1. A method of performing a color balancing operation on input image data from an image sensor, said input image data having a plurality of color channels, said method comprising: using a processing circuit to perform the acts of: determining a first chromaticity value for each color channel of the input image data by dividing a sum chromaticity value for each color channel of a plurality of pixels by a sum chromaticity value for all color channels of said plurality of pixels; and calculating color channel gains for each respective color channel of the input image data by dividing the respective first chromaticity values of all color channels of said plurality of color channels other than said respective color channel by a sum of second chromaticity values of corresponding color channels of a neutral white point; and transforming the input image data to an output image by applying the color channel gains to respective said color channels of said input image data.