SYSTEM AND METHOD FOR GENERATING A DIGITAL IMAGE

1 . A mobile device, comprising:

a camera module, comprising an image sensor and configured to sample a photographic scene according to a set of exposure parameters comprising an exposure time and an exposure sensitivity;

a strobe unit, configured to illuminate the photographic scene according to a set of strobe parameters comprising a strobe intensity and a strobe color;

a display device, configured to generate a visual display of a digital image;

a touch-input device, configured to receive touch gestures;

a nonvolatile memory circuit; and

one or more processors in communication with the camera module and the strobe unit,

wherein the one or more processors execute instructions to:

cause the strobe unit to emit illumination during a first time interval according to a first set of strobe parameters comprising a first strobe intensity and a first strobe color;

cause the camera module to sample a first image of the photographic scene during the first time interval according to a first set of exposure parameters;

store the first image within an image set;

cause the strobe unit to emit illumination during a second time interval according to a second set of strobe parameters comprising a second strobe intensity and a second strobe color, wherein the second strobe intensity is non-zero and different than the first strobe intensity;

cause the camera module to sample a second image of the photographic scene during the second time interval based on a second set of exposure parameters;

store the second image within the image set;

cause the strobe unit to emit illumination during a third time interval according to a third set of strobe parameters comprising a third strobe intensity and a third strobe color, wherein the third strobe intensity is non-zero and different than the first strobe intensity;

cause the camera module to sample a third image of the photographic scene during the third time interval based on a third set of exposure parameters;

store the third image within the image set;

select an image from the image set;

generate a resulting image by performing a white-balance correction on the selected image; and

store the resulting image in the image set.

2 . The mobile device of claim 1 , wherein the first strobe intensity is non-zero.

3 . The mobile device of claim 1 , wherein the second strobe intensity is the same as the third strobe intensity.

4 . The mobile device of claim 1 , wherein the first strobe color is equal to a measured ambient illumination color.

5 . The mobile device of claim 4 , wherein the first strobe color, the second strobe color, and the third strobe color are equal.

6 . The mobile device of claim 4 , wherein the measured ambient illumination color corresponds to color statistics accumulated while the one or more processors receive image data from the camera module.

7 . The mobile device of claim 1 , wherein the first set of exposure parameters is determined based on ambient illumination.

8 . The mobile device of claim 7 , wherein the first set of exposure parameters, the second set of exposure parameters, and the third set of exposure parameters are equal.

9 . The mobile device of claim 1 , wherein the one or more processors further execute the instructions to display, on the display device, the resulting image.

10 . The mobile device of claim 9 , wherein the one or more processors further execute the instructions to:

display, on the display device, a user interface slider control;

receive, from the touch-input device, a slide gesture directed to the slider control; and

in response to receiving the slide gesture, select the first image and display the first image on the display device.

11 . The mobile device of claim 1 , wherein selecting an image from the image set comprises evaluating exposure quality metric values for images in the image set and selecting one of the images in the image set with a best exposure quality metric value.

12 . The mobile device of claim 11 , wherein the exposure quality metric value comprises a cost function value computed using a cost function, and the best exposure quality metric value corresponds to a lowest cost function value.

13 . The mobile device of claim 12 , wherein the cost function assigns a cost penalty to over-exposed pixels.

14 . The mobile device of claim 1 , wherein the instructions and the image set are stored in the nonvolatile memory circuit.

15 . The mobile device of claim 1 , wherein the third strobe intensity is determined based on the second strobe intensity and exposure statistics, and wherein the exposure statistics comprise at least one of a count of over-exposed pixels, a count of under-exposed pixels, an intensity histogram, or an intensity-weighted sum of pixel intensity.

16 . The mobile device of claim 15 , wherein the exposure statistics are accumulated by a camera interface circuit while the one or more processors receive image data for the second image from the camera module, and wherein the exposure statistics are presented to the one or more processors as memory-mapped storage locations.

17 . The mobile device of claim 15 , wherein the third strobe intensity is determined according to a binary search profile.

18 . A method, comprising:

causing, by one or more processors, a strobe unit to emit illumination into a photographic scene during a first time interval according to a first set of strobe parameters comprising a first strobe intensity and a first strobe color;

causing, by the one or more processors, a camera module to sample a first image of the photographic scene during the first time interval according to a first set of exposure parameters;

storing, by the one or more processors, the first image within an image set;

causing, by the one or more processors, the strobe unit to emit illumination into the photographic scene during a second time interval according to a second set of strobe parameters comprising a second strobe intensity and a second strobe color, wherein the second strobe intensity is non-zero and different than the first strobe intensity;

causing, by the one or more processors, the camera module to sample a second image of the photographic scene during the second time interval based on a second set of exposure parameters;

storing, by the one or more processors, the second image within the image set;

causing, by the one or more processors, the strobe unit to emit illumination into the photographic scene during a third time interval according to a third set of strobe parameters comprising a third strobe intensity and a third strobe color, wherein the third strobe intensity is non-zero and different than the first strobe intensity;

causing, by the one or more processors, the camera module to sample a third image of the photographic scene during the third time interval based on a third set of exposure parameters;

storing, by the one or more processors, the third image within the image set;

selecting, by the one or more processors, an image from the image set;

generating, by the one or more processors, a resulting image by performing a white-balance correction on the selected image; and

storing, by the one or more processors, the resulting image in the image set,

wherein the one or more processors are in communication with the strobe unit and the camera module.

19 . The method of claim 18 , wherein the first strobe color, the second strobe color, and the third strobe color are equal to a measured ambient illumination color.

20 . The method of claim 18 , further comprising:

causing, by the one or more processors, a display device to display the resulting image;

causing, by the one or more processors, a display device to display a user interface slider control;

receiving, by the one or more processors, a slide gesture directed to the slider control; and

in response to receiving the slide gesture:

selecting, by the one or more processors, the first image; and

displaying the first image on the display device.