1. A system for reconstructing an input signal comprising: a first differentiator configured to receive the input signal and generate a first signal representing the first derivative of the input signal; a second differentiator configured to receive the first signal and generate a second signal representing the second derivative of the input signal; a controller configured to receive the second signal and generate a quantization step; a level-crossing sampling block configured to receive the first signal and the quantization step and generate level-crossed samples of the first signal; a zero-order holding block configured to receive the level-crossed samples and the quantization step and generate a quantized signal; and an integrator configured to receive the quantized signal and the quantization step and generate a third signal representing a reconstructed signal of the input signal.