An information-spectrum approach to source coding theorems with a fidelity criterion

The general rate-distortion problem for the general class of nonstationary and/or nonergodic sources with an arbitrary distortion measure (not necessarily additive) is studied. We are especially concerned with the case of variable-rate coding under maximum-distortion criterion. It turns out that, in the framework where we can not invoke the standard asymptotic equipartition property, an information spectrum approach plays the key role in establishing such a general formula