“…The potential applications of two-dimensional (2-D) discrete systems in image data processing, seismographic data processing, thermal processes, gas absorption, water stream heating, and so forth, (Bose, 1982; Bracewell, 1995; Kazorek, 1985; Lu and Antoniou, 1992) have received considerable attention in recent years. The stability properties of 2-D discrete systems described by the Roesser model (Roesser, 1975) have been investigated extensively (Agathoklis et al, 1989; Anderson et al, 1986; Bauer and Jury, 1990; Bauer and Ralev, 1998; El-Agizi and Fahmy, 1979; Kar, 2008a, 2008b; Kar and Singh, 1997, 2000, 2001, 2005; Leclerc and Bauer, 1994; Liu and Michel, 1994; Lodge and Fahmy, 1981; Singh, 2007; Tzafestas et al, 1992; Xiao and Hill, 1996, 1999). The stability margin of 2-D discrete systems has been studied in Agathoklis (1988), Agathoklis et al (1982) and Swamy et al (1981).…”