Automatic white balance detection and correction of an image captured in a digital camera

Claim 1

A digital camera, comprising: a lens; a plurality of color filters adjacent the lens; an array of detectors for each receiving through the lens and a corresponding one of the color filters light reflected from a scene and outputting a signal representative of an amount of light detected; circuit means connected to the array for processing the signals from the detectors and generating a set of digital image data including a red-green-blue (rgb) value for each of a plurality of pixels representing an uncorrected image of the scene; and control means for mapping a two-dimensional gamut representation of the digital image data into a two-dimensional gamut representation of a set of reference image data and adjusting selected ones of the values of the set of digital image data in accordance with a predetermined transform to white balance the uncorrected image of the scene and produce a modified set of digital image data representing a corrected image of the scene, the control means performing the two-dimensional mapping by reducing each of the rgb values in the digital image data to a red/blue value and a green/blue value and generating the two-dimensional gamut representing a map of the red/blue and green/blue values for each pixel in the digital image data, generating a set of two-dimensional shapes through plotting the transforms that map each of a plurality of peripheral points of the two-dimensional gamut into a plurality of peripheral reference image gamut points, and then adjusting the selected ones of the values of the set of digital image data based on the intersection of the set of two-dimensional shapes to white balance the uncorrected image of the scene and produce a modified set of digital image data representing a corrected image of the scene.

Claim 8

A method of white balance detection and correction of an image captured in a digital camera, comprising the steps of: generating a set of digital image data including a red-green-blue (rgb) value for each of a plurality of pixels representing an uncorrected image of the scene; and mapping a two-dimensional gamut representation of the digital image data into a two-dimensional gamut representation of a set of reference image data and adjusting selected ones of the values of the set of digital image data in accordance with a predetermined transform to white balance the uncorrected image of the scene and produce a modified set of digital image data representing a corrected image of the scene, the two-dimensional mapping being performed by reducing each of the rgb values in the digital image data to a red/blue value and a green/blue value, and generating the two-dimensional gamut representing a map of the red/blue and green/blue values for each pixel in the digital image data, generating a set of two-dimensional shapes through plotting the transforms that map each of a plurality of peripheral points of the two-dimensional gamut into a plurality of peripheral reference image gamut points, and then adjusting the selected ones of the values of the set of digital image data based on the intersection of the set of two-dimensional shapes to white balance the uncorrected image of the scene and produce a modified set of digital image data representing a corrected image of the scene.

Claim 9

A method of white balance detection and correction of an image captured in a digital camera, comprising the steps of: generating a set of digital image data including a red-green-blue (rgb) value for each of a plurality of pixels representing an uncorrected image of the scene; and mapping a two-dimensional gamut representation of the digital image data into a two-dimensional gamut representation of a set of reference image data and adjusting selected ones of the values of the set of digital image data in accordance with a predetermined transform to white balance the uncorrected image of the scene and produce a modified set of digital image data representing a corrected image of the scene, the two-dimensional mapping being performed by reducing each of the rgb values in the digital image data to a red/blue value and a green/blue value, and generating the two-dimensional gamut representing a map of the red/blue and green/blue values for each pixel in the digital image data, generating a set of two-dimensional shapes through plotting the transforms that map each of a plurality of peripheral points of the two-dimensional gamut into a plurality of peripheral reference image gamut points, and then adjusting the selected ones of the values of the set of digital image data based on the intersection of the set of two-dimensional shapes to white balance the uncorrected image of the scene and produce a modified set of digital image data representing a corrected image of the scene.