1. A display driver for driving a display panel, the display driver comprising: a correction parameter register which stores a correction parameter for correcting a contrast adjustment value that is instructed by a processing section; a computation circuit which adds a correction value specified by the correction parameter to the contrast adjustment value instructed by the processing section, and calculates a corrected contrast adjustment value; and a drive circuit which drives a display panel at a drive voltage that is obtained based on the computed corrected contrast adjustment value.