Aspects of the present invention relate to systems and methods for characterization of background regions of substantially-uniform color in a digital image. According to a first aspect of the present invention, a histogram of the first-channel values of a plurality of image pixels may be formed, and a peak region in the first-channel histogram may be detected. Subsequently a histogram of image values of a second channel may be formed accumulating second-channel values for only those image pixels with first-channel values within the peak region of the first-channel histogram, and a peak region in the second-channel histogram may be detected. An image characteristic may be associated with image pixels with first-channel and second-channel values within the first-channel peak and the second-channel peak regions, respectively.