An integrated-circuit image sensor that includes an array of pixel regions composed of binary pixel circuits. Each binary pixel circuit includes a binary amplifier having an input and an output. The binary amplifier generates a binary signal at the output in response to whether an input voltage at the input exceeds a switching threshold voltage level of the binary amplifier. A light-detecting element of the binary pixel circuit is coupled to the input of the binary amplifier. Initialization circuitry of the binary pixel circuit is coupled to the input of the binary amplifier. The initialization circuitry sets the input voltage to a level that is offset relative to the switching threshold voltage level of the binary amplifier by an offset voltage amount, the offset voltage amount representing a threshold amount of light incident on the light detecting element.