoothing for time-lapse mode
Generating a time-lapse is disclosed. A method includes acquiring, using a camera, a first frame of the time-lapse; acquiring, using the camera, one or more preview images, the preview images are not included in the time-lapse; determining an exposure setting for a second frame of the time-lapse using the one or more preview images; and acquiring, using the camera, the second frame of the time-lapse using the exposure setting. A camera includes a memory and a processor. The processor is configured to execute instructions stored in the memory to acquire a first frame of the time-lapse; acquire one or more preview images, the preview images are not included in the time-lapse; determine an exposure setting for a second frame of the time-lapse using the one or more preview images; and acquire the second frame of the time-lapse using the exposure setting.
1. A method for generating a time-lapse, comprising:
acquiring, using a camera, a first frame of the time-lapse;
acquiring, using the camera and after acquiring the first frame, one or more preview images, wherein the preview images are not included in the time-lapse;
determining an exposure setting for a second frame of the time-lapse using the one or more preview images; and
acquiring, using the camera and after acquiring the one or more preview images, the second frame of the time-lapse using the exposure setting.
2. The method of claim 1 ,
wherein the one or more preview images comprises a last preview image that is taken immediately before the second frame, and
wherein determining the exposure setting for the second frame of the time-lapse using the one or more preview images comprises:
determining the exposure setting based on a last exposure setting of the last preview image.
3. The method of claim 2 ,
wherein the one or more preview images further comprises a first preview image that is taken immediately after the first frame, and
wherein determining the exposure setting for the second frame of the time-lapse using the one or more preview images comprises:
temporally smoothing the one or more preview images between the first preview image and the last preview image.
4. The method of claim 3 , wherein determining the exposure setting for the second frame of the time-lapse using the one or more preview images further comprises:
temporally smoothing the first frame and the last preview image.
5. The method of claim 4 , wherein determining the exposure setting for the second frame of the time-lapse using the one or more preview images further comprises:
applying a damping factor to the exposure setting, wherein the damping factor is based on a first exposure setting of the first frame and a second exposure setting of the last preview image.
6. The method of claim 5 , wherein the damping factor is an adaptive temporal factor that adapts to a difference between the first exposure setting of the first frame and the second exposure setting of the last preview image.
7. The method of claim 6 , wherein the damping factor is based on a difference of luminosity between the first frame and the last preview image.
8. A camera for generating a time-lapse, comprising:
a memory; and
a processor, the processor configured to execute instructions stored in the memory to:
acquire a first frame of the time-lapse;
acquire, after the first frame, one or more preview images, wherein the preview images are not included in the time-lapse;
determine an exposure setting for a second frame of the time-lapse using the one or more preview images; and
acquire, after the one or more preview images, the second frame of the time-lapse using the exposure setting.
9. The camera of claim 8 ,
wherein the one or more preview images comprises a last preview image that is taken immediately before the second frame, and
wherein to determine the exposure setting for the second frame of the time-lapse using the one or more preview images comprises to:
determine the exposure setting based on a last exposure setting of the last preview image.
10. The camera of claim 9 ,
wherein the one or more preview images further comprises a first preview image that is taken immediately after the first frame, and
wherein to determine the exposure setting for the second frame of the time-lapse using the one or more preview images comprises to:
temporally smooth the one or more preview images between the first preview image and the last preview image.
11. The camera of claim 10 , wherein to determine the exposure setting for the second frame of the time-lapse using the one or more preview images further comprises to:
temporally smooth the first frame and the last preview image.
12. The camera of claim 11 , wherein to determine the exposure setting for the second frame of the time-lapse using the one or more preview images further comprises to:
apply a damping factor to the exposure setting, wherein the damping factor is based on a first exposure setting of the first frame and a second exposure setting of the last preview image.
13. The camera of claim 12 , wherein the damping factor is an adaptive temporal factor that adapts to a difference between the first exposure setting of the first frame and the second exposure setting of the last preview image.
14. The camera of claim 13 , wherein the damping factor is based on a difference of luminosity between the first frame and the last preview image.
15. A non-transitory computer-readable storage medium, comprising executable instructions that, when executed by a processor, facilitate performance of operations comprising:
acquiring, using a camera, a first frame of a time-lapse;
acquiring, using the camera and after acquiring the first frame, one or more preview images, wherein the preview images are not included in the time-lapse;
determining an exposure setting for a second frame of the time-lapse using the one or more preview images; and
acquiring, using the camera and after acquiring the one or more preview images, the second frame of the time-lapse using the exposure setting.
16. The non-transitory computer-readable storage medium of claim 15 ,
wherein the one or more preview images comprises a last preview image that is taken immediately before the second frame, and
wherein determining the exposure setting for the second frame of the time-lapse using the one or more preview images comprises:
determining the exposure setting based on a last exposure setting of the last preview image.
17. The non-transitory computer-readable storage medium of claim 16 ,
wherein the one or more preview images further comprises a first preview image that is taken immediately after the first frame, and
wherein determining the exposure setting for the second frame of the time-lapse using the one or more preview images comprises:
temporally smoothing the one or more preview images between the first preview image and the last preview image.
18. The non-transitory computer-readable storage medium of claim 17 , wherein determining the exposure setting for the second frame of the time-lapse using the one or more preview images further comprises:
temporally smoothing the first frame and the last preview image.
19. The non-transitory computer-readable storage medium of claim 18 , wherein determining the exposure setting for the second frame of the time-lapse using the one or more preview images further comprises:
applying a damping factor to the exposure setting, wherein the damping factor is based on a first exposure setting of the first frame and a second exposure setting of the last preview image.
20. The non-transitory computer-readable storage medium of claim 19 , wherein the damping factor is an adaptive temporal factor that adapts to a difference between the first exposure setting of the first frame and the second exposure setting of the last preview image, wherein the damping factor is based on a difference of luminosity between the first frame and the last preview image.