Facsimile coding using symbol-matching techniques

In this paper, a symbol-matching technique for digital facsimile transmission is described. This technique results in data compression factors typically 2.5 to 3 times that obtained by the standard CCITT codes. New signal-modification techniques are also described. These distort the picture to be transmitted at a microscopic level to increase the correlation between pels. However, the resulting gains in data compression were found to be small.