An exemplary illumination normalization method is provided which includes receiving an input image having at least one spurious edge directly resulting from illumination, performing anisotropic diffusion on the input image to form a diffusion image, and removing at the least one spurious edge using the diffusion image. Responsibility for executing these operations can be distributed among different sets of computation units. The accommodating member includes a recording medium holding portion for positioning and holding the recording medium to be held in the first accommodating region and a recording device holding portion for positioning and holding the recording device to be held in the second accommodating region. The transaction processing resources are then monitored to count the number of transactions processed, measure the processing time for individual transactions, and capture their corresponding transaction result code. An adjustment quantity calculation portion calculates an adjustment quantity representing a degree of decrease of a slew rate of the specific signal, based on the adjustment coefficient, the specific signal and the two adjacent signals. A switching unit includes a control input, and configured to activate andor to deactivate the AC unit dependent on a signal applied to the control input.