The present invention relates to an apparatus and method for normalization of an image signal, particularly for use in perceptual video and still image quality measurement when the quality measurement is achieved by making a comparison between a reference signal and a decoded signal. During the premixing or the extruding zeolites are added having pores of a size larger than 2. The processing device rejects the fault detection signals when they fail to meet a selected condition and the contacts are closed, and declares end of life when the selected condition is met.