A system and method for facsimile data encoding uses vectors indicating the locations of changing elements along a horizontal scan line. The change vectors are stored in a vector table. The system may use a reference vector table and a coding vector table if CCITT recommendation T.6 two dimensional encoding is used. The system encodes horizontal scan lines using the vectors to determine the location of the changing elements. The value of the reference changing element is easily determined using the vector tables. The system determines the locations of all changing elements on a horizontal scan line before performing any encoding of that particular scan line thus simplifying the encoding process. The system can receive and decode facsimile data to generate change vectors. The change vectors provide a simple mechanism for regenerating the raw data. The change vectors are used to encode raw data into any standard facsimile encoding format, to decode facsimile data, and to interconvert from one encoding format to another without having to convert the encoded data back to raw data.