1. A digital image signal processing method comprising: determining a saturation condition by comparing a delta between a plurality of pieces of image data of an input image exhibiting different color components with a standard for white scene recognition, wherein the determining of the saturation condition comprises: determining a maximum value from among a plurality of pieces of image data exhibiting different color components on a selected region; determining a minimum value from among the plurality of pieces of the image data of the selected region; calculating a delta between the maximum value and the minimum value; comparing the delta to a first standard; and determining that the selected region satisfies a saturation condition of a white mode when the delta is less than a first standard; determining a brightness condition by using a distribution of grey levels of the input image; and determining that the input image is a white scene when the input image satisfies the saturation condition and the brightness condition.