An imaging device of the present invention, using image data that has been continuously read out at specified time intervals from an image sensor, generates relatively dark combination image data resulting from relatively dark combination using darker pixel data of each pixel of image data is generated, and relatively bright combination image data resulting from relatively bright combination using brighter pixel data of each pixel of image data, and difference output image data is generated from the relatively bright combination image data and the relatively dark combination image data. With the generated relatively dark combination image data as background image data and the difference output image data as light trace output image data, respective brightness is adjusted, and by subjecting each of the image data after adjustment to addition combination, it is possible to respectively independently adjust background brightness and light trace brightness.