1. An imaging device, comprising: a pixel array for capturing an image; and an image processing circuit for performing a white balancing operation; the image processing circuit comprising: a first circuit portion for: calculating first respective distances between a node from a selected pixel from the captured image and each node on a white curve defining a predetermined white area of the image sensor, where the nodes are plotted in a two-dimension space; selecting two of the white curve nodes closest to the selected pixel node; dividing an interval between the two closest white curve nodes into multiple intervals having a set of sub-nodes; calculating second respective distances between the selected pixel node and each sub-node; selecting a distance determined to be shortest distance among the second respective distances; and saving pixel data for a selected pixel if said selected distance is less than a predetermined value; and a second circuit portion for performing an automatic white balance operation using the saved pixel data.