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.
The G3 format is used to compress image files in TIFF format when sending faxes. The compression algorithm allows for the use of a standard 10-times compression, which can be increased. It is used to remove excess image data, which makes it possible to reduce the size of the image and speed up delivery.