Image processing is discussed for RAW format in digital cameras. The points are (1) suppression of noises, (2) amplifier of colors, (3) projection of dynamic range. Base technique is Fourier transformation in finite period. The expression is known as for multi-dimensional forms. However, if it is applied simply for image photographed in fields, he/she would get less information than his/her expectation. The reason is to make inappropriate preprocessing for Fourier transformation. We propose preprocessing about (1~3) points; and as several typical cases, we show the effects.\n Figures and graphs are drawn by using full color. The true images will be got from Web-pages.