An electronic camera includes a pre-processing block. The pre-processing block fetches four partial images outputted in a parallel manner from an image sensor in response to a clock CLK1 having a frequency equal to or less than 432 MHz, and performs four pre-processes that have responded to a clock CLK2 having a frequency ¼ the frequency of the clock CLK1, on each of the fetched four partial images. An image based on the processed four partial images is outputted from an LCD monitor. An evaluation-image producing circuit responds to a clock CLK3 so as to create an evaluation image based on the processed four partial images. A frequency of the clock CLK3 is adjusted in a range in which ¼ of 432 MHz is the upper limit. A parameter for regulating a quality of an output image is adjusted based on the evaluation image thus created.