1. Spectacles for use in viewing images or videos, comprising: (a) at least two lenses each having an adjustable optical property; (b) an image capture device associated with the spectacles for receiving a digital image comprising a plurality of digital image channels each containing multiple pixels; (c) the image capture device capturing a digital image; (d) a processor for computing a feature vector from pixel values of the digital image channels wherein the feature vector includes a feature value that is a function of a coincidence factor between edge locations in two or more digital image channels and the feature value indicates whether the digital image is an anaglyph or a non-anaglyph image; (e) the processor producing an anaglyph classification by analyzing the digital image to classify the digital image as either an anaglyph or as a non-anaglyph based on the feature vector; and (f) the processor controlling an optical property of at least one of the two lenses based on the anaglyph classification.