JPS5651159A - Coding method of picture information - Google Patents

Abstract

PURPOSE:To collect continuous parts to code the number of respective picture elements (run length) in respect to parts, where white and black regions are continuous and code half-tone parts, where white or black are transferred to black or white gradually, by the picture element unit. CONSTITUTION:Picture signal (a) is subjected to the processing, where maximum and minimum signals of picture signal (a) are substituted with maximum and minimum signals respectively, and is converted to signal (b). A white picture element is added to the beginning of the read picture signal string to consider coding. White run length is coded collectively. When the picture signal string is changed from the region of white picture elements to the region of half-tone or black picture elements, ''0'' is given when the first picture element is half-tone, and ''1'' is given when the first picture element is black. In the region of continuous black picture elements, black run length is coded collectively. If the picture element is half-tone and picture elements following it are in the half-tone region, code ''0'' is given to every one picture element.