Conductive additives, the aqueous inks and precoat agent compositions to which the additives are added, and the methods for using such conductive additives in the aqueous inks and precoat agent compositions in printing processes employing microwave or radiofrequency drying processes. A seat portion base body is provided in a housing provided with a valve passage and allows a piston for opening and closing a valve passage to be pressed on the seat portion base body. A separating device is arranged above the low-pressure chamber. The method includes, for each pixel in the third plurality of pixels, normalizing the pixel’s value as a function of the pixel values of at least six other pixels in the third plurality of pixels. Intra compression, inter compression with motion detection, and inter compression with motion estimation are performed on a block by block basis, as needed.