This bitmap format is used in the Kodak DC series family of cameras. It is also known under the name Kodak Photogen. KDC is a RAW photo format for the post-processing of photos that has the ability to change key image parameters while maintaining the original level of detail.
Format for representing colors in the three primary colors (red, green and blue), each of which has 255 gradations. In contrast to the standard RGB, it allows you to change the transparency of the entire image using the opacity parameter. It is less flexible in terms of transparency settings than RGBA.