This document summarizes an extended matrix encoding algorithm for steganography proposed in a research paper. The algorithm aims to improve the embedding efficiency and rate of the classic F5 steganography system. It does this by extending the hash function used in matrix encoding to multiple layers, allowing more secret bits to be embedded into each carrier cell while still only modifying one bit. The encoding is represented by a quad (dmax, n, k, L) where L indicates the maximum extension layer. Secret bits are tested against specific extended codes up to layer L, and if they match, additional bits can be embedded into the carrier cell. Experimental results showed the extended algorithm performs better than the classic F5 system.