In this paper we analyze the performance of the nonlinear joint transform correlator in terms of output signal to noise ratio. The main assumption used is that the signal energy is small relative to that of the additive noise; this assumption is defensible in practice due to the generally small spatial extent of target images relative to scenes. This work is an extension of that in an earlier paper. The previous analysis was carried out under a restriction that the signal and noise spectra were similar (actually multiples of one another). In the current work there is no such constraint. Further, the current work assumes sampled data; this is mostly for the sake of variety, and serves as a complement to the spatially continuous formulation of the earlier paper.