Automatic white balancing system and method
Systems for automatic white balancing (AWB) of a digital image and methods for making and using same. In response to a white balancing trigger, the relative positions of an image sensor and a reference region for white balancing are automatically adjusted such that the image sensor can acquire an image of the reference region. A white balance parameter reflecting the color temperature of the illuminating source is then computed and used to perform white balancing so as to remove color casts. The position of the reference region can be pre-recorded or scanned-for by the image sensor. The reference region can be rendered mobile so that it can be positioned within the image sensor's field-of-vision. The imaging systems can further include a gimbal that enables the image sensor to rotate about one or more axes. The present systems and methods are suitable for use, for example, by unmanned aerial vehicles (UAVs).
1. A method for automatically white balancing a digital image, comprising:
in response to a white balancing trigger, automatically adjusting relative positions of an image sensor and a reference region having a color compatible for white balancing such that the image sensor is positioned to acquire an image of the reference region; and
white balancing the digital image based on the image of the reference region acquired using the image sensor.
2. The method of claim 1 , wherein said automatically adjusting comprises adjusting the relative positions in response to the white balance trigger being a determination that the digital image lacks a region suitable for use as a white balancing reference.
3. The method of claim 1 , wherein said automatically adjusting comprises adjusting the relative positions in response to the white balance trigger comprising a user command.
4. The method of claim 1 , wherein said automatically adjusting comprises automatically moving the image sensor such that the reference region is within the field-of-vision of the image sensor.
5. The method of claim 4 , further comprising recording the position of the reference region prior to said automatically adjusting and moving the image sensor according to the recorded position of the reference region.
6. The method of claim 5 , wherein said automatically adjusting comprises enabling the image sensor to scan surroundings of the image sensor to locate the reference region.
7. The method of claim 6 , wherein said enabling the image sensor includes enabling the image sensor to locate the reference region by recognizing one or more markers on the reference region.
8. The method of claim 1 , wherein said automatically adjusting comprises automatically moving the reference region into the field-of-vision of the image sensor.
9. The method of claim 1 , further comprising automatically restoring the position of at least one of the image sensor and the reference region after acquiring the image of the reference region.
10. An imaging system, comprising:
an image sensor for acquiring a digital image; and
an image processor for white balancing the digital image based on an image of a reference region having a color compatible for white balancing,
wherein the image processor is configured to, in response to a white balancing trigger, automatically adjust the position of the image sensor relative to a position of the reference region such that the image sensor is positioned to acquire the image of the reference region.
11. The imaging system of claim 10 , wherein said image sensor is operatively mounted to a gimbal mechanism for rotating said image sensor about at least one axis.
12. The imaging system of claim 10 , wherein the white balance trigger comprises a determination by the image processor that a digital image of interest lacks a region suitable for use as a white balancing reference.
13. The imaging system of claim 10 , wherein the white balance trigger comprises a user command.
14. The imaging system of claim 10 , wherein said image processor is configured to move said image sensor such that the reference region is within a field-of-vision of said image sensor.
15. The imaging system of claim 14 , wherein said image processor is configured to direct said image sensor to scan its surroundings to locate the reference region.
16. The imaging system of claim 15 , wherein the image sensor is configured to locate the reference region by recognizing one or more markers of the reference region.
17. The imaging system of claim 10 , wherein said image processor is configured to move the reference region into a field-of-vision of the image sensor.
18. The imaging system of claim 10 , wherein the image processor is configured to automatically restore the position of at least one of the image sensor and the reference region.
19. An apparatus, comprising:
a mechanism for automatically adjusting, in response to a white balancing trigger, a position of an image sensor relative to a position of a reference region having a color compatible for white balancing such that the image sensor is positioned to acquire an image of the reference region.
20. The apparatus of claim 19 , wherein said mechanism comprises a gimbal mechanism.