A system extracts effective parameters from a pixel circuit that includes a light emitting device, a drive device to provide a programmable drive current to the light emitting device, a programming input, and a storage device to store a programming signal. The system measures the value of at least one operating parameter of the pixel circuit at a plurality of levels, and then extracts the value of at least one related parameter of the pixel circuit, based on the measured values of the at least one operating parameter. The measured values of the operating parameter are translated to effective values for driving the pixel circuit, based on the extracted value. Then effective parameters for driving effective devices in the pixel circuit are extracted, based on the translated values, and stored for use in compensating input signals to the pixel circuit.