You can compress and decompress gray scale, palette, and bitonal images using Packbits, a lossless method. Packbits is fast, widely-supported, and provides good compression of sparse images, such as scanned documents.
While providing less compression than LZW, Packbits-compressed files are more common than LZW-compressed files on all systems. Therefore, Packbits is a logical compression method for files you may send to various systems. On all systems, LZW-compressed files are the next most common compressed files after Packbits-compressed files.