14. A display system comprising:a video transmission part configured to output a video signal;
a signal detector configured to detect gradation pixel data included in the video signal input to a display having a plurality of pixels;
a current detector configured to detect a current supplied to part of pixels among the plurality of pixels; and
an output part configured to output current data corresponding to the current supplied to the part of pixels and signal data corresponding to the gradation pixel data used for the part of pixels,
wherein the signal data comprises addition data produced by adding the gradation pixel data and the gradation pixel data being delayed by one frame.