Figure 4.

The PBS model. Encoding phase: The image (here, the match), is encoded in terms of pixel values contained in vector m. Template response: m is correlated with a similar representation, t, of the target image. The result is rectified, passed through a power function, and corrupted by additive noise, N_c, yielding noisy scalar response value, . Decision phase: The observer derives a similar response to the distractor, , and compares it to . The stimulus yielding the maximum response is the observer's choice for the match stimulus.